{"gene":"PCMT1","run_date":"2026-06-10T05:19:53","timeline":{"discoveries":[{"year":2025,"finding":"PCMT1 promotes formation of C-terminal cyclic imide modifications on C-terminal asparagine residues of CRBN (cereblon) substrates, co-regulating levels of metabolic enzymes glutamine synthetase (GLUL) and inorganic pyrophosphatase 1 (PPA1) in vitro, in cells, and in vivo; this regulation is associated with the proepileptic phenotype of CRBN knockout mouse models.","method":"In vitro biochemical assays, cell-based experiments, in vivo mouse models, CRBN knockout phenotype analysis","journal":"Nature chemical biology","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro reconstitution, cell-based and in vivo validation, published in peer-reviewed journal and confirmed by preprint; multiple orthogonal methods across two publications (PMID:41461925, PMID:40196534)","pmids":["41461925","40196534"],"is_preprint":false},{"year":2025,"finding":"PCMT1 is unconventionally secreted and enzymatically interacts with the ectodomain of TGF-β receptor 2 (TGFBR2), reversing N63 deamidation (isoaspartate formation) on TGFBR2, which triggers TGFBR2 ubiquitination and degradation, thereby suppressing TGF-β1/Smad signaling and inhibiting kidney fibrosis.","method":"Immunoprecipitation, gene lentivirus overexpression/knockout, post-translational modification mass spectrometry, tubule-specific Pcmt1 knockout murine models","journal":"Journal of the American Society of Nephrology : JASN","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — IP-MS identifying PTM, KO mouse model with defined phenotype, in vitro enzymatic assay, multiple orthogonal methods in single lab","pmids":["40036072"],"is_preprint":false},{"year":2022,"finding":"PCMT1 is released extracellularly from ovarian cancer cells and interacts with the ECM protein LAMB3, which binds to integrin and activates FAK-Src signaling to promote cancer cell migration, adhesion, and metastasis.","method":"Immunoprecipitation followed by mass spectrometry (IP-MS), CRISPR/Cas9 knockout screen, western blot, live cell imaging, in vivo mouse models","journal":"Journal of experimental & clinical cancer research : CR","confidence":"High","confidence_rationale":"Tier 2 / Moderate — genome-wide CRISPR screen plus IP-MS identification of LAMB3 interaction plus in vivo validation, multiple orthogonal methods in single lab","pmids":["35033172"],"is_preprint":false},{"year":2014,"finding":"PCMT1 methylates histone H4 at aspartate 24 (H4D24me), acting as a novel histone methyltransferase involved in protein repair of isoaspartate-containing histones; the H4D24me mark is specifically recognized by VprBP (a chromo domain-containing protein), potentially implicating H4D24me in H4 degradation and histone homeostasis.","method":"In vitro methyltransferase assay, generation of H4D24me-specific antibodies, in vivo chromatin analysis in mouse and human cells","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro enzymatic assay demonstrating methyltransferase activity, antibody-based in vivo validation, identification of reader protein VprBP by binding assay","pmids":["25327473"],"is_preprint":false},{"year":2017,"finding":"PCMT1 inhibits neuronal apoptosis after subarachnoid hemorrhage by reducing MST1 phosphorylation and levels of cleaved MST1 (cl-MST1); pharmacological activation of PCMT1 with CGP 3466B reduced MST1 activity and apoptosis, while acceleration of MST1 phosphorylation (calyculin A) or increase in cl-MST1 (chelerythrine) reversed these neuroprotective effects.","method":"Rat SAH model, pharmacological agonist/antagonist administration, western blotting, immunofluorescence, intracerebroventricular drug delivery","journal":"Translational stroke research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — defined in vivo pathway (PCMT1→MST1) with pharmacological rescue experiments and quantitative apoptosis readout, single lab","pmids":["28534197"],"is_preprint":false},{"year":2020,"finding":"Protein kinase C theta (PKCθ) modulates PCMT1 expression through hnRNPL in induced regulatory T cells; PCMT1 acts as an instability factor by methylating the FOXP3 promoter, destabilizing FOXP3 expression.","method":"Cell-penetrating peptide mimic delivery of anti-PKCθ, RNA processing analysis, cell-penetrating antibody targeting PCMT1, T cell differentiation assays","journal":"Molecular therapy : the journal of the American Society of Gene Therapy","confidence":"Medium","confidence_rationale":"Tier 2-3 / Weak — defined signaling pathway (PKCθ→hnRNPL→PCMT1→FOXP3) with functional T cell readout, but mechanistic details on FOXP3 promoter methylation rely on limited methodological description in abstract","pmids":["32592691"],"is_preprint":false},{"year":2012,"finding":"Pcmt1-deficient mice accumulate isomerized aspartyl residues, have constitutively activated insulin signaling in the brain (elevated phospho-Akt, PDK1, mTOR), and show 20-30% brain enlargement leading to fatal seizures; wortmannin (PI3K inhibitor) reduced brain size toward wild-type and nearly doubled lifespan in Pcmt1-/- animals.","method":"Pcmt1 knockout mouse model, oral wortmannin administration, immunoblotting for phospho-Akt/PDK1/mTOR, brain size measurement, lifespan analysis","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 2 / Moderate — genetic KO model with pharmacological epistasis (PI3K inhibitor rescue), immunoblot confirmation of pathway activation, quantitative