{"gene":"PRMT5","run_date":"2026-06-10T06:43:35","timeline":{"discoveries":[{"year":1999,"finding":"Human PRMT5 (JBP1/SKB1Hs) is a protein methyltransferase that can be cross-linked to radiolabeled S-adenosylmethionine (AdoMet) and methylates histones H2A and H4 as well as myelin basic protein in vitro. Conserved motifs implicated in AdoMet binding are required for activity, as substitution mutants in this region show little or no methyltransferase activity. PRMT5 co-immunoprecipitates with Jak2 and several other proteins that serve as methyl-group acceptors.","method":"AdoMet cross-linking, in vitro methyltransferase assay, active-site mutagenesis, co-immunoprecipitation, yeast two-hybrid","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro enzymatic assay with radiolabeled cofactor, active-site mutagenesis, and protein interaction confirmed by co-IP, founding paper","pmids":["10531356"],"is_preprint":false},{"year":1998,"finding":"The human homolog SKB1Hs can functionally replace fission yeast Skb1 in S. pombe, indicating evolutionary conservation of function. Fission yeast Skb1 negatively regulates mitosis by a mechanism independent of Cdc25 but at least partially dependent on Shk1 and Wee1; Skb1 and Shk1 biochemically associate with Cdc2 in S. pombe, suggesting inhibition of mitosis through interaction with the Cdc2 complex.","method":"Genetic complementation, genetic epistasis, biochemical co-immunoprecipitation with Cdc2","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis combined with biochemical co-IP in yeast model, functional conservation shown by complementation","pmids":["9843966"],"is_preprint":false},{"year":1996,"finding":"Fission yeast Skb1 (ortholog of human PRMT5) interacts with Shk1 (PAK homolog) via the N-terminal regulatory domain of Shk1 at a site distinct from the Cdc42-binding region; Skb1, Shk1 and Cdc42 can form a ternary complex in vivo. Skb1 positively modulates Shk1 function and acts as a component of the morphology-control branch of the Ras signaling cascade.","method":"Yeast two-hybrid, in vivo co-immunoprecipitation (ternary complex), genetic epistasis","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — two-hybrid plus in vivo complex formation and genetic epistasis, yeast ortholog","pmids":["8943016"],"is_preprint":false},{"year":2001,"finding":"Fission yeast Skb1 localizes to cell ends, sites of septation, and nuclei; hyperosmotic shock causes delocalization from cell ends and nuclei and stimulates Skb1 protein methyltransferase activity. The methyltransferase activity of the human homolog Skb1Hs is similarly stimulated by hyperosmotic stress in fission yeast, indicating evolutionary conservation of the stress-responsive activity regulation.","method":"Subcellular localization by fluorescence microscopy, in vitro methyltransferase activity assay under osmotic stress, functional complementation in yeast","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization imaging combined with enzymatic activity measurement under defined stress conditions, conservation confirmed with human protein","pmids":["11278267"],"is_preprint":false},{"year":2016,"finding":"Loss of MTAP leads to intracellular accumulation of methylthioadenosine (MTA), which specifically and potently inhibits PRMT5 enzymatic activity. MTAP-null cells therefore display a hypomorphic PRMT5 state and selective dependence on PRMT5 and its binding partner WDR77. Reconstitution of MTAP in MTAP-deficient cells rescues PRMT5 dependence.","method":"Metabolomic profiling, biochemical methyltransferase inhibition assays (MTA vs. PRMT5), shRNA screening across 390 cancer cell lines, isogenic cell line rescue experiments","journal":"Science (New York, N.Y.)","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — biochemical enzymatic inhibition assay combined with metabolomics and genetic rescue, independently replicated in two concurrent Science papers (PMIDs 26912360 and 26912361)","pmids":["26912360","26912361","27068473"],"is_preprint":false},{"year":2016,"finding":"MTA is a potent and selective inhibitor of PRMT5 among a panel of methyltransferases. MAT2A, which produces the PRMT5 substrate SAM, is also a synthetic lethal target in MTAP-deleted cells because MAT2A depletion reduces SAM levels and further attenuates PRMT5 methylation activity. RIOK1, a PRMT5 co-complex protein, is also a vulnerability in MTAP-deleted cells.","method":"Biochemical methyltransferase enzyme panel profiling, metabolomic studies, shRNA screening, co-complex identification","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — enzyme panel biochemical profiling plus metabolomics and genetic depletion, replicated across multiple laboratories","pmids":["27068473"],"is_preprint":false},{"year":2017,"finding":"The PRMT5:MEP50 complex forms a 453 kDa heterooctamer. Crystal structures of this complex bound to an S-adenosylmethionine analog and a substrate peptide reveal the mechanism of substrate recognition and procession to dimethylation.","method":"Crystal structure determination of human PRMT5:MEP50 complex with SAM analog and substrate peptide","journal":"Sub-cellular biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structure of the complex with cofactor and substrate, provides atomic-level mechanistic insight","pmids":["28271477"],"is_preprint":false},{"year":2018,"finding":"LKB1 directly interacts with and phosphorylates PRMT5 at T132, T139 and T144 residues in its TIM-barrel domain. Point mutations T139A/T144A drastically reduce PRMT5 methyltransferase activity, likely by disrupting interaction with regulatory cofactors MEP50, pICln and RiOK1. Modulation of LKB1 expression alters PRMT5 activity.","method":"Co-immunoprecipitation, in vitro kinase assay identifying phosphorylation sites, point mutagenesis of PRMT5, methyltransferase activity assay","journal":"International journal of cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal co-IP, site-directed mutagenesis, and activity assays in single laboratory","pmids":["30289978"],"is_preprint":false},{"year":2019,"finding":"PRMT5 functions in complex with MEP50/WDR77 and is responsible for the vast majority of symmetric dimethylarginine in cells. A CRISPR/Cas9 screen identified PRMT5, MEP50/WDR77, PPP4C, SMNDC1, and SRSF3 as components of the PRMT5 writer/reader pathway. Loss of PRMT1 (the major asymmetric arginine methyltransferase) also sensitizes cells to PRMT5 inhibition, demonstrating partial redundancy between the PRMT5 and PRMT1 pathways.","method":"CRISPR/Cas9 genetic screen, combinatorial inhibitor treatment, genetic epistasis","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genome-wide CRISPR screen with functional follow-up, single lab but multiple cell models","pmids":["30916320"],"is_preprint":false},{"year":2020,"finding":"PRMT5 is phosphorylated at residue Y324 by Src kinase, which suppresses PRMT5 activity by preventing its binding to the methyl donor S-adenosyl-L-methionine. PRMT5 activity promotes non-homologous end joining (NHEJ) DNA repair by methylating and stabilizing 53BP1; Src-mediated phosphorylation of PRMT5 during DNA damage inhibits NHEJ and promotes apoptosis.","method":"Site-specific phosphorylation assay, mutagenesis of Y324, SAM-binding assay, co-immunoprecipitation of PRMT5 with 53BP1, NHEJ repair assays, cell survival after DNA damage","journal":"Communications biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis of phosphorylation site with functional methyltransferase and DNA repair readouts, single lab","pmids":["32759981"],"is_preprint":false},{"year":2020,"finding":"PRMT5 methylation of IFI16/IFI204 (components of the cGAS/STING pathway) attenuates cytosolic DNA-induced IFN and chemokine expression in melanoma cells. PRMT5 also inhibits NLRC5 transcription, reducing MHC class I antigen presentation. PRMT5 knockdown augments IFN and chemokine production and increases MHC class I abundance.","method":"PRMT5 knockdown (shRNA), pharmacological inhibition (GSK3326595), measurement of IFN/chemokine production, NLRC5 and MHCI expression, immunocompetent vs immunocompromised mouse models","journal":"Science translational medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic and pharmacological inhibition with multiple pathway readouts, in vivo validation, single lab","pmids":["32641491"],"is_preprint":false},{"year":2021,"finding":"PRMT5 promotes AKT1 activation by catalyzing symmetric dimethylation of AKT1 at arginine 391 (R391). R391 methylation cooperates with PIP3 to relieve the PH-in conformation of AKT1, enabling its translocation to the plasma membrane and subsequent activation by PDK1 and mTORC2. Deficiency in AKT1-R391 methylation significantly suppresses AKT1 kinase activity and tumorigenesis.","method":"In vitro methylation assay, mutagenesis of AKT1-R391, AKT1 membrane translocation assay, kinase activity assay, co-immunoprecipitation with PDK1/mTORC2, xenograft tumor models","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vitro methylation assay plus mutagenesis plus membrane translocation and kinase activity assays, corroborated by two independent papers (PMIDs 34103528 and 35803962)","pmids":["34103528","35803962"],"is_preprint":false},{"year":2021,"finding":"PRMT5 uses modular adaptor proteins (CLNS1A/pICln, RIOK1, and COPR5) for substrate recruitment through an evolutionarily conserved peptide motif shared among all three adaptors. This motif is necessary and sufficient for interaction with PRMT5. Disruption of the PRMT5-adaptor interface impairs methylation of adaptor-recruited substrates including spliceosome Sm proteins, histones, and ribosomal complexes, affects Sm spliceosome activity leading to intron retention, and impairs growth of MTAP-null tumor cells.","method":"Structural resolution of the PRMT5-adaptor interface, mutagenesis of the binding motif, methylation assays of adaptor-recruited substrates, RNA splicing assays, MTAP-null cell growth assays","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 1 / Strong — structural resolution combined with mutagenesis, substrate methylation assays, and functional splicing readout in one rigorous study","pmids":["34358446"],"is_preprint":false},{"year":2021,"finding":"PRMT5 regulates the expression of the E3 ubiquitin ligase RNF168, thereby stabilizing H2AX. Suppression of PRMT5 (e.g., in MTAP-deficient cells) reduces RNF168 expression, leading to destabilization of H2AX by E3 ubiquitin ligase SMURF2, resulting in higher levels of spontaneous and genotoxic-agent-induced DNA damage.","method":"shRNA knockdown of PRMT5/RNF168/SMURF2, co-immunoprecipitation to show RNF168 and SMURF2 interactions with H2AX, H2AX stability assays, DNA damage measurement in MTAP-deficient glioblastoma cells","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic knockdown cascade with co-IP for protein interactions, single lab with multiple orthogonal methods","pmids":["31533041"],"is_preprint":false},{"year":2021,"finding":"MAT2A inhibition reduces SAM levels, which attenuates PRMT5 activity, causing widespread splicing perturbations (particularly of cell cycle genes) and subsequent DNA damage and mitotic defects in MTAP-null cells.","method":"Potent MAT2A inhibitor characterization, RNA sequencing, proteomics, measurement of SAM levels, DNA damage and mitotic defect assays in HCT116 MTAP-/- cells","journal":"Cancer cell","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — biochemical inhibitor with mechanistic profiling by RNA-seq, proteomics, and functional assays, rigorous study","pmids":["33450196"],"is_preprint":false},{"year":2021,"finding":"PRMT5 inhibition causes widespread disruption of mRNA splicing across the transcriptome in glioblastoma, particularly affecting cell cycle gene products, consistent with its role in methylating spliceosome components.","method":"Pharmacological inhibition with two orthogonal PRMT5 inhibitors (GSK591 and LLY-283), RNA sequencing of 46 patient-derived GBM stem cell cultures, in vivo brain-penetrant inhibitor study","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — two orthogonal inhibitors, large patient-derived cohort, RNA-seq mechanistic readout, in vivo validation","pmids":["33579912"],"is_preprint":false},{"year":2021,"finding":"PRMT5 inhibition in GBM neurospheres causes G1 cell cycle arrest through upregulation of p27 and hypophosphorylation of retinoblastoma protein, leading to senescence. Chromatin immunoprecipitation revealed that PRMT5 regulates PTEN expression in GBM neurospheres via methylation, controlling Akt and ERK activity; PTEN is identified as a downstream target of PRMT5 in GBM neurospheres.","method":"shRNA knockdown, Human Phospho-Kinase Array, chromatin immunoprecipitation-PCR for PTEN promoter, cell cycle analysis, in vivo intracranial tumor model","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-PCR plus phospho-kinase array plus in vivo model, single lab","pmids":["27292259"],"is_preprint":false},{"year":2018,"finding":"PRMT5 methylates histone H4R3 (H4R3me2s) to catalyze symmetric methylation critical for oligodendrocyte differentiation and developmental myelination. Decreased H4R3me2s upon PRMT5 loss is followed by increased nuclear H4K5 acetylation; pharmacological inhibition of histone acetyltransferases rescues the differentiation defect, establishing a cross-talk between histone arginine methylation and lysine acetylation.","method":"Pharmacological inhibition, CRISPR/Cas9 knockout, conditional genetic ablation (Prmt5 conditional KO in progenitors), histone modification analysis with purified histones, differentiation/survival assays in oligodendrocyte progenitors and mice","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — multiple genetic and pharmacological approaches with mechanistic histone crosstalk validated in purified histones and in vivo mouse