phenotypic readout","pmids":["23071621"],"is_preprint":false},{"year":2026,"finding":"LITAF interacts with PCMT1 and promotes ubiquitination-mediated degradation of PCMT1, thereby inhibiting COX-2-mediated arachidonic acid metabolism and enhancing sensitivity of breast cancer cells to paclitaxel.","method":"Co-immunoprecipitation (Co-IP), ubiquitination assay, western blot, in vivo nude mouse model, metabolomics","journal":"Frontiers in pharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — Co-IP showing LITAF-PCMT1 interaction with ubiquitination assay and in vivo validation, single lab, limited mechanistic detail on how PCMT1 regulates COX-2","pmids":["42051267"],"is_preprint":false},{"year":2026,"finding":"The deubiquitinating enzyme USP13 directly interacts with PCMT1 and removes polyubiquitination of PCMT1 to maintain its stability, promoting prostate cancer cell proliferation and enzalutamide resistance.","method":"Co-immunoprecipitation, ubiquitination assay, USP13 silencing in vitro and in vivo, prostate cancer cell and xenograft models","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — Co-IP establishing USP13-PCMT1 interaction, deubiquitination assay, in vivo xenograft validation, single lab","pmids":["42056074"],"is_preprint":false},{"year":2025,"finding":"Multi-omics analysis of Pcmt1 knockout mice revealed that PCMT1 substrates (isoaspartate-carrying proteins) accumulate predominantly in extracellular and membrane-related compartments; overexpressed PCMT1 interacts with proteins mainly in extracellular and membrane-related categories, indicating an extracellular repair function beyond its canonical intracellular role.","method":"isoD-proteomics, global proteomics, transcriptomics in Pcmt1 KO vs WT mice; proteomic analysis of PCMT1-overexpressing cells","journal":"Journal of proteome research","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — multi-omics approach with KO and OE models, single lab, no direct enzymatic reconstitution of extracellular activity","pmids":["40287848"],"is_preprint":false},{"year":2014,"finding":"hsa-miR-195 directly targets the PCMT1 3'UTR as validated by co-transfection of pmirGLO-PCMT1 and pEGP-miR-195 in a luciferase reporter assay, significantly decreasing PCMT1 expression.","method":"Dual luciferase reporter assay (pmirGLO-PCMT1 + pEGP-miR-195 co-transfection)","journal":"Tumour biology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct in vitro luciferase reporter validation of miR-195 targeting PCMT1 3'UTR, single lab, single method","pmids":["25119594"],"is_preprint":false},{"year":2023,"finding":"PCMT1 regulates migration, invasion, and apoptosis of prostate cancer cells by modulating the PI3K/AKT/GSK-3β signaling pathway, as demonstrated by PCMT1 overexpression and knockdown experiments in vitro and in vivo.","method":"PCMT1 overexpression and knockdown in prostate cancer cell lines, in vivo xenograft model, western blot for PI3K/AKT/GSK-3β pathway components","journal":"Aging","confidence":"Low","confidence_rationale":"Tier 3 / Weak — pathway placement based on western blot correlation after KD/OE, no direct biochemical interaction shown, single lab","pmids":["37899170"],"is_preprint":false},{"year":2023,"finding":"PCMT1 knockdown in triple-negative breast cancer MDA-MB-231 cells globally altered transcriptome profiles including 1,084 differentially expressed genes enriched in immune/inflammation and cell adhesion pathways, and 2,287 regulated alternative splicing events enriched in cell cycle pathways; 34 RNA binding protein genes were dysregulated.","method":"shRNA knockdown, RNA-seq transcriptome analysis, RT-PCR validation","journal":"PeerJ","confidence":"Low","confidence_rationale":"Tier 3 / Weak — transcriptomics after KD, no direct mechanistic pathway placement, single lab","pmids":["37953789"],"is_preprint":false}],"current_model":"PCMT1 (protein L-isoaspartate O-methyltransferase) is an S-adenosylmethionine-dependent repair enzyme that converts spontaneously formed L-isoaspartyl residues back to normal L-aspartyl residues in damaged proteins; it also promotes formation of C-terminal cyclic imide modifications on CRBN substrates (regulating metabolic enzyme stability via the CRBN E3 ligase), methylates histone H4 at Asp24 (linking histone aging to proteostasis), enzymatically reverses deamidation on the TGFBR2 ectodomain to suppress TGF-β/Smad pro-fibrotic signaling, is unconventionally secreted to interact with ECM proteins (e.g., LAMB3) and activate integrin-FAK-Src signaling, suppresses MST1-mediated neuronal apoptosis, and is regulated post-translationally by ubiquitination (promoted by LITAF; reversed by USP13) and at the mRNA level by miR-195."},"narrative":{"mechanistic_narrative":"PCMT1 is an S-adenosylmethionine-dependent methyltransferase that repairs damaged proteins by acting on spontaneously formed isoaspartyl residues, a function whose physiological importance is evident in Pcmt1-deficient mice, which accumulate isomerized aspartyl proteins, develop constitutively activated brain insulin/PI3K-Akt-mTOR signaling, brain enlargement, and fatal seizures rescued by PI3K inhibition [PMID:23071621]. Its substrate repertoire extends to chromatin, where it methylates histone H4 at Asp24 (H4D24me), a mark recognized by the chromodomain protein VprBP and linked to histone homeostasis [PMID:25327473], and to the catalysis of C-terminal cyclic imide modifications on CRBN substrates, co-regulating the metabolic enzymes GLUL and PPA1 [PMID:41461925, PMID:40196534]. Beyond its canonical intracellular role, PCMT1 is unconventionally secreted and operates extracellularly: isoaspartate-bearing substrates and PCMT1 interactors are enriched in extracellular and membrane compartments [PMID:40287848]. Secreted PCMT1 enzymatically reverses N63 deamidation on the TGFBR2 ectodomain, driving TGFBR2 ubiquitination and degradation to suppress TGF-β1/Smad signaling and kidney fibrosis [PMID:40036072], and in ovarian cancer it interacts with the ECM protein LAMB3 to activate integrin-FAK-Src signaling and promote migration and metastasis [PMID:35033172]. PCMT1 abundance is controlled post-translationally by opposing ubiquitin machinery—LITAF promotes its ubiquitin-mediated degradation [PMID:42051267] while USP13 deubiquitinates and stabilizes it [PMID:42056074]—and at the transcript level by miR-195 targeting its 3'UTR [PMID:25119594]. PCMT1 additionally suppresses MST1-mediated neuronal apoptosis after subarachnoid hemorrhage [PMID:28534197].","teleology":[{"year":2012,"claim":"Established the physiological consequence of losing isoaspartyl repair in vivo, connecting accumulated damaged proteins to aberrant insulin/PI3K signaling and a lethal neurological phenotype.","evidence":"Pcmt1 knockout mice with pharmacological PI3K-inhibitor (wortmannin) epistasis and phospho-Akt/PDK1/mTOR immunoblotting","pmids":["23071621"],"confidence":"High","gaps":["Does not identify the specific isoaspartyl substrate(s) driving insulin pathway activation","Mechanism linking protein damage to Akt/mTOR signaling not resolved"]},{"year":2014,"claim":"Extended PCMT1 substrate scope to chromatin by showing it methylates histone H4 Asp24, tying isoaspartyl repair to histone aging and a reader-based readout.","evidence":"In vitro methyltransferase assay, H4D24me-specific antibodies, and VprBP binding assay in mouse and human cells","pmids":["25327473"],"confidence":"High","gaps":["Functional consequence of H4D24me for histone degradation only implicated, not demonstrated","Genome-wide distribution of the mark not mapped"]},{"year":2014,"claim":"Identified miR-195 as a direct negative regulator of PCMT1 expression, adding a post-transcriptional control layer.","evidence":"Dual luciferase reporter assay with pmirGLO-PCMT1 and pEGP-miR-195 co-transfection","pmids":["25119594"],"confidence":"Medium","gaps":["Single-method validation without endogenous confirmation","Physiological context where miR-195 controls PCMT1 not defined"]},{"year":2017,"claim":"Placed PCMT1 in a neuroprotective pathway by showing it suppresses MST1-driven neuronal apoptosis, addressing whether the enzyme has signaling-level roles beyond repair.","evidence":"Rat subarachnoid hemorrhage model with pharmacological PCMT1 activation (CGP 3466B) and MST1 modulators, western blot and immunofluorescence","pmids":["28534197"],"confidence":"Medium","gaps":["Whether PCMT1 acts on MST1 enzymatically or indirectly is unresolved","Pharmacological agonist specificity not established"]},{"year":2020,"claim":"Linked PCMT1 to immune cell fate, positioning it downstream of PKCθ/hnRNPL as a destabilizer of FOXP3 in regulatory T cells.","evidence":"Cell-penetrating peptide/antibody delivery, RNA processing analysis, and T cell differentiation assays","pmids":["32592691"],"confidence":"Medium","gaps":["FOXP3 promoter methylation mechanism relies on limited methodological detail","Direct enzymatic activity of PCMT1 on FOXP3 promoter not biochemically shown"]},{"year":2022,"claim":"Revealed an extracellular, signaling function for secreted PCMT1 via LAMB3-integrin-FAK-Src to drive cancer cell metastasis.","evidence":"Genome-wide CRISPR knockout screen, IP-MS identification of LAMB3, live-cell imaging, and in vivo mouse models in ovarian cancer","pmids":["35033172"],"confidence":"High","gaps":["Whether enzymatic isoaspartyl repair is required for the LAMB3 interaction is unclear","Mechanism of unconventional secretion not defined"]},{"year":2023,"claim":"Associated PCMT1 with prostate cancer cell behavior through PI3K/AKT/GSK-3β signaling and with broad transcriptome/splicing remodeling in breast cancer.","evidence":"Overexpression/knockdown with xenografts and pathway western blots; shRNA knockdown with RNA-seq","pmids":["37899170","37953789"],"confidence":"Low","gaps":["Pathway placement based on correlative western blot without direct biochemical interaction","Transcriptomic changes lack defined mechanistic link to PCMT1 enzymatic activity"]},{"year":2025,"claim":"Defined a novel catalytic output—formation of C-terminal cyclic imides on CRBN substrates—connecting PCMT1 to E3-ligase-dependent control of metabolic enzyme levels.","evidence":"In vitro reconstitution, cell-based assays, and in vivo CRBN knockout mouse phenotype analysis (GLUL, PPA1)","pmids":["41461925","40196534"],"confidence":"High","gaps":["Full substrate range of cyclic imide formation not enumerated","Relationship between cyclic imide activity and canonical isoaspartyl repair unclear"]},{"year":2025,"claim":"Demonstrated that secreted PCMT1 enzymatically reverses TGFBR2 deamidation to suppress pro-fibrotic TGF-β/Smad signaling, providing a defined extracellular substrate.","evidence":"IP, PTM mass spectrometry, lentiviral overexpression/knockout, and tubule-specific Pcmt1 knockout murine kidney fibrosis models","pmids":["40036072"],"confidence":"High","gaps":["How