model","pmids":["30026560"],"is_preprint":false},{"year":2021,"finding":"Arginine methyltransferase PRMT5 directly binds cGAS and catalyzes symmetric dimethylation of cGAS at Arg124 (R124). This methylation attenuates cGAS-mediated antiviral immune response by blocking the DNA-binding ability of cGAS.","method":"Co-immunoprecipitation (PRMT5–cGAS interaction), in vitro methylation assay identifying R124, DNA-binding assay showing blockade, in vivo HSV-1 infection model with PRMT5 inhibitors","journal":"Science advances","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP plus methylation site identification plus functional DNA-binding assay, single lab","pmids":["33762328"],"is_preprint":false},{"year":2022,"finding":"PRMT5 inhibition in lung cancer reduces symmetric dimethylation of histone H4R3 (H4R3me2s) at the CD274 (PD-L1) promoter locus, thereby de-repressing CD274 gene expression and increasing PD-L1 on tumor cells, activating the PD1/PD-L1 axis and eliminating CD8+ T cell anti-tumor immunity.","method":"ChIP analysis of H4R3me2s at CD274 promoter, shRNA knockdown, PRMT5 inhibitor treatment, in vitro and in vivo measurement of PD-L1 expression","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP assay demonstrating direct histone mark at CD274 promoter plus functional immune readout, single lab","pmids":["35111150"],"is_preprint":false},{"year":2022,"finding":"PRMT5 methylates KEAP1, downregulating NRF2 and its downstream targets. In TNBC with high ferrous levels, this PRMT5-mediated NRF2 suppression inhibits the HMOX1 pathway and promotes ferroptosis resistance by slowing ferrous import.","method":"Biochemical assays for KEAP1 methylation by PRMT5, co-IP, measurement of NRF2 targets and cellular ferrous levels, ferroptosis assays in TNBC vs non-TNBC cells","journal":"Journal for immunotherapy of cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — methylation and co-IP assays with functional ferroptosis readout, single lab","pmids":["37380368"],"is_preprint":false},{"year":2022,"finding":"PRMT5 promotes ALKBH5 nuclear translocation by methylating ALKBH5 at an arginine residue, enhancing ALKBH5-mediated removal of m6A methylation from BRCA1 mRNA, stabilizing BRCA1 mRNA, increasing DNA repair competency, and decreasing doxorubicin efficacy in breast cancer cells.","method":"PRMT5 inhibition and shRNA knockdown, m6A quantification, ALKBH5 subcellular fractionation/localization, BRCA1 mRNA stability measurement, DNA repair assays","journal":"Molecular therapy : the journal of the American Society of Gene Therapy","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — subcellular fractionation with functional mRNA stability and DNA repair readouts, single lab","pmids":["35278676"],"is_preprint":false},{"year":2022,"finding":"PRMT5 interacts with SMAD4 and methylates it at R361 upon TGF-β1 treatment. R361 methylation is required for SMAD complex formation and nuclear import, driving EMT and colorectal cancer metastasis. SMAD4 R361A mutation abolishes PRMT5/TGF-β1-induced metastasis.","method":"Mass spectrometry identification of R361 methylation, co-immunoprecipitation, immunofluorescence, SMAD complex formation assay, nuclear import assay, EMT and metastasis assays with mutant SMAD4","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — MS-based methylation site ID plus co-IP/IF with mutagenesis functional validation, single lab","pmids":["36991117"],"is_preprint":false},{"year":2021,"finding":"PRMT5 functionally associates with EZH2 (confirmed by co-IP and GST pulldown). PRMT5 deposits H4R3me2s and H3R8me2s marks at the CDKN2B promoter; knockdown reduces these marks and the accompanying CpG methylation, reactivating CDKN2B expression. PRMT5 interaction with EZH2 leads to enhanced EZH2 binding and H3K27me3 at the CDKN2B locus.","method":"Co-immunoprecipitation, GST pulldown, ChIP assay (H4R3me2s, H3R8me2s, H3K27me3 at CDKN2B promoter), bisulfite sequencing, luciferase reporter","journal":"Theranostics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal co-IP and GST pulldown plus ChIP with multiple marks, single lab","pmids":["33664859"],"is_preprint":false},{"year":2019,"finding":"PRMT5 is required for B cell development and antibody responses in mice. PRMT5 prevents p53-dependent blocks at the Pro-B cell stage and p53-independent apoptosis in mature B cells during activation; it promotes germinal center expansion and ensures RNA splicing fidelity in germinal center B cells.","method":"Conditional B cell-specific Prmt5 knockout mice, flow cytometry, RNA-seq (splicing analysis), p53-dependency tested by genetic crosses","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional KO with defined cellular phenotypes at multiple B cell stages, RNA-seq mechanistic readout, rigorous genetic dissection of p53 dependence","pmids":["30604754"],"is_preprint":false},{"year":2019,"finding":"Zebrafish Prmt5 methylates germ cell-specific proteins Zili and Vasa (symmetric dimethylarginine) as well as histones H3R8me2s and H4R3me2s. Loss of Prmt5 reduces methylation of these substrates in gonads, downregulates Piwi pathway proteins, and causes germ cell apoptosis and failure of gonadal differentiation, leading to infertile male phenotype.","method":"Prmt5-null zebrafish model, immunostaining for H3R8me2s and H4R3me2s, western blot for Zili/Vasa methylation, gene expression analysis of meiosis/gonad genes","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo knockout with direct methylation substrate identification and functional phenotype, single lab in zebrafish model","pmids":["31533925"],"is_preprint":false},{"year":2020,"finding":"PRMT5 deletion in T cells reduces expression of the common gamma chain (γc), impairing IL-7-mediated survival and IL-2-mediated TCR-induced proliferation. PRMT5 is required for NKT cell development and peripheral T cell maintenance, homeostatic survival, and lymphopenic expansion in vivo.","method":"T cell-specific conditional PRMT5 knockout mice, flow cytometry, in vitro cytokine signaling assays, in vivo lymphopenic expansion model","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean conditional KO with defined cellular and signaling phenotypes, single lab","pmids":["32328070"],"is_preprint":false},{"year":2015,"finding":"PRMT5 methylates arginine residues in the third intracellular loop of the human D2 dopamine receptor. Mutation of these arginine residues reduces D2 receptor-mediated inhibition of cAMP signaling in HEK293T cells. In C. elegans, PRMT5 (prmt-5) promotes dopamine-mediated modulation of chemosensory and locomotory behaviors through the DOP-3 receptor.","method":"In vitro methylation assay of D2 receptor peptide by PRMT5, arginine-to-alanine mutagenesis of receptor, cAMP signaling assay in HEK293T cells, behavioral assays in prmt-5 C. elegans mutants","journal":"Science signaling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro methylation assay plus mutagenesis plus functional cAMP and behavioral readouts, two model systems","pmids":["26554819"],"is_preprint":false},{"year":2017,"finding":"Menin and PRMT5 cooperate to suppress GLP1 receptor (GLP1R) transcript levels. In β-cells, PRMT5 (together with menin) suppresses PKA-mediated phosphorylation of FOXO1 and CREB downstream of GLP1 signaling, likely through arginine methyltransferase activity.","method":"Co-immunoprecipitation of menin-PRMT5 complex, gene expression analysis, phosphorylation assays for FOXO1 and CREB, small-molecule menin inhibitor rescue, ex vivo islet assays","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"Low","confidence_rationale":"Tier 3 / Weak — co-IP and expression data with pharmacological manipulation, single lab, limited direct mutagenesis of PRMT5 activity","pmids":["28270438"],"is_preprint":false},{"year":2021,"finding":"PRMT5 inhibition disrupts splicing of the ATF4 transcript, producing intron-retaining ATF4 mRNA that is detained in the nucleus, reducing cytoplasmic spliced ATF4 protein, downregulating ATF4 target genes, increasing oxidative stress, and inducing cellular senescence in AML cells.","method":"RNA sequencing, nuclear/cytoplasmic fractionation of ATF4 mRNA, ROS measurement, senescence assays, PRMT5 inhibitor treatment","journal":"Redox biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNA-seq with fractionation and functional oxidative stress readouts, single lab","pmids":["35305370"],"is_preprint":false},{"year":2023,"finding":"PRMT5 symmetrically dimethylates MST2 (STK3) at R461 and R467 in its SARAH domain. This methylation suppresses MST2 autophosphorylation and kinase activity by blocking its homodimerization, inactivating the Hippo signaling pathway and promoting pancreatic cancer progression.","method":"In vitro methylation assay identifying R461/R467, co-immunoprecipitation, MST2 autophosphorylation assay, homodimerization assay, PRMT5 inhibitor (GSK3326595) in xenograft models","journal":"The EMBO journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro methylation with site ID plus functional kinase and dimerization assays, in vivo validation, single lab","pmids":["37905571"],"is_preprint":false},{"year":2022,"finding":"PRMT5 promotes symmetric dimethylation of NF-κB p65 at arginine 30 (R30) in vascular smooth muscle cells, leading to upregulation of VCAM-1 expression and macrophage adhesion. TMAO-induced Nox4-mediated ROS production drives PRMT5 expression, establishing a Nox4-PRMT5-VCAM-1 axis in TMAO-induced vascular inflammation.","method":"PRMT5 knockdown, VSMC-specific PRMT5 knockout mice, methylation assay of p65-R30, VCAM-1 expression and macrophage adhesion assays, ROS measurement","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — site-specific methylation identification plus in vivo conditional KO with functional inflammatory readout, single lab","pmids":["35379776"],"is_preprint":false},{"year":2024,"finding":"In cardiac fibroblasts, TGF-β stimulation promotes recruitment of a PRMT5/Smad3 complex to the α-SMA (ACTA2) promoter, increasing PRMT5-mediated H3R2 symmetric dimethylation. This mark is recognized by the WDR5/MLL1 methyltransferase complex, which then increases H3K4 trimethylation, enabling fibrotic gene transcription. Fibroblast-specific PRMT5 deletion reduces pressure overload-induced cardiac fibrosis in mice.","method":"ChIP assay of H3R2me2s at α-SMA promoter, Smad3 knockdown reducing H3R2me2s, co-IP of PRMT5/Smad3 complex, fibroblast-specific conditional KO mice, pressure overload model","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP demonstrating specific histone mark at promoter with Smad3 dependency, co-IP, and in vivo conditional KO with functional cardiac phenotype","pmids":["38503742"],"is_preprint":false},{"year":2023,"finding":"PRMT5 methylates FoxO1 (symmetric dimethylarginine), destabilizing it. PRMT5 knockout in myoblasts increases total FoxO1 protein and promotes its cytoplasmic accumulation, activating autophagy and depleting lipid droplets, impairing muscle regeneration. Systemic autophagy inhibition in Prmt5MKO mice restores lipid droplets and moderately improves muscle regeneration.","method":"Myod1Cre-driven Prmt5 conditional KO mice, FoxO1 methylation and stability assays, subcellular fractionation, autophagy flux assays, lipid droplet quantification, genetic autophagy inhibition rescue","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional KO with methylation substrate identification, subcellular localization, and autophagy rescue, single lab","pmids":["37883229"],"is_preprint":false},{"year":2023,"finding":"PRMT5 methylates SREBP1a at arginine residues, increasing its stability. Skeletal muscle-specific PRMT5 knockout reduces SREBP1a dimethylation and stability, impairing de novo lipogenesis. PRMT5 deletion also de-represses the Pnpla2 (ATGL) promoter via reduced H4R3me2s, elevating ATGL-mediated lipolysis. Double knockout of Pnpla2 and Prmt5 normalizes muscle mass and function.","method":"Skeletal muscle-specific Prmt5 KO mice, SREBP1a methylation and stability assays, ChIP of H4R3me2s at Pnpla2 promoter, double KO genetic rescue","journal":"EMBO reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional KO with substrate methylation and ChIP, genetic rescue experiment, single lab","pmids":["37334900"],"is_preprint":false},{"year":2024,"finding":"TBL2 acts as a scaffolding protein that promotes PRMT5-WDR77 (MEP50) interaction. This enhanced interaction increases PRMT5 methyltransferase activity and AKT phosphorylation, promoting breast cancer cell proliferation.","method":"Proteomic analysis, co-immunoprecipitation of TBL2-PRMT5-WDR77 complex, methyltransferase activity assay, AKT phosphorylation measurement, in vitro and in vivo proliferation assays","journal":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP for ternary complex plus functional methyltransferase and kinase activity assays, single lab","pmids":["39499734"],"is_preprint":false},{"year":2025,"finding":"PRMT5 catalyzes symmetric dimethylation of GPX4 at the conserved R152 residue. This methylation prolongs GPX4 half-life by preventing Cullin1-FBW7 E3 ligase binding to GPX4, thereby blocking ubiquitination-mediated GPX4 degradation and suppressing ferroptosis in cancer cells.","method":"In vitro methylation assay of GPX4-R152 by PRMT5, GPX4 half-life measurement, co-immunoprecipitation of GPX4 with FBW7 (with and without methylation), ubiquitination assay, PRMT5 inhibitor in vivo tumor models","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vitro methylation assay with site mutagenesis, protein stability and ubiquitination assays, co-IP demonstrating E3 ligase displacement, in vivo validation","pmids":["40033101"],"is_preprint":false},{"year":2025,"finding":"PRMT5 directly catalyzes symmetric dimethylation of ALKBH5 at R316 (meR316-ALKBH5), enhancing TRIM28-mediated ALKBH5 ubiquitination and degradation. Reduced ALKBH5 decreases m6A demethylation of the CD276 transcript 3' UTR, increasing CD276 mRNA stability and expression, facilitating colorectal cancer immune evasion by inhibiting cytotoxic T-cell function.","method":"In vitro methylation assay identifying R316, co-IP of ALKBH5 with TRIM28, ubiquitination assay, m6A quantification on CD276 transcript, mRNA stability assay, in vivo and in vitro immune evasion assays","journal":"Research (Washington, D.C.)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — methylation site identification, co-IP, ubiquitination and m6A assays in single lab","pmids":["39781264"],"is_preprint":false},{"year":2021,"finding":"PRMT5 regulates PRMT5-mediated dimethylation of Zili (PIWI protein) and Vasa in zebrafish gonads, controls Piwi pathway protein expression, and thereby governs germ cell development; these represent direct non-histone substrates of PRMT5 in vertebrate germline.","method":"Prmt5-null zebrafish, immunostaining for symmetric arginine dimethylation of Zili/Vasa, gene expression profiling","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo KO with direct substrate methylation measurement in zebrafish ortholog model, single lab","pmids":["31533925"],"is_preprint":false},{"year":2023,"finding":"STC2 interacts with PRMT5 and activates it, leading to increased H4R3me2s. Activated PRMT5 promotes DNA double-strand break repair through both homologous recombination and non-homologous end joining pathways, and participates in SLC7A11-mediated ferroptosis resistance in a PRMT5-dependent manner in esophageal squamous cell carcinoma.","method":"Co-immunoprecipitation of STC2-PRMT5, H4R3me2s western blot, DNA repair pathway assays (HR and NHEJ), SLC7A11 expression assays, in vivo validation","journal":"Redox biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP with functional enzymatic activity and DNA repair readouts, single lab","pmids":["36764215"],"is_preprint":false},{"year":2021,"finding":"PRMT5 inhibition in multiple myeloma de-represses CASP1 expression (negatively correlated with PRMT5 levels), leading to CASP1-dependent pyroptosis. PRMT5 silences CASP1 via its histone methyltransferase activity (H4R3me2s).","method":"PRMT5 knockdown, PRMT5 inhibitor treatment, CASP1 expression measurement, pyroptosis markers (N-GSDMD, IL-1b, IL-18), correlation of PRMT5 and CASP1 expression","journal":"Cell death & disease","confidence":"Low","confidence_rationale":"Tier 3 / Weak — knockdown and inhibitor with pyroptosis markers, but direct ChIP of H4R3me2s at CASP1 promoter not reported in abstract","pmids":["34531375"],"is_preprint":false},{"year":2023,"finding":"PRMT5 methylates KLF5 at arginine 41 (R41) in a methyltransferase-activity-dependent manner. This dimethylation stabilizes KLF5 protein by promoting the Akt/GSK3β signaling axis, reducing its degradation and maintaining lung cancer cell proliferation.","method":"Co-immunoprecipitation (PRMT5-KLF5), in vitro methylation assay (R41 site), protein stability assays, KLF5 downstream target analysis, in vivo xenograft with PRMT5 inhibition","journal":"Journal of cellular and molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP and methylation site identification with protein stability assay, single lab","pmids":["37461162"],"is_preprint":false},{"year":2025,"finding":"MST4 kinase, transactivated by NRF2, phosphorylates PRMT5 at S439 and S463 and promotes PRMT5 interaction with METTL3, stimulating PRMT5's methyltransferase activity. PRMT5 then methylates METTL3 at R36 (METTL3-R36me2); this methylation recruits METTL3 to DNA damage sites, promoting RAD51 recruitment for HR-mediated double-strand break repair and cisplatin resistance in ovarian cancer.","method":"In vitro phosphorylation assay (MST4 on PRMT5), co-IP showing increased PRMT5-METTL3 interaction upon phosphorylation, methylation assay identifying R36, ChIP showing METTL3 recruitment to DSB sites, RAD51 foci assay, xenograft model","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple in vitro biochemical assays with site identification and ChIP functional readout, single lab","pmids":["40158218"],"is_preprint":false},{"year":2023,"finding":"PRMT5-mediated methylation of G3BP2 at R468 (G3BP2-R468me2) enhances G3BP2 binding to the deubiquitinase USP7, promoting deubiquitination and stabilization of G3BP2, which activates ACLY and stimulates de novo lipogenesis and tumorigenesis in head and neck squamous carcinoma.","method":"Co-IP of G3BP2-USP7 interaction with and without PRMT5, methylation assay identifying R468, ubiquitination/deubiquitination assay, ACLY activity assay, lipogenesis measurement","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — methylation site identification, co-IP demonstrating USP7 interaction dependency, deubiquitination and lipogenic functional assays, single lab","pmids":["36878903"],"is_preprint":false},{"year":2023,"finding":"PRMT5 inhibition in breast cancer stem cells disrupts splicing of DNA repair genes involved in Fanconi Anemia and homologous recombination pathways (including ATM, DDX11, EXO1, FAN1, SLX4, ATR, RAD17, RAD51D, RUVBL1), causing nuclear retention of intron-containing transcripts and production of non-canonical isoforms with compromised protein function rather than gene expression repression.","method":"RNA sequencing of PRMT5-inhibited BCSCs vs bulk cells, identification of skipped exon and retained intron events, nuclear vs cytoplasmic fractionation of transcripts, apoptosis assays","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNA-seq with nuclear fractionation mechanistic validation identifying specific splice events, single lab","pmids":["39695328"],"is_preprint":false},{"year":2021,"finding":"PRMT5 promotes vascular morphogenesis in zebrafish through transcriptional control of ETS transcription factors and adhesion proteins in endothelial cells. Using a catalytic dead PRMT5 mutant, it was demonstrated that methyltransferase activity is dispensable for vessel formation but required for blood cell formation; PRMT5 acts as a scaffold protein facilitating chromatin looping to regulate transcription during vascular morphogenesis.","method":"Zebrafish prmt5 loss-of-function, catalytic dead PRMT5 mutant rescue experiments, pharmacological methyltransferase inhibition, chromatin conformation assays (reporter gene analysis), ChIP","journal":"PLoS genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — catalytic dead mutant compared to inhibitor clearly separates scaffolding vs enzymatic function, ChIP and chromatin architecture analysis, single lab in zebrafish model","pmids":["34153034"],"is_preprint":false},{"year":2023,"finding":"PRMT5 catalyzes symmetric dimethylation of PRMT5 at CAMK2N1's promoter via H4R3me2s and H3R8me2s marks, repressing CAMK2N1 transcription in prostate cancer cells. This silencing promotes prostate cancer progression in vitro and in vivo.","method":"ChIP assay of H4R3me2s and H3R8me2s at CAMK2N1 promoter, shRNA knockdown and rescue, PRMT5 inhibitor, in vivo tumor growth assays","journal":"Molecular cancer","confidence":"Low","confidence_rationale":"Tier 3 / Weak — ChIP assay showing histone marks at promoter, but this paper is primarily about the circRNA axis; the PRMT5-specific mechanism is adequately supported but secondarily reported","pmids":["35624451"],"is_preprint":false},{"year":2023,"finding":"PRMT5 methylates ULK1 at R532 (monomethylation), suppressing ULK1 activation and attenuating autophagy. Loss or inhibition of PRMT5 removes this methylation, activating ULK1 and triggering cytoprotective autophagy. ULK1 inhibition blocks PRMT5-deficiency-induced autophagy and sensitizes cells to PRMT5 inhibitor.","method":"In vitro methylation assay (ULK1 R532), ULK1 activity assay, autophagy flux assays, ULK1 inhibitor and genetic ablation epistasis experiments, PRMT5 inhibitor sensitivity assays","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro methylation site identification plus functional kinase and autophagy assays with genetic epistasis, single lab","pmids":["37400460"],"is_preprint":false},{"year":2023,"finding":"Alpha-synuclein overexpression enhances BAF complex interaction with PRMT5, globally increasing H4R3me2s symmetric dimethylation. This results in H4R3me2s accumulation near the NRCAM transcription start site and negative regulation of NRCAM, a neuronal differentiation gene. ChIP-seq confirmed H4R3me2s accumulation at the NRCAM locus.","method":"Mass spectrometry interactome of nuclear alpha-synuclein (identifying BAF-PRMT5 interaction), ChIP-seq for H4R3me2s, transcriptomic analysis of NRCAM","journal":"The FEBS journal","confidence":"Low","confidence_rationale":"Tier 3 / Weak — interactome by MS and ChIP-seq, but PRMT5's enzymatic activity specifically driving the H4R3me2s change is inferred from the interaction rather than directly confirmed by PRMT5 mutagenesis","pmids":["38105619"],"is_preprint":false}],"current_model":"PRMT5 is the principal type II protein arginine methyltransferase that, in obligate complex with MEP50/WDR77, catalyzes mono- and symmetric dimethylation of arginine on a broad set of histone (H2A, H4R3, H3R8) and non-histone substrates (AKT1-R391, GPX4-R152, SMAD4-R361, MST2-R461/467, cGAS-R124, ALKBH5-R316, ULK1-R532, 53BP1, KLF5-R41, FoxO1, D2 receptor, and others); substrate recruitment is mediated by adaptor proteins (pICln/CLNS1A, RIOK1, COPR5) sharing a conserved PRMT5-binding motif, and PRMT5 activity is regulated by phosphorylation (Src at Y324 inhibits; LKB1 at T132/T139/T144 modulates cofactor binding; MST4 at S439/S463 activates), by the metabolite MTA (which competitively inhibits PRMT5 when MTAP is deleted), and by scaffolding partners such as TBL2; through these activities PRMT5 controls RNA splicing fidelity, cell cycle progression, DNA damage repair (NHEJ and HR), ferroptosis resistance, AKT-driven oncogenic signaling, innate immune sensing (cGAS/STING), antigen presentation, autophagy, and developmental programs including myelination, B cell development, germ cell specification, and myogenesis."},"narrative":{"mechanistic_narrative":"PRMT5 is the principal type II protein arginine methyltransferase that catalyzes mono- and symmetric dimethylation of arginine on histone and non-histone substrates, governing chromatin states, RNA splicing fidelity, cell cycle, DNA repair, and developmental programs [PMID:10531356, PMID:28271477]. It acts only in obligate complex with MEP50/WDR77, forming a 453 kDa heterooctamer whose crystal structure defines how cofactor binding and substrate peptide engagement drive processive dimethylation [PMID:28271477], and its activity is augmented by scaffolds such as TBL2 that promote the PRMT5-WDR77 interaction [PMID:39499734]. Substrate selection is conferred by a family of modular adaptors (CLNS1A/pICln, RIOK1, COPR5) that dock onto PRMT5 through a single conserved peptide motif necessary and sufficient for binding, directing methylation to spliceosomal Sm proteins, histones, and ribosomal complexes [PMID:34358446]. On chromatin, PRMT5 deposits symmetric H4R3me2s and H3R8me2s marks—and, with Smad3, H3R2me2s—to repress or activate loci including CDKN2B, CD274/PD-L1, the alpha-SMA promoter, and oligodendrocyte differentiation genes, frequently in cooperation with EZH2 or the WDR5/MLL1 complex [PMID:30026560, PMID:35111150, PMID:33664859, PMID:38503742]. As a writer for the spliceosome it safeguards splicing fidelity, and its inhibition produces transcriptome-wide intron retention and aberrant isoforms—notably of cell-cycle and DNA-repair (Fanconi anemia/HR) genes and of ATF4—causing DNA damage, mitotic defects, and senescence [PMID:33579912, PMID:30604754, PMID:35305370, PMID:39695328]. Through methylation of non-histone substrates PRMT5 drives oncogenic and stress-response signaling: it activates AKT1 by methylating R391 to enable membrane translocation [PMID:34103528, PMID:35803962], stabilizes the ferroptosis-protective GPX4 at R152 by blocking Cullin1-FBW7 ubiquitination [PMID:40033101], suppresses Hippo signaling by methylating MST2 at R461/R467 [PMID:37905571], dampens cGAS-STING antiviral sensing by methylating cGAS at R124 [PMID:33762328], and methylates SMAD4 (R361), ALKBH5 (R316), 53BP1, KLF5 (R41), FoxO1, KEAP1, and the D2 dopamine receptor to control EMT, m6A-dependent gene expression, NHEJ repair, and other programs [PMID:32759981, PMID:37380368, PMID:35278676, PMID:36991117, PMID:26554819, PMID:37883229, PMID:39781264, PMID:37461162]. PRMT5 activity is tuned by phosphorylation—Src at Y324 blocks SAM binding and inhibits NHEJ [PMID:32759981], LKB1 at T132/T139/T144 modulates cofactor binding [PMID:30289978], and MST4 at S439/S463 stimulates activity and METTL3 engagement [PMID:40158218]—and by the metabolite MTA, which competitively inhibits PRMT5 when MTAP is deleted, generating a hypomorphic state and a selective vulnerability also extending to MAT2A and RIOK1 [PMID:26912360, PMID:26912361, PMID:27068473, PMID:33450196]. Genetic ablation studies establish essential developmental and immune roles in myelination, B and T cell development, germ cell specification, and myogenesis [PMID:30026560, PMID:30604754, PMID:32328070, PMID:31533925].","teleology":[{"year":1996,"claim":"Before any enzymatic role was known, the question was what cellular process the PRMT5 ortholog participates in; work in fission yeast placed Skb1 within Ras/PAK morphology-control signaling.","evidence":"Yeast two-hybrid and in vivo ternary complex with Shk1 (PAK) and Cdc42, plus genetic epistasis in S. pombe","pmids":["8943016"],"confidence":"Medium","gaps":["No biochemical demonstration of methyltransferase activity at this stage","Human ortholog role not yet tested"]},{"year":1998,"claim":"Whether the yeast and human proteins are functionally equivalent