deamidation reversal triggers TGFBR2 ubiquitination is not detailed","Generalizability to other receptor ectodomains untested"]},{"year":2025,"claim":"Mapped PCMT1 substrate and interactor compartments via multi-omics, supporting an extracellular/membrane repair function beyond the canonical intracellular role.","evidence":"isoD-proteomics, global proteomics, and transcriptomics in Pcmt1 KO vs WT mice plus overexpression cell proteomics","pmids":["40287848"],"confidence":"Medium","gaps":["No direct enzymatic reconstitution of extracellular activity","Specific extracellular substrates not individually validated"]},{"year":2026,"claim":"Established opposing ubiquitin-system control of PCMT1 stability, with LITAF promoting degradation and USP13 stabilizing the enzyme, each tied to cancer drug sensitivity.","evidence":"Co-IP, ubiquitination/deubiquitination assays, and in vivo xenograft models in breast and prostate cancer","pmids":["42051267","42056074"],"confidence":"Medium","gaps":["How PCMT1 mechanistically regulates COX-2 metabolism is not defined","Reciprocal validation and direct interaction interfaces not mapped"]},{"year":null,"claim":"How PCMT1's canonical isoaspartyl repair activity mechanistically connects to its diverse signaling outputs (TGFBR2, LAMB3, MST1, CRBN cyclic imides) and how its secretion is controlled remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["Unconventional secretion mechanism unknown","Whether each signaling role requires methyltransferase catalysis is untested","Unifying substrate determinants across compartments not defined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,1,3,6]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,1]},{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[3]}],"localization":[{"term_id":"GO:0005576","term_label":"extracellular region","supporting_discovery_ids":[1,2,9]},{"term_id":"GO:0031012","term_label":"extracellular matrix","supporting_discovery_ids":[2]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[3]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,1,6]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[1,2]},{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[3]}],"complexes":[],"partners":["TGFBR2","LAMB3","CRBN","VPRBP","MST1","LITAF","USP13","HNRNPL"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P22061","full_name":"Protein-L-isoaspartate(D-aspartate) O-methyltransferase","aliases":["L-isoaspartyl protein carboxyl methyltransferase","Protein L-isoaspartyl/D-aspartyl methyltransferase","Protein-beta-aspartate methyltransferase"],"length_aa":227,"mass_kda":24.6,"function":"Initiates the repair of damaged proteins by catalyzing methyl esterification of L-isoaspartyl and D-aspartyl residues produced by spontaneous isomerization and racemization of L-aspartyl and L-asparaginyl residues in aging peptides and proteins (PubMed:3167043, PubMed:6469980). Acts on EIF4EBP2, microtubule-associated protein 2, calreticulin, clathrin light chains a and b, Ubiquitin C-terminal hydrolase isozyme L1, phosphatidylethanolamine-binding protein 1, stathmin, beta-synuclein and alpha-synuclein (By similarity)","subcellular_location":"Cytoplasm, cytosol","url":"https://www.uniprot.org/uniprotkb/P22061/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/PCMT1","classification":"Not Classified","n_dependent_lines":8,"n_total_lines":1208,"dependency_fraction":0.006622516556291391},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/PCMT1","total_profiled":1310},"omim":[{"mim_id":"620091","title":"PROTEIN-L-ISOASPARTATE (D-ASPARTATE) O-METHYLTRANSFERASE DOMAIN-CONTAINING PROTEIN 1; PCMTD1","url":"https://www.omim.org/entry/620091"},{"mim_id":"176851","title":"PROTEIN-L-ISOASPARTATE (D-ASPARTATE) O-METHYLTRANSFERASE; PCMT1","url":"https://www.omim.org/entry/176851"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PCMT1"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"P22061","domains":[{"cath_id":"3.40.50.150","chopping":"61-217","consensus_level":"high","plddt":97.9978,"start":61,"end":217}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P22061","model_url":"https://alphafold.ebi.ac.uk/files/AF-P22061-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P22061-F1-predicted_aligned_error_v6.png","plddt_mean":96.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PCMT1","jax_strain_url":"https://www.jax.org/strain/search?query=PCMT1"},"sequence":{"accession":"P22061","fasta_url":"https://rest.uniprot.org/uniprotkb/P22061.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P22061/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P22061"}},"corpus_meta":[{"pmid":"35033172","id":"PMC_35033172","title":"Genome-wide CRISPR/Cas9 library screen 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the C-terminal cyclic imide degron on CRBN substrates.","date":"2025","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/40196534","citation_count":5,"is_preprint":false},{"pmid":"37953789","id":"PMC_37953789","title":"PCMT1 knockdown attenuates malignant properties by globally regulating transcriptome profiles in triple-negative breast cancer cells.","date":"2023","source":"PeerJ","url":"https://pubmed.ncbi.nlm.nih.gov/37953789","citation_count":5,"is_preprint":false},{"pmid":"38853025","id":"PMC_38853025","title":"Silencing PCMT1 enhances the sensitivity of breast cancer cells to paclitaxel through the PI3K/Akt/STMN1 pathway.","date":"2024","source":"Chemical biology & drug design","url":"https://pubmed.ncbi.nlm.nih.gov/38853025","citation_count":3,"is_preprint":false},{"pmid":"32705859","id":"PMC_32705859","title":"Neural stem cell conditioned medium alleviates Aβ25-35 damage to SH-SY5Y cells through the PCMT1/MST1 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EJH","url":"https://pubmed.ncbi.nlm.nih.gov/33334092","citation_count":1,"is_preprint":false},{"pmid":"42051267","id":"PMC_42051267","title":"LITAF suppresses breast cancer and paclitaxel resistance by ubiquitinating and degrading PCMT1 to inhibit COX-2-dependent arachidonic acid metabolism.","date":"2026","source":"Frontiers in pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/42051267","citation_count":0,"is_preprint":false},{"pmid":"42056074","id":"PMC_42056074","title":"USP13 promotes enzalutamide resistance by catalyzing depolyubiquitination of PCMT1 in prostate cancer.","date":"2026","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/42056074","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.07.08.663800","title":"IsoDGR-Induced Endothelial Cytoskeletal Disruption Drives Age-Related Blood-Brain Barrier Breakdown","date":"2025-07-14","source":"bioRxiv","url":"https://doi.org/10.1101/2025.07.08.663800","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.06.09.658749","title":"Anti-isoDGR Antibody Inhibits Atherosclerosis Induced by Western Diet in ApoE  <sup>-/-</sup>  mice","date":"2025-06-12","source":"bioRxiv","url":"https://doi.org/10.1101/2025.06.09.658749","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.05.21.654933","title":"Structural basis for L-isoaspartyl-containing protein recognition by the PCMTD1 cullin-RING E3 ubiquitin ligase","date":"2025-05-21","source":"bioRxiv","url":"https://doi.org/10.1101/2025.05.21.654933","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19545,"output_tokens":3427,"usd":0.05502,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10986,"output_tokens":3933,"usd":0.076628,"stage2_stop_reason":"end_turn"},"total_usd":0.131648,"stage1_batch_id":"msgbatch_013a8chtv3AWyTqv4z4sEF4C","stage2_batch_id":"msgbatch_01AHsuW63vinsvuTgzmQ3n62","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2025,\n      \"finding\": \"PCMT1 promotes formation of C-terminal cyclic imide modifications on C-terminal asparagine residues of CRBN (cereblon) substrates, co-regulating levels of metabolic enzymes glutamine synthetase (GLUL) and inorganic pyrophosphatase 1 (PPA1) in vitro, in cells, and in vivo; this regulation is associated with the proepileptic phenotype of CRBN knockout mouse models.\",\n      \"method\": \"In vitro biochemical assays, cell-based experiments, in vivo mouse models, CRBN knockout phenotype analysis\",\n      \"journal\": \"Nature chemical biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro reconstitution, cell-based and in vivo validation, published in peer-reviewed journal and confirmed by preprint; multiple orthogonal methods across two publications (PMID:41461925, PMID:40196534)\",\n      \"pmids\": [\"41461925\", \"40196534\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PCMT1 is unconventionally secreted and enzymatically interacts with the ectodomain of TGF-β receptor 2 (TGFBR2), reversing N63 deamidation (isoaspartate formation) on TGFBR2, which triggers TGFBR2 ubiquitination and degradation, thereby suppressing TGF-β1/Smad signaling and inhibiting kidney fibrosis.\",\n      \"method\": \"Immunoprecipitation, gene lentivirus overexpression/knockout, post-translational modification mass spectrometry, tubule-specific Pcmt1 knockout murine models\",\n      \"journal\": \"Journal of the American Society of Nephrology : JASN\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — IP-MS identifying PTM, KO mouse model with defined phenotype, in vitro enzymatic assay, multiple orthogonal methods in single lab\",\n      \"pmids\": [\"40036072\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PCMT1 is released extracellularly from ovarian cancer cells and interacts with the ECM protein LAMB3, which binds to integrin and activates FAK-Src signaling to promote cancer cell migration, adhesion, and metastasis.\",\n      \"method\": \"Immunoprecipitation followed by mass spectrometry (IP-MS), CRISPR/Cas9 knockout screen, western blot, live cell imaging, in vivo mouse models\",\n      \"journal\": \"Journal of experimental & clinical cancer research : CR\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genome-wide CRISPR screen plus IP-MS identification of LAMB3 interaction plus in vivo validation, multiple orthogonal methods in single lab\",\n      \"pmids\": [\"35033172\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"PCMT1 methylates histone H4 at aspartate 24 (H4D24me), acting as a novel histone methyltransferase involved in protein repair of isoaspartate-containing histones; the H4D24me mark is specifically recognized by VprBP (a chromo domain-containing protein), potentially implicating H4D24me in H4 degradation and histone homeostasis.\",\n      \"method\": \"In vitro methyltransferase assay, generation of H4D24me-specific antibodies, in vivo chromatin analysis in mouse and human cells\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro enzymatic assay demonstrating methyltransferase activity, antibody-based in vivo validation, identification of reader protein VprBP by binding assay\",\n      \"pmids\": [\"25327473\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"PCMT1 inhibits neuronal apoptosis after subarachnoid hemorrhage by reducing MST1 phosphorylation and levels of cleaved MST1 (cl-MST1); pharmacological activation of PCMT1 with CGP 3466B reduced MST1 activity and apoptosis, while acceleration of MST1 phosphorylation (calyculin A) or increase in cl-MST1 (chelerythrine) reversed these neuroprotective effects.