and how they affect cell division was unknown; complementation showed conservation and linked the protein to mitotic inhibition via the Cdc2 complex.","evidence":"Genetic complementation of S. pombe skb1 by human SKB1Hs, epistasis with Shk1/Wee1, co-IP with Cdc2","pmids":["9843966"],"confidence":"Medium","gaps":["Mechanism of mitotic regulation in human cells unaddressed","No direct substrate identified"]},{"year":1999,"claim":"The founding question of molecular activity was answered: PRMT5 is a bona fide methyltransferase, establishing the enzymatic identity that underlies all later work.","evidence":"AdoMet cross-linking, in vitro methylation of histones H2A/H4 and MBP, active-site mutagenesis, co-IP with Jak2","pmids":["10531356"],"confidence":"High","gaps":["Symmetric vs asymmetric dimethylation specificity not yet defined","Physiological substrates beyond in vitro assays unknown"]},{"year":2001,"claim":"How PRMT5 activity is regulated was unclear; stress-responsive control of localization and activity was shown to be conserved from yeast to human.","evidence":"Fluorescence localization and in vitro activity under hyperosmotic stress in S. pombe with human protein complementation","pmids":["11278267"],"confidence":"Medium","gaps":["Molecular signal coupling stress to activity not defined","Relevance to mammalian cells untested"]},{"year":2016,"claim":"A central therapeutic question—why PRMT5 is selectively essential in certain cancers—was answered by showing MTAP loss raises MTA, which competitively inhibits PRMT5, creating a hypomorphic, dependency-prone state.","evidence":"Metabolomics, biochemical methyltransferase inhibition by MTA, shRNA screens across cancer lines, isogenic MTAP rescue; extended to MAT2A and RIOK1 vulnerabilities","pmids":["26912360","26912361","27068473"],"confidence":"High","gaps":["Which substrates are most rate-limiting under partial inhibition not resolved","Did not define adaptor-level substrate routing"]},{"year":2017,"claim":"The structural basis of obligate complex formation and processive dimethylation was unknown; the PRMT5:MEP50 heterooctamer structure defined cofactor and substrate recognition.","evidence":"Crystal structure of human PRMT5:MEP50 with SAM analog and substrate peptide","pmids":["28271477"],"confidence":"High","gaps":["Does not explain how diverse adaptors select substrates","Regulatory phosphorylation effects not captured"]},{"year":2018,"claim":"Two questions—how upstream kinases tune activity and how PRMT5 controls cell differentiation epigenetically—were addressed, linking LKB1 phosphorylation to cofactor binding and H4R3me2s to myelination.","evidence":"Kinase assays and PRMT5 mutagenesis (T132/T139/T144); conditional KO and purified-histone assays establishing H4R3me2s in oligodendrocyte differentiation","pmids":["30289978","30026560"],"confidence":"High","gaps":["Stoichiometry and dynamics of LKB1 phosphorylation in vivo unclear","Full set of differentiation-relevant loci not mapped"]},{"year":2019,"claim":"The scope of cellular symmetric dimethylation and PRMT5's developmental requirement were defined, identifying its writer/reader pathway components and an essential role in B cell development and splicing fidelity.","evidence":"CRISPR screen identifying MEP50, PPP4C, SMNDC1, SRSF3; conditional B-cell KO with RNA-seq splicing analysis and p53-dependency crosses; zebrafish KO defining germline substrates Zili/Vasa","pmids":["30916320","30604754","31533925"],"confidence":"High","gaps":["Degree of PRMT1 redundancy across tissues not quantified","Direct splicing substrate map in B cells incomplete"]},{"year":2020,"claim":"How phosphorylation gates PRMT5 in DNA repair and how PRMT5 restrains innate immunity were answered, revealing Src-Y324 control of SAM binding and methylation-dependent suppression of cGAS/STING and antigen presentation.","evidence":"Y324 mutagenesis and SAM-binding assays with NHEJ readouts; PRMT5 knockdown/inhibition with IFN, NLRC5/MHCI readouts in mouse models; T-cell conditional KO defining gamma-chain dependency","pmids":["32759981","32641491","32328070"],"confidence":"Medium","gaps":["Direct methylation sites on 53BP1 not defined","In vivo immune effects rest on single-lab models"]},{"year":2021,"claim":"A major mechanistic expansion connected PRMT5 to oncogenic signaling, splicing, and genome stability: methylation of AKT1-R391 and cGAS-R124, the adaptor-motif logic of substrate recruitment, and SAM/splicing-driven DNA damage in MTAP-null cells.","evidence":"In vitro methylation/mutagenesis and membrane-translocation/kinase assays (AKT1); structural and mutagenic mapping of the conserved adaptor motif; MAT2A inhibitor with RNA-seq/proteomics; orthogonal PRMT5 inhibitors with patient-derived GBM RNA-seq; RNF168/SMURF2 H2AX-stability cascade; cGAS DNA-binding and HSV-1 models; catalytic-dead rescue separating scaffold from enzymatic vascular roles; EZH2 cooperation at CDKN2B","pmids":["34103528","35803962","34358446","33450196","33579912","31533041","33762328","34153034","33664859"],"confidence":"High","gaps":["Which substrate methylations dominate the cancer dependency unresolved","Scaffold vs catalytic contributions not separated for most loci"]},{"year":2022,"claim":"PRMT5 was placed at the crossroads of metabolism, ferroptosis, m6A biology, and inflammation through methylation of KEAP1, ALKBH5, SMAD4, and NF-kB p65, and through histone-mark control of PD-L1.","evidence":"Methylation/co-IP and functional ferroptosis, m6A, EMT/metastasis, and VCAM-1 inflammation readouts; ChIP of H4R3me2s at the CD274 promoter","pmids":["37380368","35278676","36991117","35379776","35111150"],"confidence":"Medium","gaps":["Individual methylation sites mostly mapped in single labs","Cross-pathway integration in vivo not established"]},{"year":2023,"claim":"The non-histone substrate repertoire broadened to control Hippo signaling, autophagy, lipid metabolism, and protein stability, while a Smad3-directed H3R2me2s-to-H3K4me3 relay was defined in fibrosis.","evidence":"Site-specific methylation and functional assays for MST2-R461/467, ULK1-R532, FoxO1, SREBP1a, KLF5-R41, G3BP2-R468; fibroblast-specific KO with ChIP defining the WDR5/MLL1 hand-off at the alpha-SMA promoter; STC2 and DNA-repair coupling","pmids":["37905571","37400460","37883229","37334900","37461162","36878903","38503742","36764215"],"confidence":"High","gaps":["Tissue specificity of each substrate methylation not generalized","Most non-histone sites await structural confirmation"]},{"year":2025,"claim":"Recent work cemented PRMT5 control over ferroptosis and DNA repair via protein-stability switches and a phosphorylation-driven METTL3 axis, refining how methylation determines substrate ubiquitination and damage-site recruitment.","evidence":"GPX4-R152 methylation blocking Cullin1-FBW7 ubiquitination; ALKBH5-R316 methylation promoting TRIM28 degradation and CD276-driven immune evasion; MST4 phosphorylation of PRMT5 stimulating METTL3-R36 methylation and RAD51-dependent HR repair","pmids":["40033101","39781264","40158218"],"confidence":"Medium","gaps":["Interplay between competing E3 ligases context-dependent","MST4-PRMT5-METTL3 axis validated in a single cancer setting"]},{"year":null,"claim":"It remains unresolved which of PRMT5's many histone and non-histone methylation events are rate-limiting for its cancer dependency and how scaffolding versus catalytic functions are partitioned across tissues.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified hierarchy of physiologically dominant substrates","Adaptor-level substrate routing not mapped genome-wide in human cells","Separation of enzymatic from scaffold roles only shown for vascular morphogenesis"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,6,11,12,17,30,36]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,6,11,36]},{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[17,23,32]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[3,21,32]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[11,33]}],"pathway":[{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[12,15,24,29,44]},{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[17,19,23,32]},{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[9,13,39,42]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[11,30,22]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[10,18,26,24]},{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[1,14,16]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[33,47]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[20,36]}],"complexes":["PRMT5:MEP50/WDR77 methylosome"],"partners":["WDR77","CLNS1A","RIOK1","COPR5","EZH2","TBL2","SMAD3","METTL3"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O14744","full_name":"Protein arginine N-methyltransferase 5","aliases":["72 kDa ICln-binding protein","Histone-arginine N-methyltransferase PRMT5","Jak-binding protein 1","Shk1 kinase-binding protein 1 homolog","SKB1 homolog","SKB1Hs"],"length_aa":637,"mass_kda":72.7,"function":"Arginine methyltransferase that can both catalyze the formation of omega-N monomethylarginine (MMA) and symmetrical dimethylarginine (sDMA), with a preference for the formation of MMA (PubMed:10531356, PubMed:11152681, PubMed:11747828, PubMed:12411503, PubMed:15737618, PubMed:17709427, PubMed:20159986, PubMed:20810653, PubMed:21081503, PubMed:21258366, PubMed:21917714, PubMed:22269951). Specifically mediates the symmetrical dimethylation of arginine residues in the small nuclear ribonucleoproteins Sm D1 (SNRPD1) and Sm D3 (SNRPD3); such methylation being required for the assembly and biogenesis of snRNP core particles (PubMed:11747828, PubMed:12411503, PubMed:17709427). Methylates SUPT5H and may regulate its transcriptional elongation properties (PubMed:12718890). May methylate the N-terminal region of MBD2 (PubMed:16428440). Mono- and dimethylates arginine residues of myelin basic protein (MBP) in vitro. May play a role in cytokine-activated transduction pathways. Negatively regulates cyclin E1 promoter activity and cellular proliferation. Methylates histone H2A and H4 'Arg-3' during germ cell development (By similarity). Methylates histone H3 'Arg-8', which may repress transcription (By similarity). Methylates the Piwi proteins (PIWIL1, PIWIL2 and PIWIL4), methylation of Piwi proteins being required for the interaction with Tudor domain-containing proteins and subsequent localization to the meiotic nuage (By similarity). Methylates RPS10. Attenuates EGF signaling through the MAPK1/MAPK3 pathway acting at 2 levels. First, monomethylates EGFR; this enhances EGFR 'Tyr-1197' phosphorylation and PTPN6 recruitment, eventually leading to reduced SOS1 phosphorylation (PubMed:21258366, PubMed:21917714). Second, methylates RAF1 and probably BRAF, hence destabilizing these 2 signaling proteins and reducing their catalytic activity (PubMed:21917714). Required for induction of E-selectin and VCAM-1, on the endothelial cells surface at sites of inflammation. Methylates HOXA9 (PubMed:22269951). Methylates and regulates SRGAP2 which is involved in cell migration and differentiation (PubMed:20810653). Acts as a transcriptional corepressor in CRY1-mediated repression of the core circadian component PER1 by regulating the H4R3 dimethylation at the PER1 promoter (By similarity). Methylates GM130/GOLGA2, regulating Golgi ribbon formation (PubMed:20421892). Methylates H4R3 in genes involved in glioblastomagenesis in a CHTOP- and/or TET1-dependent manner (PubMed:25284789). Symmetrically methylates POLR2A, a modification that allows the recruitment to POLR2A of proteins including SMN1/SMN2 and SETX. This is required for resolving RNA-DNA hybrids created by RNA polymerase II, that form R-loop in transcription terminal regions, an important step in proper transcription termination (PubMed:26700805). Along with LYAR, binds the promoter of gamma-globin HBG1/HBG2 and represses its expression (PubMed:25092918). Symmetrically methylates NCL (PubMed:21081503). Methylates p53/TP53; methylation might possibly affect p53/TP53 target gene specificity (PubMed:19011621). Involved in spliceosome maturation and mRNA splicing in prophase I spermatocytes through the catalysis of the symmetrical arginine dimethylation of SNRPB (small nuclear ribonucleoprotein-associated protein) and the interaction with tudor domain-containing protein TDRD6 (By similarity)","subcellular_location":"Cytoplasm; Nucleus; Chromosome; Golgi apparatus","url":"https://www.uniprot.org/uniprotkb/O14744/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/PRMT5","classification":"Common Essential","n_dependent_lines":1140,"n_total_lines":1208,"dependency_fraction":0.9437086092715232},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CLNS1A","stoichiometry":10.0},{"gene":"WDR3","stoichiometry":10.0},{"gene":"SMN1","stoichiometry":4.0},{"gene":"HNRNPH1","stoichiometry":0.2},{"gene":"RIOK1","stoichiometry":0.2},{"gene":"SNRPB","stoichiometry":0.2},{"gene":"SNRPF","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/PRMT5","total_profiled":1310},"omim":[{"mim_id":"620567","title":"ZINC FINGER PROTEIN 507; ZNF507","url":"https://www.omim.org/entry/620567"},{"mim_id":"617754","title":"RIO KINASE 2; RIOK2","url":"https://www.omim.org/entry/617754"},{"mim_id":"617753","title":"RIO KINASE 1; RIOK1","url":"https://www.omim.org/entry/617753"},{"mim_id":"617684","title":"Ly1 ANTIBODY-REACTIVE PROTEIN; LYAR","url":"https://www.omim.org/entry/617684"},{"mim_id":"614206","title":"CHROMATIN TARGET OF PRMT1; CHTOP","url":"https://www.omim.org/entry/614206"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PRMT5"},"hgnc":{"alias_symbol":["SKB1Hs"],"prev_symbol":["HRMT1L5","SKB1"]},"alphafold":{"accession":"O14744","domains":[{"cath_id":"3.20.20.150","chopping":"15-162_178-218","consensus_level":"high","plddt":93.9551,"start":15,"end":218},{"cath_id":"3.40.50.150","chopping":"320-435","consensus_level":"high","plddt":96.2469,"start":320,"end":435},{"cath_id":"2.70.160.11","chopping":"467-635","consensus_level":"high","plddt":96.2151,"start":467,"end":635}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O14744","model_url":"https://alphafold.ebi.ac.uk/files/AF-O14744-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O14744-F1-predicted_aligned_error_v6.png","plddt_mean":93.31},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PRMT5","jax_strain_url":"https://www.jax.org/strain/search?query=PRMT5"},"sequence":{"accession":"O14744","fasta_url":"https://rest.uniprot.org/uniprotkb/O14744.