\",\n      \"method\": \"Rat SAH model, pharmacological agonist/antagonist administration, western blotting, immunofluorescence, intracerebroventricular drug delivery\",\n      \"journal\": \"Translational stroke research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — defined in vivo pathway (PCMT1→MST1) with pharmacological rescue experiments and quantitative apoptosis readout, single lab\",\n      \"pmids\": [\"28534197\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Protein kinase C theta (PKCθ) modulates PCMT1 expression through hnRNPL in induced regulatory T cells; PCMT1 acts as an instability factor by methylating the FOXP3 promoter, destabilizing FOXP3 expression.\",\n      \"method\": \"Cell-penetrating peptide mimic delivery of anti-PKCθ, RNA processing analysis, cell-penetrating antibody targeting PCMT1, T cell differentiation assays\",\n      \"journal\": \"Molecular therapy : the journal of the American Society of Gene Therapy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Weak — defined signaling pathway (PKCθ→hnRNPL→PCMT1→FOXP3) with functional T cell readout, but mechanistic details on FOXP3 promoter methylation rely on limited methodological description in abstract\",\n      \"pmids\": [\"32592691\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Pcmt1-deficient mice accumulate isomerized aspartyl residues, have constitutively activated insulin signaling in the brain (elevated phospho-Akt, PDK1, mTOR), and show 20-30% brain enlargement leading to fatal seizures; wortmannin (PI3K inhibitor) reduced brain size toward wild-type and nearly doubled lifespan in Pcmt1-/- animals.\",\n      \"method\": \"Pcmt1 knockout mouse model, oral wortmannin administration, immunoblotting for phospho-Akt/PDK1/mTOR, brain size measurement, lifespan analysis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO model with pharmacological epistasis (PI3K inhibitor rescue), immunoblot confirmation of pathway activation, quantitative phenotypic readout\",\n      \"pmids\": [\"23071621\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"LITAF interacts with PCMT1 and promotes ubiquitination-mediated degradation of PCMT1, thereby inhibiting COX-2-mediated arachidonic acid metabolism and enhancing sensitivity of breast cancer cells to paclitaxel.\",\n      \"method\": \"Co-immunoprecipitation (Co-IP), ubiquitination assay, western blot, in vivo nude mouse model, metabolomics\",\n      \"journal\": \"Frontiers in pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — Co-IP showing LITAF-PCMT1 interaction with ubiquitination assay and in vivo validation, single lab, limited mechanistic detail on how PCMT1 regulates COX-2\",\n      \"pmids\": [\"42051267\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"The deubiquitinating enzyme USP13 directly interacts with PCMT1 and removes polyubiquitination of PCMT1 to maintain its stability, promoting prostate cancer cell proliferation and enzalutamide resistance.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, USP13 silencing in vitro and in vivo, prostate cancer cell and xenograft models\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — Co-IP establishing USP13-PCMT1 interaction, deubiquitination assay, in vivo xenograft validation, single lab\",\n      \"pmids\": [\"42056074\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Multi-omics analysis of Pcmt1 knockout mice revealed that PCMT1 substrates (isoaspartate-carrying proteins) accumulate predominantly in extracellular and membrane-related compartments; overexpressed PCMT1 interacts with proteins mainly in extracellular and membrane-related categories, indicating an extracellular repair function beyond its canonical intracellular role.\",\n      \"method\": \"isoD-proteomics, global proteomics, transcriptomics in Pcmt1 KO vs WT mice; proteomic analysis of PCMT1-overexpressing cells\",\n      \"journal\": \"Journal of proteome research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — multi-omics approach with KO and OE models, single lab, no direct enzymatic reconstitution of extracellular activity\",\n      \"pmids\": [\"40287848\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"hsa-miR-195 directly targets the PCMT1 3'UTR as validated by co-transfection of pmirGLO-PCMT1 and pEGP-miR-195 in a luciferase reporter assay, significantly decreasing PCMT1 expression.\",\n      \"method\": \"Dual luciferase reporter assay (pmirGLO-PCMT1 + pEGP-miR-195 co-transfection)\",\n      \"journal\": \"Tumour biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct in vitro luciferase reporter validation of miR-195 targeting PCMT1 3'UTR, single lab, single method\",\n      \"pmids\": [\"25119594\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PCMT1 regulates migration, invasion, and apoptosis of prostate cancer cells by modulating the PI3K/AKT/GSK-3β signaling pathway, as demonstrated by PCMT1 overexpression and knockdown experiments in vitro and in vivo.\",\n      \"method\": \"PCMT1 overexpression and knockdown in prostate cancer cell lines, in vivo xenograft model, western blot for PI3K/AKT/GSK-3β pathway components\",\n      \"journal\": \"Aging\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — pathway placement based on western blot correlation after KD/OE, no direct biochemical interaction shown, single lab\",\n      \"pmids\": [\"37899170\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PCMT1 knockdown in triple-negative breast cancer MDA-MB-231 cells globally altered transcriptome profiles including 1,084 differentially expressed genes enriched in immune/inflammation and cell adhesion pathways, and 2,287 regulated alternative splicing events enriched in cell cycle pathways; 34 RNA binding protein genes were dysregulated.\",\n      \"method\": \"shRNA knockdown, RNA-seq transcriptome analysis, RT-PCR validation\",\n      \"journal\": \"PeerJ\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — transcriptomics after KD, no direct mechanistic pathway placement, single lab\",\n      \"pmids\": [\"37953789\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PCMT1 (protein L-isoaspartate O-methyltransferase) is an S-adenosylmethionine-dependent repair enzyme that converts spontaneously formed L-isoaspartyl residues back to normal L-aspartyl residues in damaged proteins; it also promotes formation of C-terminal cyclic imide modifications on CRBN substrates (regulating metabolic enzyme stability via the CRBN E3 ligase), methylates histone H4 at Asp24 (linking histone aging to proteostasis), enzymatically reverses deamidation on the TGFBR2 ectodomain to suppress TGF-β/Smad pro-fibrotic signaling, is unconventionally secreted to interact with ECM proteins (e.g., LAMB3) and activate integrin-FAK-Src signaling, suppresses MST1-mediated neuronal apoptosis, and is regulated post-translationally by ubiquitination (promoted by LITAF; reversed by USP13) and at the mRNA level by miR-195.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PCMT1 is an S-adenosylmethionine-dependent methyltransferase that repairs damaged proteins by acting on spontaneously formed isoaspartyl residues, a function whose physiological importance is evident in Pcmt1-deficient mice, which accumulate isomerized aspartyl proteins, develop constitutively activated brain insulin/PI3K-Akt-mTOR signaling, brain enlargement, and fatal seizures rescued by PI3K inhibition [#6]. Its substrate repertoire extends to chromatin, where it methylates histone H4 at Asp24 (H4D24me), a mark recognized by the chromodomain protein VprBP and linked to histone homeostasis [#3], and to the catalysis of C-terminal cyclic imide modifications on CRBN substrates, co-regulating the metabolic enzymes GLUL and PPA1 [#0]. Beyond its canonical intracellular role, PCMT1 is unconventionally secreted and operates extracellularly: isoaspartate-bearing substrates and PCMT1 interactors are enriched in extracellular and membrane compartments [#9]. Secreted PCMT1 enzymatically reverses N63 deamidation on the TGFBR2 ectodomain, driving TGFBR2 ubiquitination and degradation to suppress TGF-\\u03b21/Smad signaling and kidney fibrosis [#1], and in ovarian cancer it interacts with the ECM protein LAMB3 to activate integrin-FAK-Src signaling and promote migration and metastasis [#2]. PCMT1 abundance is controlled post-translationally by opposing ubiquitin machinery\\u2014LITAF promotes its ubiquitin-mediated degradation [#7] while USP13 deubiquitinates and stabilizes it [#8]\\u2014and at the transcript level by miR-195 targeting its 3'UTR [#10]. PCMT1 additionally suppresses MST1-mediated neuronal apoptosis after subarachnoid hemorrhage [#4].\",\n  \"teleology\": [\n    {\n      \"year\": 2012,\n      \"claim\": \"Established the physiological consequence of losing isoaspartyl repair in vivo, connecting accumulated damaged proteins to aberrant insulin/PI3K signaling and a lethal neurological phenotype.\",\n      \"evidence\": \"Pcmt1 knockout mice with pharmacological PI3K-inhibitor (wortmannin) epistasis and phospho-Akt/PDK1/mTOR immunoblotting\",\n      \"pmids\": [\"23071621\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not identify the specific isoaspartyl substrate(s) driving insulin pathway activation\", \"Mechanism linking protein damage to Akt/mTOR signaling not resolved\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Extended PCMT1 substrate scope to chromatin by showing it methylates histone H4 Asp24, tying isoaspartyl repair to histone aging and a reader-based readout.\",\n      \"evidence\": \"In vitro methyltransferase assay, H4D24me-specific antibodies, and VprBP binding assay in mouse and human cells\",\n      \"pmids\": [\"25327473\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of H4D24me for histone degradation only implicated, not demonstrated\", \"Genome-wide distribution of the mark not mapped\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Identified miR-195 as a direct negative regulator of PCMT1 expression, adding a post-transcriptional control layer.\",\n      \"evidence\": \"Dual luciferase reporter assay with pmirGLO-PCMT1 and pEGP-miR-195 co-transfection\",\n      \"pmids\": [\"25119594\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-method validation without endogenous confirmation\", \"Physiological context where miR-195 controls PCMT1 not defined\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Placed PCMT1 in a neuroprotective pathway by showing it suppresses MST1-driven neuronal apoptosis, addressing whether the enzyme has signaling-level roles beyond repair.