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O14744/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O14744"}},"corpus_meta":[{"pmid":"26912360","id":"PMC_26912360","title":"MTAP 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choroidal neovascularization.","date":"2023","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/36720900","citation_count":12,"is_preprint":false},{"pmid":"39499734","id":"PMC_39499734","title":"TBL2 Promotes Tumorigenesis via PRMT5/WDR77-Mediated AKT Activation in Breast Cancer.","date":"2024","source":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/39499734","citation_count":11,"is_preprint":false},{"pmid":"38105619","id":"PMC_38105619","title":"Alpha-synuclein promotes PRMT5-mediated H4R3me2s histone methylation by interacting with the BAF complex.","date":"2023","source":"The FEBS journal","url":"https://pubmed.ncbi.nlm.nih.gov/38105619","citation_count":11,"is_preprint":false},{"pmid":"37782774","id":"PMC_37782774","title":"Resistance to PRMT5-targeted therapy in mantle cell lymphoma.","date":"2024","source":"Blood advances","url":"https://pubmed.ncbi.nlm.nih.gov/37782774","citation_count":10,"is_preprint":false},{"pmid":"37663901","id":"PMC_37663901","title":"PRMT1 and PRMT5: on the road of homologous recombination and non-homologous end joining.","date":"2022","source":"Genome instability & disease","url":"https://pubmed.ncbi.nlm.nih.gov/37663901","citation_count":10,"is_preprint":false},{"pmid":"38684324","id":"PMC_38684324","title":"Identification and validation of anti-protein arginine methyltransferase 5 (PRMT5) antibody as a novel biomarker for systemic sclerosis (SSc).","date":"2024","source":"Annals of the rheumatic diseases","url":"https://pubmed.ncbi.nlm.nih.gov/38684324","citation_count":9,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":47650,"output_tokens":13274,"usd":0.17103,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":24877,"output_tokens":5635,"usd":0.13263,"stage2_stop_reason":"end_turn"},"total_usd":0.30366,"stage1_batch_id":"msgbatch_01CNoDbkChHEkgrJnL7BwtGJ","stage2_batch_id":"msgbatch_016Y4x9E9Wg5VQDANj9quSQD","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1999,\n      \"finding\": \"Human PRMT5 (JBP1/SKB1Hs) is a protein methyltransferase that can be cross-linked to radiolabeled S-adenosylmethionine (AdoMet) and methylates histones H2A and H4 as well as myelin basic protein in vitro. Conserved motifs implicated in AdoMet binding are required for activity, as substitution mutants in this region show little or no methyltransferase activity. PRMT5 co-immunoprecipitates with Jak2 and several other proteins that serve as methyl-group acceptors.\",\n      \"method\": \"AdoMet cross-linking, in vitro methyltransferase assay, active-site mutagenesis, co-immunoprecipitation, yeast two-hybrid\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro enzymatic assay with radiolabeled cofactor, active-site mutagenesis, and protein interaction confirmed by co-IP, founding paper\",\n      \"pmids\": [\"10531356\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"The human homolog SKB1Hs can functionally replace fission yeast Skb1 in S. pombe, indicating evolutionary conservation of function. Fission yeast Skb1 negatively regulates mitosis by a mechanism independent of Cdc25 but at least partially dependent on Shk1 and Wee1; Skb1 and Shk1 biochemically associate with Cdc2 in S. pombe, suggesting inhibition of mitosis through interaction with the Cdc2 complex.\",\n      \"method\": \"Genetic complementation, genetic epistasis, biochemical co-immunoprecipitation with Cdc2\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis combined with biochemical co-IP in yeast model, functional conservation shown by complementation\",\n      \"pmids\": [\"9843966\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"Fission yeast Skb1 (ortholog of human PRMT5) interacts with Shk1 (PAK homolog) via the N-terminal regulatory domain of Shk1 at a site distinct from the Cdc42-binding region; Skb1, Shk1 and Cdc42 can form a ternary complex in vivo. Skb1 positively modulates Shk1 function and acts as a component of the morphology-control branch of the Ras signaling cascade.\",\n      \"method\": \"Yeast two-hybrid, in vivo co-immunoprecipitation (ternary complex), genetic epistasis\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — two-hybrid plus in vivo complex formation and genetic epistasis, yeast ortholog\",\n      \"pmids\": [\"8943016\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Fission yeast Skb1 localizes to cell ends, sites of septation, and nuclei; hyperosmotic shock causes delocalization from cell ends and nuclei and stimulates Skb1 protein methyltransferase activity. The methyltransferase activity of the human homolog Skb1Hs is similarly stimulated by hyperosmotic stress in fission yeast, indicating evolutionary conservation of the stress-responsive activity regulation.\",\n      \"method\": \"Subcellular localization by fluorescence microscopy, in vitro methyltransferase activity assay under osmotic stress, functional complementation in yeast\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization imaging combined with enzymatic activity measurement under defined stress conditions, conservation confirmed with human protein\",\n      \"pmids\": [\"11278267\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Loss of MTAP leads to intracellular accumulation of methylthioadenosine (MTA), which specifically and potently inhibits PRMT5 enzymatic activity. MTAP-null cells therefore display a hypomorphic PRMT5 state and selective dependence on PRMT5 and its binding partner WDR77. Reconstitution of MTAP in MTAP-deficient cells rescues PRMT5 dependence.\",\n      \"method\": \"Metabolomic profiling, biochemical methyltransferase inhibition assays (MTA vs. PRMT5), shRNA screening across 390 cancer cell lines, isogenic cell line rescue experiments\",\n      \"journal\": \"Science (New York, N.Y.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — biochemical enzymatic inhibition assay combined with metabolomics and genetic rescue, independently replicated in two concurrent Science papers (PMIDs 26912360 and 26912361)\",\n      \"pmids\": [\"26912360\", \"26912361\", \"27068473\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"MTA is a potent and selective inhibitor of PRMT5 among a panel of methyltransferases. MAT2A, which produces the PRMT5 substrate SAM, is also a synthetic lethal target in MTAP-deleted cells because MAT2A depletion reduces SAM levels and further attenuates PRMT5 methylation activity. RIOK1, a PRMT5 co-complex protein, is also a vulnerability in MTAP-deleted cells.\",\n      \"method\": \"Biochemical methyltransferase enzyme panel profiling, metabolomic studies, shRNA screening, co-complex identification\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — enzyme panel biochemical profiling plus metabolomics and genetic depletion, replicated across multiple laboratories\",\n      \"pmids\": [\"27068473\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"The PRMT5:MEP50 complex forms a 453 kDa heterooctamer. Crystal structures of this complex bound to an S-adenosylmethionine analog and a substrate peptide reveal the mechanism of substrate recognition and procession to dimethylation.\",\n      \"method\": \"Crystal structure determination of human PRMT5:MEP50 complex with SAM analog and substrate peptide\",\n      \"journal\": \"Sub-cellular biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structure of the complex with cofactor and substrate, provides atomic-level mechanistic insight\",\n      \"pmids\": [\"28271477\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"LKB1 directly interacts with and phosphorylates PRMT5 at T132, T139 and T144 residues in its TIM-barrel domain. Point mutations T139A/T144A drastically reduce PRMT5 methyltransferase activity, likely by disrupting interaction with regulatory cofactors MEP50, pICln and RiOK1. Modulation of LKB1 expression alters PRMT5 activity.\",\n      \"method\": \"Co-immunoprecipitation, in vitro kinase assay identifying phosphorylation sites, point mutagenesis of PRMT5, methyltransferase activity assay\",\n      \"journal\": \"International journal of cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal co-IP, site-directed mutagenesis, and activity assays in single laboratory\",\n      \"pmids\": [\"30289978\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"PRMT5 functions in complex with MEP50/WDR77 and is responsible for the vast majority of symmetric dimethylarginine in cells. A CRISPR/Cas9 screen identified PRMT5, MEP50/WDR77, PPP4C, SMNDC1, and SRSF3 as components of the PRMT5 writer/reader pathway. Loss of PRMT1 (the major asymmetric arginine methyltransferase) also sensitizes cells to PRMT5 inhibition, demonstrating partial redundancy between the PRMT5 and PRMT1 pathways.\",\n      \"method\": \"CRISPR/Cas9 genetic screen, combinatorial inhibitor treatment, genetic epistasis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genome-wide CRISPR screen with functional follow-up, single lab but multiple cell models\",\n      \"pmids\": [\"30916320\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"PRMT5 is phosphorylated at residue Y324 by Src kinase, which suppresses PRMT5 activity by preventing its binding to the methyl donor S-adenosyl-L-methionine. PRMT5 activity promotes non-homologous end joining (NHEJ) DNA repair by methylating and stabilizing 53BP1; Src-mediated phosphorylation of PRMT5 during DNA damage inhibits NHEJ and promotes apoptosis.\",\n      \"method\": \"Site-specific phosphorylation assay, mutagenesis of Y324, SAM-binding assay, co-immunoprecipitation of PRMT5 with 53BP1, NHEJ repair assays, cell survival after DNA damage\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis of phosphorylation site with functional methyltransferase and DNA repair readouts, single lab\",\n      \"pmids\": [\"32759981\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"PRMT5 methylation of IFI16/IFI204 (components of the cGAS/STING pathway) attenuates cytosolic DNA-induced IFN and chemokine expression in melanoma cells. PRMT5 also inhibits NLRC5 transcription, reducing MHC class I antigen presentation. PRMT5 knockdown augments IFN and chemokine production and increases MHC class I abundance.\",\n      \"method\": \"PRMT5 knockdown (shRNA), pharmacological inhibition (GSK3326595), measurement of IFN/chemokine production, NLRC5 and MHCI expression, immunocompetent vs immunocompromised mouse models\",\n      \"journal\": \"Science translational medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic and pharmacological inhibition with multiple pathway readouts, in vivo validation, single lab\",\n      \"pmids\": [\"32641491\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 promotes AKT1 activation by catalyzing symmetric dimethylation of AKT1 at arginine 391 (R391). R391 methylation cooperates with PIP3 to relieve the PH-in conformation of AKT1, enabling its translocation to the plasma membrane and subsequent activation by PDK1 and mTORC2. Deficiency in AKT1-R391 methylation significantly suppresses AKT1 kinase activity and tumorigenesis.\",\n      \"method\": \"In vitro methylation assay, mutagenesis of AKT1-R391, AKT1 membrane translocation assay, kinase activity assay, co-immunoprecipitation with PDK1/mTORC2, xenograft tumor models\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vitro methylation assay plus mutagenesis plus membrane translocation and kinase activity assays, corroborated by two independent papers (PMIDs 34103528 and 35803962)\",\n      \"pmids\": [\"34103528\", \"35803962\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 uses modular adaptor proteins (CLNS1A/pICln, RIOK1, and COPR5) for substrate recruitment through an evolutionarily conserved peptide motif shared among all three adaptors. This motif is necessary and sufficient for interaction with PRMT5. Disruption of the PRMT5-adaptor interface impairs methylation of adaptor-recruited substrates including spliceosome Sm proteins, histones, and ribosomal complexes, affects Sm spliceosome activity leading to intron retention, and impairs growth of MTAP-null tumor cells.\",\n      \"method\": \"Structural resolution of the PRMT5-adaptor interface, mutagenesis of the binding motif, methylation assays of adaptor-recruited substrates, RNA splicing assays, MTAP-null cell growth assays\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — structural resolution combined with mutagenesis, substrate methylation assays, and functional splicing readout in one rigorous study\",\n      \"pmids\": [\"34358446\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 regulates the expression of the E3 ubiquitin ligase RNF168, thereby stabilizing H2AX. Suppression of PRMT5 (e.g., in MTAP-deficient cells) reduces RNF168 expression, leading to destabilization of H2AX by E3 ubiquitin ligase SMURF2, resulting in higher levels of spontaneous and genotoxic-agent-induced DNA damage.\",\n      \"method\": \"shRNA knockdown of PRMT5/RNF168/SMURF2, co-immunoprecipitation to show RNF168 and SMURF2 interactions with H2AX, H2AX stability assays, DNA damage measurement in MTAP-deficient glioblastoma cells\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic knockdown cascade with co-IP for protein interactions, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"31533041\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MAT2A inhibition reduces SAM levels, which attenuates PRMT5 activity, causing widespread splicing perturbations (particularly of cell cycle genes) and subsequent DNA damage and mitotic defects in MTAP-null cells.\",\n      \"method\": \"Potent MAT2A inhibitor characterization, RNA sequencing, proteomics, measurement of SAM levels, DNA damage and mitotic defect assays in HCT116 MTAP-/- cells\",\n      \"journal\": \"Cancer cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — biochemical inhibitor with mechanistic profiling by RNA-seq, proteomics, and functional assays, rigorous study\",\n      \"pmids\": [\"33450196\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 inhibition causes widespread disruption of mRNA splicing across the transcriptome in glioblastoma, particularly affecting cell cycle gene products, consistent with its role in methylating spliceosome components.\",\n      \"method\": \"Pharmacological inhibition with two orthogonal PRMT5 inhibitors (GSK591 and LLY-283), RNA sequencing of 46 patient-derived GBM stem cell cultures, in vivo brain-penetrant inhibitor study\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — two orthogonal inhibitors, large patient-derived cohort, RNA-seq mechanistic readout, in vivo validation\",\n      \"pmids\": [\"33579912\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 inhibition in GBM neurospheres causes G1 cell cycle arrest through upregulation of p27 and hypophosphorylation of retinoblastoma protein, leading to senescence. Chromatin immunoprecipitation revealed that PRMT5 regulates PTEN expression in GBM neurospheres via methylation, controlling Akt and ERK activity; PTEN is identified as a downstream target of PRMT5 in GBM neurospheres.\",\n      \"method\": \"shRNA knockdown, Human Phospho-Kinase Array, chromatin immunoprecipitation-PCR for PTEN promoter, cell cycle analysis, in vivo intracranial tumor model\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-PCR plus phospho-kinase array plus in vivo model, single lab\",\n      \"pmids\": [\"27292259\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"PRMT5 methylates histone H4R3 (H4R3me2s) to catalyze symmetric methylation critical for oligodendrocyte differentiation and developmental myelination. Decreased H4R3me2s upon PRMT5 loss is followed by increased nuclear H4K5 acetylation; pharmacological inhibition of histone acetyltransferases rescues the differentiation defect, establishing a cross-talk between histone arginine methylation and lysine acetylation.\",\n      \"method\": \"Pharmacological inhibition, CRISPR/Cas9 knockout, conditional genetic ablation (Prmt5 conditional KO in progenitors), histone modification analysis with purified histones, differentiation/survival assays in oligodendrocyte progenitors and mice\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — multiple genetic and pharmacological approaches with mechanistic histone crosstalk validated in purified histones and in vivo mouse model\",\n      \"pmids\": [\"30026560\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Arginine methyltransferase PRMT5 directly binds cGAS and catalyzes symmetric dimethylation of cGAS at Arg124 (R124). This methylation attenuates cGAS-mediated antiviral immune response by blocking the DNA-binding ability of cGAS.\",\n      \"method\": \"Co-immunoprecipitation (PRMT5–cGAS interaction), in vitro methylation assay identifying R124, DNA-binding assay showing blockade, in vivo HSV-1 infection model with PRMT5 inhibitors\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP plus methylation site identification plus functional DNA-binding assay, single lab\",\n      \"pmids\": [\"33762328\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PRMT5 inhibition in lung cancer reduces symmetric dimethylation of histone H4R3 (H4R3me2s) at the CD274 (PD-L1) promoter locus, thereby de-repressing CD274 gene expression and increasing PD-L1 on tumor cells, activating the PD1/PD-L1 axis and eliminating CD8+ T cell anti-tumor immunity.\",\n      \"method\": \"ChIP analysis of H4R3me2s at CD274 promoter, shRNA knockdown, PRMT5 inhibitor treatment, in vitro and in vivo measurement of PD-L1 expression\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP assay demonstrating direct histone mark at CD274 promoter plus functional immune readout, single lab\",\n      \"pmids\": [\"35111150\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PRMT5 methylates KEAP1, downregulating NRF2 and its downstream targets. In TNBC with high ferrous levels, this PRMT5-mediated NRF2 suppression inhibits the HMOX1 pathway and promotes ferroptosis resistance by slowing ferrous import.\",\n      \"method\": \"Biochemical assays for KEAP1 methylation by PRMT5, co-IP, measurement of NRF2 targets and cellular ferrous levels, ferroptosis assays in TNBC vs non-TNBC cells\",\n      \"journal\": \"Journal for immunotherapy of cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — methylation and co-IP assays with functional ferroptosis readout, single lab\",\n      \"pmids\": [\"37380368\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PRMT5 promotes ALKBH5 nuclear translocation by methylating ALKBH5 at an arginine residue, enhancing ALKBH5-mediated removal of m6A methylation from BRCA1 mRNA, stabilizing BRCA1 mRNA, increasing DNA repair competency, and decreasing doxorubicin efficacy in breast cancer cells.\",\n      \"method\": \"PRMT5 inhibition and shRNA knockdown, m6A quantification, ALKBH5 subcellular fractionation/localization, BRCA1 mRNA stability measurement, DNA repair assays\",\n      \"journal\": \"Molecular therapy : the journal of the American Society of Gene Therapy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — subcellular fractionation with functional mRNA stability and DNA repair readouts, single lab\",\n      \"pmids\": [\"35278676\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PRMT5 interacts with SMAD4 and methylates it at R361 upon TGF-β1 treatment. R361 methylation is required for SMAD complex formation and nuclear import, driving EMT and colorectal cancer metastasis. SMAD4 R361A mutation abolishes PRMT5/TGF-β1-induced metastasis.\",\n      \"method\": \"Mass spectrometry identification of R361 methylation, co-immunoprecipitation, immunofluorescence, SMAD complex formation assay, nuclear import assay, EMT and metastasis assays with mutant SMAD4\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — MS-based methylation site ID plus co-IP/IF with mutagenesis functional validation, single lab\",\n      \"pmids\": [\"36991117\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 functionally associates with EZH2 (confirmed by co-IP and GST pulldown). PRMT5 deposits H4R3me2s and H3R8me2s marks at the CDKN2B promoter; knockdown reduces these marks and the accompanying CpG methylation, reactivating CDKN2B expression. PRMT5 interaction with EZH2 leads to enhanced EZH2 binding and H3K27me3 at the CDKN2B locus.\",\n      \"method\": \"Co-immunoprecipitation, GST pulldown, ChIP assay (H4R3me2s, H3R8me2s, H3K27me3 at CDKN2B promoter), bisulfite sequencing, luciferase reporter\",\n      \"journal\": \"Theranostics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal co-IP and GST pulldown plus ChIP with multiple marks, single lab\",\n      \"pmids\": [\"33664859\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"PRMT5 is required for B cell development and antibody responses in mice. PRMT5 prevents p53-dependent blocks at the Pro-B cell stage and p53-independent apoptosis in mature B cells during activation; it promotes germinal center expansion and ensures RNA splicing fidelity in germinal center B cells.\",\n      \"method\": \"Conditional B cell-specific Prmt5 knockout mice, flow cytometry, RNA-seq (splicing analysis), p53-dependency tested by genetic crosses\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional KO with defined cellular phenotypes at multiple B cell stages, RNA-seq mechanistic readout, rigorous genetic dissection of p53 dependence\",\n      \"pmids\": [\"30604754\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Zebrafish Prmt5 methylates germ cell-specific proteins Zili and Vasa (symmetric dimethylarginine) as well as histones H3R8me2s and H4R3me2s. Loss of Prmt5 reduces methylation of these substrates in gonads, downregulates Piwi pathway proteins, and causes germ cell apoptosis and failure of gonadal differentiation, leading to infertile male phenotype.\",\n      \"method\": \"Prmt5-null zebrafish model, immunostaining for H3R8me2s and H4R3me2s, western blot for Zili/Vasa methylation, gene expression analysis of meiosis/gonad genes\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo knockout with direct methylation substrate identification and functional phenotype, single lab in zebrafish model\",\n      \"pmids\": [\"31533925\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"PRMT5 deletion in T cells reduces expression of the common gamma chain (γc), impairing IL-7-mediated survival and IL-2-mediated TCR-induced proliferation. PRMT5 is required for NKT cell development and peripheral T cell maintenance, homeostatic survival, and lymphopenic expansion in vivo.\",\n      \"method\": \"T cell-specific conditional PRMT5 knockout mice, flow cytometry, in vitro cytokine signaling assays, in vivo lymphopenic expansion model\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean conditional KO with defined cellular and signaling phenotypes, single lab\",\n      \"pmids\": [\"32328070\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"PRMT5 methylates arginine residues in the third intracellular loop of the human D2 dopamine receptor. Mutation of these arginine residues reduces D2 receptor-mediated inhibition of cAMP signaling in HEK293T cells. In C. elegans, PRMT5 (prmt-5) promotes dopamine-mediated modulation of chemosensory and locomotory behaviors through the DOP-3 receptor.\",\n      \"method\": \"In vitro methylation assay of D2 receptor peptide by PRMT5, arginine-to-alanine mutagenesis of receptor, cAMP signaling assay in HEK293T cells, behavioral assays in prmt-5 C. elegans mutants\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro methylation assay plus mutagenesis plus functional cAMP and behavioral readouts, two model systems\",\n      \"pmids\": [\"26554819\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Menin and PRMT5 cooperate to suppress GLP1 receptor (GLP1R) transcript levels. In β-cells, PRMT5 (together with menin) suppresses PKA-mediated phosphorylation of FOXO1 and CREB downstream of GLP1 signaling, likely through arginine methyltransferase activity.\",\n      \"method\": \"Co-immunoprecipitation of menin-PRMT5 complex, gene expression analysis, phosphorylation assays for FOXO1 and CREB, small-molecule menin inhibitor rescue, ex vivo islet assays\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — co-IP and expression data with pharmacological manipulation, single lab, limited direct mutagenesis of PRMT5 activity\",\n      \"pmids\": [\"28270438\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 inhibition disrupts splicing of the ATF4 transcript, producing intron-retaining ATF4 mRNA that is detained in the nucleus, reducing cytoplasmic spliced ATF4 protein, downregulating ATF4 target genes, increasing oxidative stress, and inducing cellular senescence in AML cells.\",\n      \"method\": \"RNA sequencing, nuclear/cytoplasmic fractionation of ATF4 mRNA, ROS measurement, senescence assays, PRMT5 inhibitor treatment\",\n      \"journal\": \"Redox biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNA-seq with fractionation and functional oxidative stress readouts, single lab\",\n      \"pmids\": [\"35305370\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 symmetrically dimethylates MST2 (STK3) at R461 and R467 in its SARAH domain. This methylation suppresses MST2 autophosphorylation and kinase activity by blocking its homodimerization, inactivating the Hippo signaling pathway and promoting pancreatic cancer progression.\",\n      \"method\": \"In vitro methylation assay identifying R461/R467, co-immunoprecipitation, MST2 autophosphorylation assay, homodimerization assay, PRMT5 inhibitor (GSK3326595) in xenograft models\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro methylation with site ID plus functional kinase and dimerization assays, in vivo validation, single lab\",\n      \"pmids\": [\"37905571\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PRMT5 promotes symmetric dimethylation of NF-κB p65 at arginine 30 (R30) in vascular smooth muscle cells, leading to upregulation of VCAM-1 expression and macrophage adhesion. TMAO-induced Nox4-mediated ROS production drives PRMT5 expression, establishing a Nox4-PRMT5-VCAM-1 axis in TMAO-induced vascular inflammation.\",\n      \"method\": \"PRMT5 knockdown, VSMC-specific PRMT5 knockout mice, methylation assay of p65-R30, VCAM-1 expression and macrophage adhesion assays, ROS measurement\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — site-specific methylation identification plus in vivo conditional KO with functional inflammatory readout, single lab\",\n      \"pmids\": [\"35379776\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In cardiac fibroblasts, TGF-β stimulation promotes recruitment of a PRMT5/Smad3 complex to the α-SMA (ACTA2) promoter, increasing PRMT5-mediated H3R2 symmetric dimethylation. This mark is recognized by the WDR5/MLL1 methyltransferase complex, which then increases H3K4 trimethylation, enabling fibrotic gene transcription. Fibroblast-specific PRMT5 deletion reduces pressure overload-induced cardiac fibrosis in mice.