\",\n      \"evidence\": \"Rat subarachnoid hemorrhage model with pharmacological PCMT1 activation (CGP 3466B) and MST1 modulators, western blot and immunofluorescence\",\n      \"pmids\": [\"28534197\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether PCMT1 acts on MST1 enzymatically or indirectly is unresolved\", \"Pharmacological agonist specificity not established\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Linked PCMT1 to immune cell fate, positioning it downstream of PKC\\u03b8/hnRNPL as a destabilizer of FOXP3 in regulatory T cells.\",\n      \"evidence\": \"Cell-penetrating peptide/antibody delivery, RNA processing analysis, and T cell differentiation assays\",\n      \"pmids\": [\"32592691\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"FOXP3 promoter methylation mechanism relies on limited methodological detail\", \"Direct enzymatic activity of PCMT1 on FOXP3 promoter not biochemically shown\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Revealed an extracellular, signaling function for secreted PCMT1 via LAMB3-integrin-FAK-Src to drive cancer cell metastasis.\",\n      \"evidence\": \"Genome-wide CRISPR knockout screen, IP-MS identification of LAMB3, live-cell imaging, and in vivo mouse models in ovarian cancer\",\n      \"pmids\": [\"35033172\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether enzymatic isoaspartyl repair is required for the LAMB3 interaction is unclear\", \"Mechanism of unconventional secretion not defined\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Associated PCMT1 with prostate cancer cell behavior through PI3K/AKT/GSK-3\\u03b2 signaling and with broad transcriptome/splicing remodeling in breast cancer.\",\n      \"evidence\": \"Overexpression/knockdown with xenografts and pathway western blots; shRNA knockdown with RNA-seq\",\n      \"pmids\": [\"37899170\", \"37953789\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Pathway placement based on correlative western blot without direct biochemical interaction\", \"Transcriptomic changes lack defined mechanistic link to PCMT1 enzymatic activity\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Defined a novel catalytic output\\u2014formation of C-terminal cyclic imides on CRBN substrates\\u2014connecting PCMT1 to E3-ligase-dependent control of metabolic enzyme levels.\",\n      \"evidence\": \"In vitro reconstitution, cell-based assays, and in vivo CRBN knockout mouse phenotype analysis (GLUL, PPA1)\",\n      \"pmids\": [\"41461925\", \"40196534\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full substrate range of cyclic imide formation not enumerated\", \"Relationship between cyclic imide activity and canonical isoaspartyl repair unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Demonstrated that secreted PCMT1 enzymatically reverses TGFBR2 deamidation to suppress pro-fibrotic TGF-\\u03b2/Smad signaling, providing a defined extracellular substrate.\",\n      \"evidence\": \"IP, PTM mass spectrometry, lentiviral overexpression/knockout, and tubule-specific Pcmt1 knockout murine kidney fibrosis models\",\n      \"pmids\": [\"40036072\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How deamidation reversal triggers TGFBR2 ubiquitination is not detailed\", \"Generalizability to other receptor ectodomains untested\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Mapped PCMT1 substrate and interactor compartments via multi-omics, supporting an extracellular/membrane repair function beyond the canonical intracellular role.\",\n      \"evidence\": \"isoD-proteomics, global proteomics, and transcriptomics in Pcmt1 KO vs WT mice plus overexpression cell proteomics\",\n      \"pmids\": [\"40287848\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct enzymatic reconstitution of extracellular activity\", \"Specific extracellular substrates not individually validated\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Established opposing ubiquitin-system control of PCMT1 stability, with LITAF promoting degradation and USP13 stabilizing the enzyme, each tied to cancer drug sensitivity.\",\n      \"evidence\": \"Co-IP, ubiquitination/deubiquitination assays, and in vivo xenograft models in breast and prostate cancer\",\n      \"pmids\": [\"42051267\", \"42056074\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How PCMT1 mechanistically regulates COX-2 metabolism is not defined\", \"Reciprocal validation and direct interaction interfaces not mapped\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How PCMT1's canonical isoaspartyl repair activity mechanistically connects to its diverse signaling outputs (TGFBR2, LAMB3, MST1, CRBN cyclic imides) and how its secretion is controlled remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Unconventional secretion mechanism unknown\", \"Whether each signaling role requires methyltransferase catalysis is untested\", \"Unifying substrate determinants across compartments not defined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 1, 3, 6]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005576\", \"supporting_discovery_ids\": [1, 2, 9]},\n      {\"term_id\": \"GO:0031012\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 1, 6]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [1, 2]},\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TGFBR2\", \"LAMB3\", \"CRBN\", \"VprBP\", \"MST1\", \"LITAF\", \"USP13\", \"hnRNPL\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}