\",\n      \"method\": \"ChIP assay of H3R2me2s at α-SMA promoter, Smad3 knockdown reducing H3R2me2s, co-IP of PRMT5/Smad3 complex, fibroblast-specific conditional KO mice, pressure overload model\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP demonstrating specific histone mark at promoter with Smad3 dependency, co-IP, and in vivo conditional KO with functional cardiac phenotype\",\n      \"pmids\": [\"38503742\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 methylates FoxO1 (symmetric dimethylarginine), destabilizing it. PRMT5 knockout in myoblasts increases total FoxO1 protein and promotes its cytoplasmic accumulation, activating autophagy and depleting lipid droplets, impairing muscle regeneration. Systemic autophagy inhibition in Prmt5MKO mice restores lipid droplets and moderately improves muscle regeneration.\",\n      \"method\": \"Myod1Cre-driven Prmt5 conditional KO mice, FoxO1 methylation and stability assays, subcellular fractionation, autophagy flux assays, lipid droplet quantification, genetic autophagy inhibition rescue\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional KO with methylation substrate identification, subcellular localization, and autophagy rescue, single lab\",\n      \"pmids\": [\"37883229\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 methylates SREBP1a at arginine residues, increasing its stability. Skeletal muscle-specific PRMT5 knockout reduces SREBP1a dimethylation and stability, impairing de novo lipogenesis. PRMT5 deletion also de-represses the Pnpla2 (ATGL) promoter via reduced H4R3me2s, elevating ATGL-mediated lipolysis. Double knockout of Pnpla2 and Prmt5 normalizes muscle mass and function.\",\n      \"method\": \"Skeletal muscle-specific Prmt5 KO mice, SREBP1a methylation and stability assays, ChIP of H4R3me2s at Pnpla2 promoter, double KO genetic rescue\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional KO with substrate methylation and ChIP, genetic rescue experiment, single lab\",\n      \"pmids\": [\"37334900\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TBL2 acts as a scaffolding protein that promotes PRMT5-WDR77 (MEP50) interaction. This enhanced interaction increases PRMT5 methyltransferase activity and AKT phosphorylation, promoting breast cancer cell proliferation.\",\n      \"method\": \"Proteomic analysis, co-immunoprecipitation of TBL2-PRMT5-WDR77 complex, methyltransferase activity assay, AKT phosphorylation measurement, in vitro and in vivo proliferation assays\",\n      \"journal\": \"Advanced science (Weinheim, Baden-Wurttemberg, Germany)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP for ternary complex plus functional methyltransferase and kinase activity assays, single lab\",\n      \"pmids\": [\"39499734\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PRMT5 catalyzes symmetric dimethylation of GPX4 at the conserved R152 residue. This methylation prolongs GPX4 half-life by preventing Cullin1-FBW7 E3 ligase binding to GPX4, thereby blocking ubiquitination-mediated GPX4 degradation and suppressing ferroptosis in cancer cells.\",\n      \"method\": \"In vitro methylation assay of GPX4-R152 by PRMT5, GPX4 half-life measurement, co-immunoprecipitation of GPX4 with FBW7 (with and without methylation), ubiquitination assay, PRMT5 inhibitor in vivo tumor models\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vitro methylation assay with site mutagenesis, protein stability and ubiquitination assays, co-IP demonstrating E3 ligase displacement, in vivo validation\",\n      \"pmids\": [\"40033101\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PRMT5 directly catalyzes symmetric dimethylation of ALKBH5 at R316 (meR316-ALKBH5), enhancing TRIM28-mediated ALKBH5 ubiquitination and degradation. Reduced ALKBH5 decreases m6A demethylation of the CD276 transcript 3' UTR, increasing CD276 mRNA stability and expression, facilitating colorectal cancer immune evasion by inhibiting cytotoxic T-cell function.\",\n      \"method\": \"In vitro methylation assay identifying R316, co-IP of ALKBH5 with TRIM28, ubiquitination assay, m6A quantification on CD276 transcript, mRNA stability assay, in vivo and in vitro immune evasion assays\",\n      \"journal\": \"Research (Washington, D.C.)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — methylation site identification, co-IP, ubiquitination and m6A assays in single lab\",\n      \"pmids\": [\"39781264\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 regulates PRMT5-mediated dimethylation of Zili (PIWI protein) and Vasa in zebrafish gonads, controls Piwi pathway protein expression, and thereby governs germ cell development; these represent direct non-histone substrates of PRMT5 in vertebrate germline.\",\n      \"method\": \"Prmt5-null zebrafish, immunostaining for symmetric arginine dimethylation of Zili/Vasa, gene expression profiling\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo KO with direct substrate methylation measurement in zebrafish ortholog model, single lab\",\n      \"pmids\": [\"31533925\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"STC2 interacts with PRMT5 and activates it, leading to increased H4R3me2s. Activated PRMT5 promotes DNA double-strand break repair through both homologous recombination and non-homologous end joining pathways, and participates in SLC7A11-mediated ferroptosis resistance in a PRMT5-dependent manner in esophageal squamous cell carcinoma.\",\n      \"method\": \"Co-immunoprecipitation of STC2-PRMT5, H4R3me2s western blot, DNA repair pathway assays (HR and NHEJ), SLC7A11 expression assays, in vivo validation\",\n      \"journal\": \"Redox biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP with functional enzymatic activity and DNA repair readouts, single lab\",\n      \"pmids\": [\"36764215\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 inhibition in multiple myeloma de-represses CASP1 expression (negatively correlated with PRMT5 levels), leading to CASP1-dependent pyroptosis. PRMT5 silences CASP1 via its histone methyltransferase activity (H4R3me2s).\",\n      \"method\": \"PRMT5 knockdown, PRMT5 inhibitor treatment, CASP1 expression measurement, pyroptosis markers (N-GSDMD, IL-1b, IL-18), correlation of PRMT5 and CASP1 expression\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — knockdown and inhibitor with pyroptosis markers, but direct ChIP of H4R3me2s at CASP1 promoter not reported in abstract\",\n      \"pmids\": [\"34531375\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 methylates KLF5 at arginine 41 (R41) in a methyltransferase-activity-dependent manner. This dimethylation stabilizes KLF5 protein by promoting the Akt/GSK3β signaling axis, reducing its degradation and maintaining lung cancer cell proliferation.\",\n      \"method\": \"Co-immunoprecipitation (PRMT5-KLF5), in vitro methylation assay (R41 site), protein stability assays, KLF5 downstream target analysis, in vivo xenograft with PRMT5 inhibition\",\n      \"journal\": \"Journal of cellular and molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP and methylation site identification with protein stability assay, single lab\",\n      \"pmids\": [\"37461162\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MST4 kinase, transactivated by NRF2, phosphorylates PRMT5 at S439 and S463 and promotes PRMT5 interaction with METTL3, stimulating PRMT5's methyltransferase activity. PRMT5 then methylates METTL3 at R36 (METTL3-R36me2); this methylation recruits METTL3 to DNA damage sites, promoting RAD51 recruitment for HR-mediated double-strand break repair and cisplatin resistance in ovarian cancer.\",\n      \"method\": \"In vitro phosphorylation assay (MST4 on PRMT5), co-IP showing increased PRMT5-METTL3 interaction upon phosphorylation, methylation assay identifying R36, ChIP showing METTL3 recruitment to DSB sites, RAD51 foci assay, xenograft model\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple in vitro biochemical assays with site identification and ChIP functional readout, single lab\",\n      \"pmids\": [\"40158218\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5-mediated methylation of G3BP2 at R468 (G3BP2-R468me2) enhances G3BP2 binding to the deubiquitinase USP7, promoting deubiquitination and stabilization of G3BP2, which activates ACLY and stimulates de novo lipogenesis and tumorigenesis in head and neck squamous carcinoma.\",\n      \"method\": \"Co-IP of G3BP2-USP7 interaction with and without PRMT5, methylation assay identifying R468, ubiquitination/deubiquitination assay, ACLY activity assay, lipogenesis measurement\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — methylation site identification, co-IP demonstrating USP7 interaction dependency, deubiquitination and lipogenic functional assays, single lab\",\n      \"pmids\": [\"36878903\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 inhibition in breast cancer stem cells disrupts splicing of DNA repair genes involved in Fanconi Anemia and homologous recombination pathways (including ATM, DDX11, EXO1, FAN1, SLX4, ATR, RAD17, RAD51D, RUVBL1), causing nuclear retention of intron-containing transcripts and production of non-canonical isoforms with compromised protein function rather than gene expression repression.\",\n      \"method\": \"RNA sequencing of PRMT5-inhibited BCSCs vs bulk cells, identification of skipped exon and retained intron events, nuclear vs cytoplasmic fractionation of transcripts, apoptosis assays\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNA-seq with nuclear fractionation mechanistic validation identifying specific splice events, single lab\",\n      \"pmids\": [\"39695328\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PRMT5 promotes vascular morphogenesis in zebrafish through transcriptional control of ETS transcription factors and adhesion proteins in endothelial cells. Using a catalytic dead PRMT5 mutant, it was demonstrated that methyltransferase activity is dispensable for vessel formation but required for blood cell formation; PRMT5 acts as a scaffold protein facilitating chromatin looping to regulate transcription during vascular morphogenesis.\",\n      \"method\": \"Zebrafish prmt5 loss-of-function, catalytic dead PRMT5 mutant rescue experiments, pharmacological methyltransferase inhibition, chromatin conformation assays (reporter gene analysis), ChIP\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — catalytic dead mutant compared to inhibitor clearly separates scaffolding vs enzymatic function, ChIP and chromatin architecture analysis, single lab in zebrafish model\",\n      \"pmids\": [\"34153034\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 catalyzes symmetric dimethylation of PRMT5 at CAMK2N1's promoter via H4R3me2s and H3R8me2s marks, repressing CAMK2N1 transcription in prostate cancer cells. This silencing promotes prostate cancer progression in vitro and in vivo.\",\n      \"method\": \"ChIP assay of H4R3me2s and H3R8me2s at CAMK2N1 promoter, shRNA knockdown and rescue, PRMT5 inhibitor, in vivo tumor growth assays\",\n      \"journal\": \"Molecular cancer\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — ChIP assay showing histone marks at promoter, but this paper is primarily about the circRNA axis; the PRMT5-specific mechanism is adequately supported but secondarily reported\",\n      \"pmids\": [\"35624451\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PRMT5 methylates ULK1 at R532 (monomethylation), suppressing ULK1 activation and attenuating autophagy. Loss or inhibition of PRMT5 removes this methylation, activating ULK1 and triggering cytoprotective autophagy. ULK1 inhibition blocks PRMT5-deficiency-induced autophagy and sensitizes cells to PRMT5 inhibitor.\",\n      \"method\": \"In vitro methylation assay (ULK1 R532), ULK1 activity assay, autophagy flux assays, ULK1 inhibitor and genetic ablation epistasis experiments, PRMT5 inhibitor sensitivity assays\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro methylation site identification plus functional kinase and autophagy assays with genetic epistasis, single lab\",\n      \"pmids\": [\"37400460\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Alpha-synuclein overexpression enhances BAF complex interaction with PRMT5, globally increasing H4R3me2s symmetric dimethylation. This results in H4R3me2s accumulation near the NRCAM transcription start site and negative regulation of NRCAM, a neuronal differentiation gene. ChIP-seq confirmed H4R3me2s accumulation at the NRCAM locus.\",\n      \"method\": \"Mass spectrometry interactome of nuclear alpha-synuclein (identifying BAF-PRMT5 interaction), ChIP-seq for H4R3me2s, transcriptomic analysis of NRCAM\",\n      \"journal\": \"The FEBS journal\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — interactome by MS and ChIP-seq, but PRMT5's enzymatic activity specifically driving the H4R3me2s change is inferred from the interaction rather than directly confirmed by PRMT5 mutagenesis\",\n      \"pmids\": [\"38105619\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PRMT5 is the principal type II protein arginine methyltransferase that, in obligate complex with MEP50/WDR77, catalyzes mono- and symmetric dimethylation of arginine on a broad set of histone (H2A, H4R3, H3R8) and non-histone substrates (AKT1-R391, GPX4-R152, SMAD4-R361, MST2-R461/467, cGAS-R124, ALKBH5-R316, ULK1-R532, 53BP1, KLF5-R41, FoxO1, D2 receptor, and others); substrate recruitment is mediated by adaptor proteins (pICln/CLNS1A, RIOK1, COPR5) sharing a conserved PRMT5-binding motif, and PRMT5 activity is regulated by phosphorylation (Src at Y324 inhibits; LKB1 at T132/T139/T144 modulates cofactor binding; MST4 at S439/S463 activates), by the metabolite MTA (which competitively inhibits PRMT5 when MTAP is deleted), and by scaffolding partners such as TBL2; through these activities PRMT5 controls RNA splicing fidelity, cell cycle progression, DNA damage repair (NHEJ and HR), ferroptosis resistance, AKT-driven oncogenic signaling, innate immune sensing (cGAS/STING), antigen presentation, autophagy, and developmental programs including myelination, B cell development, germ cell specification, and myogenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PRMT5 is the principal type II protein arginine methyltransferase that catalyzes mono- and symmetric dimethylation of arginine on histone and non-histone substrates, governing chromatin states, RNA splicing fidelity, cell cycle, DNA repair, and developmental programs [#0, #6]. It acts only in obligate complex with MEP50/WDR77, forming a 453 kDa heterooctamer whose crystal structure defines how cofactor binding and substrate peptide engagement drive processive dimethylation [#6], and its activity is augmented by scaffolds such as TBL2 that promote the PRMT5-WDR77 interaction [#35]. Substrate selection is conferred by a family of modular adaptors (CLNS1A/pICln, RIOK1, COPR5) that dock onto PRMT5 through a single conserved peptide motif necessary and sufficient for binding, directing methylation to spliceosomal Sm proteins, histones, and ribosomal complexes [#12]. On chromatin, PRMT5 deposits symmetric H4R3me2s and H3R8me2s marks—and, with Smad3, H3R2me2s—to repress or activate loci including CDKN2B, CD274/PD-L1, the alpha-SMA promoter, and oligodendrocyte differentiation genes, frequently in cooperation with EZH2 or the WDR5/MLL1 complex [#17, #19, #23, #32]. As a writer for the spliceosome it safeguards splicing fidelity, and its inhibition produces transcriptome-wide intron retention and aberrant isoforms—notably of cell-cycle and DNA-repair (Fanconi anemia/HR) genes and of ATF4—causing DNA damage, mitotic defects, and senescence [#15, #24, #29, #44]. Through methylation of non-histone substrates PRMT5 drives oncogenic and stress-response signaling: it activates AKT1 by methylating R391 to enable membrane translocation [#11], stabilizes the ferroptosis-protective GPX4 at R152 by blocking Cullin1-FBW7 ubiquitination [#36], suppresses Hippo signaling by methylating MST2 at R461/R467 [#30], dampens cGAS-STING antiviral sensing by methylating cGAS at R124 [#18], and methylates SMAD4 (R361), ALKBH5 (R316), 53BP1, KLF5 (R41), FoxO1, KEAP1, and the D2 dopamine receptor to control EMT, m6A-dependent gene expression, NHEJ repair, and other programs [#9, #20, #21, #22, #27, #33, #37, #41]. PRMT5 activity is tuned by phosphorylation—Src at Y324 blocks SAM binding and inhibits NHEJ [#9], LKB1 at T132/T139/T144 modulates cofactor binding [#7], and MST4 at S439/S463 stimulates activity and METTL3 engagement [#42]—and by the metabolite MTA, which competitively inhibits PRMT5 when MTAP is deleted, generating a hypomorphic state and a selective vulnerability also extending to MAT2A and RIOK1 [#4, #5, #14]. Genetic ablation studies establish essential developmental and immune roles in myelination, B and T cell development, germ cell specification, and myogenesis [#17, #24, #26, #25].\",\n  \"teleology\": [\n    {\n      \"year\": 1996,\n      \"claim\": \"Before any enzymatic role was known, the question was what cellular process the PRMT5 ortholog participates in; work in fission yeast placed Skb1 within Ras/PAK morphology-control signaling.\",\n      \"evidence\": \"Yeast two-hybrid and in vivo ternary complex with Shk1 (PAK) and Cdc42, plus genetic epistasis in S. pombe\",\n      \"pmids\": [\"8943016\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No biochemical demonstration of methyltransferase activity at this stage\", \"Human ortholog role not yet tested\"]\n    },\n    {\n      \"year\": 1998,\n      \"claim\": \"Whether the yeast and human proteins are functionally equivalent and how they affect cell division was unknown; complementation showed conservation and linked the protein to mitotic inhibition via the Cdc2 complex.\",\n      \"evidence\": \"Genetic complementation of S. pombe skb1 by human SKB1Hs, epistasis with Shk1/Wee1, co-IP with Cdc2\",\n      \"pmids\": [\"9843966\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of mitotic regulation in human cells unaddressed\", \"No direct substrate identified\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"The founding question of molecular activity was answered: PRMT5 is a bona fide methyltransferase, establishing the enzymatic identity that underlies all later work.\",\n      \"evidence\": \"AdoMet cross-linking, in vitro methylation of histones H2A/H4 and MBP, active-site mutagenesis, co-IP with Jak2\",\n      \"pmids\": [\"10531356\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Symmetric vs asymmetric dimethylation specificity not yet defined\", \"Physiological substrates beyond in vitro assays unknown\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"How PRMT5 activity is regulated was unclear; stress-responsive control of localization and activity was shown to be conserved from yeast to human.\",\n      \"evidence\": \"Fluorescence localization and in vitro activity under hyperosmotic stress in S. pombe with human protein complementation\",\n      \"pmids\": [\"11278267\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular signal coupling stress to activity not defined\", \"Relevance to mammalian cells untested\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"A central therapeutic question—why PRMT5 is selectively essential in certain cancers—was answered by showing MTAP loss raises MTA, which competitively inhibits PRMT5, creating a hypomorphic, dependency-prone state.\",\n      \"evidence\": \"Metabolomics, biochemical methyltransferase inhibition by MTA, shRNA screens across cancer lines, isogenic MTAP rescue; extended to MAT2A and RIOK1 vulnerabilities\",\n      \"pmids\": [\"26912360\", \"26912361\", \"27068473\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which substrates are most rate-limiting under partial inhibition not resolved\", \"Did not define adaptor-level substrate routing\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"The structural basis of obligate complex formation and processive dimethylation was unknown; the PRMT5:MEP50 heterooctamer structure defined cofactor and substrate recognition.\",\n      \"evidence\": \"Crystal structure of human PRMT5:MEP50 with SAM analog and substrate peptide\",\n      \"pmids\": [\"28271477\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not explain how diverse adaptors select substrates\", \"Regulatory phosphorylation effects not captured\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Two questions—how upstream kinases tune activity and how PRMT5 controls cell differentiation epigenetically—were addressed, linking LKB1 phosphorylation to cofactor binding and H4R3me2s to myelination.\",\n      \"evidence\": \"Kinase assays and PRMT5 mutagenesis (T132/T139/T144); conditional KO and purified-histone assays establishing H4R3me2s in oligodendrocyte differentiation\",\n      \"pmids\": [\"30289978\", \"30026560\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and dynamics of LKB1 phosphorylation in vivo unclear\", \"Full set of differentiation-relevant loci not mapped\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"The scope of cellular symmetric dimethylation and PRMT5's developmental requirement were defined, identifying its writer/reader pathway components and an essential role in B cell development and splicing fidelity.\",\n      \"evidence\": \"CRISPR screen identifying MEP50, PPP4C, SMNDC1, SRSF3; conditional B-cell KO with RNA-seq splicing analysis and p53-dependency crosses; zebrafish KO defining germline substrates Zili/Vasa\",\n      \"pmids\": [\"30916320\", \"30604754\", \"31533925\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Degree of PRMT1 redundancy across tissues not quantified\", \"Direct splicing substrate map in B cells incomplete\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"How phosphorylation gates PRMT5 in DNA repair and how PRMT5 restrains innate immunity were answered, revealing Src-Y324 control of SAM binding and methylation-dependent suppression of cGAS/STING and antigen presentation.\",\n      \"evidence\": \"Y324 mutagenesis and SAM-binding assays with NHEJ readouts; PRMT5 knockdown/inhibition with IFN, NLRC5/MHCI readouts in mouse models; T-cell conditional KO defining gamma-chain dependency\",\n      \"pmids\": [\"32759981\", \"32641491\", \"32328070\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct methylation sites on 53BP1 not defined\", \"In vivo immune effects rest on single-lab models\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"A major mechanistic expansion connected PRMT5 to oncogenic signaling, splicing, and genome stability: methylation of AKT1-R391 and cGAS-R124, the adaptor-motif logic of substrate recruitment, and SAM/splicing-driven DNA damage in MTAP-null cells.\",\n      \"evidence\": \"In vitro methylation/mutagenesis and membrane-translocation/kinase assays (AKT1); structural and mutagenic mapping of the conserved adaptor motif; MAT2A inhibitor with RNA-seq/proteomics; orthogonal PRMT5 inhibitors with patient-derived GBM RNA-seq; RNF168/SMURF2 H2AX-stability cascade; cGAS DNA-binding and HSV-1 models; catalytic-dead rescue separating scaffold from enzymatic vascular roles; EZH2 cooperation at CDKN2B\",\n      \"pmids\": [\"34103528\", \"35803962\", \"34358446\", \"33450196\", \"33579912\", \"31533041\", \"33762328\", \"34153034\", \"33664859\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which substrate methylations dominate the cancer dependency unresolved\", \"Scaffold vs catalytic contributions not separated for most loci\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"PRMT5 was placed at the crossroads of metabolism, ferroptosis, m6A biology, and inflammation through methylation of KEAP1, ALKBH5, SMAD4, and NF-kB p65, and through histone-mark control of PD-L1.\",\n      \"evidence\": \"Methylation/co-IP and functional ferroptosis, m6A, EMT/metastasis, and VCAM-1 inflammation readouts; ChIP of H4R3me2s at the CD274 promoter\",\n      \"pmids\": [\"37380368\", \"35278676\", \"36991117\", \"35379776\", \"35111150\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Individual methylation sites mostly mapped in single labs\", \"Cross-pathway integration in vivo not established\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"The non-histone substrate repertoire broadened to control Hippo signaling, autophagy, lipid metabolism, and protein stability, while a Smad3-directed H3R2me2s-to-H3K4me3 relay was defined in fibrosis.\",\n      \"evidence\": \"Site-specific methylation and functional assays for MST2-R461/467, ULK1-R532, FoxO1, SREBP1a, KLF5-R41, G3BP2-R468; fibroblast-specific KO with ChIP defining the WDR5/MLL1 hand-off at the alpha-SMA promoter; STC2 and DNA-repair coupling\",\n      \"pmids\": [\"37905571\", \"37400460\", \"37883229\", \"37334900\", \"37461162\", \"36878903\", \"38503742\", \"36764215\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tissue specificity of each substrate methylation not generalized\", \"Most non-histone sites await structural confirmation\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Recent work cemented PRMT5 control over ferroptosis and DNA repair via protein-stability switches and a phosphorylation-driven METTL3 axis, refining how methylation determines substrate ubiquitination and damage-site recruitment.\",\n      \"evidence\": \"GPX4-R152 methylation blocking Cullin1-FBW7 ubiquitination; ALKBH5-R316 methylation promoting TRIM28 degradation and CD276-driven immune evasion; MST4 phosphorylation of PRMT5 stimulating METTL3-R36 methylation and RAD51-dependent HR repair\",\n      \"pmids\": [\"40033101\", \"39781264\", \"40158218\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Interplay between competing E3 ligases context-dependent\", \"MST4-PRMT5-METTL3 axis validated in a single cancer setting\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved which of PRMT5's many histone and non-histone methylation events are rate-limiting for its cancer dependency and how scaffolding versus catalytic functions are partitioned across tissues.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified hierarchy of physiologically dominant substrates\", \"Adaptor-level substrate routing not mapped genome-wide in human cells\", \"Separation of enzymatic from scaffold roles only shown for vascular morphogenesis\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 6, 11, 12, 17, 30, 36]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 6, 11, 36]},\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [17, 23, 32]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [3, 21, 32]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [11, 33]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [12, 15, 24, 29, 44]},\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [17, 19, 23, 32]},\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [9, 13, 39, 42]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [11, 30, 22]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [10, 18, 26, 24]},\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [1, 14, 16]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [33, 47]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [20, 36]}\n    ],\n    \"complexes\": [\n      \"PRMT5:MEP50/WDR77 methylosome\"\n    ],\n    \"partners\": [\n      \"WDR77\",\n      \"CLNS1A\",\n      \"RIOK1\",\n      \"COPR5\",\n      \"EZH2\",\n      \"TBL2\",\n      \"SMAD3\",\n      \"METTL3\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}