{"gene":"PHF2","run_date":"2026-06-10T06:43:35","timeline":{"discoveries":[{"year":2011,"finding":"PHF2 is enzymatically inactive as a H3K9me2 demethylase by itself but is activated by PKA-mediated phosphorylation; phosphorylated PHF2 then associates with the DNA-binding protein ARID5B, induces demethylation of methylated ARID5B, and the resulting complex targets gene promoters to remove repressive H3K9Me2 marks.","method":"Biochemical assays, co-immunoprecipitation, in vitro phosphorylation, ChIP, and cell-based demethylase activity assays","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — multiple orthogonal methods (biochemical demethylase assay, Co-IP, ChIP) in a focused mechanistic study; widely cited and consistent with structural work","pmids":["21532585"],"is_preprint":false},{"year":2010,"finding":"The PHD finger of PHF2 recognizes histone H3K4 trimethylation, and this interaction is essential for PHF2 occupancy and H3K9 demethylation at rDNA promoters, demonstrating cross-talk between H3K4me3 reading and H3K9 demethylase activity.","method":"Biochemical binding assays, X-ray crystallography, and ChIP","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structure of PHD–H3K4me3 interaction combined with functional ChIP validation in a single focused study","pmids":["20129925"],"is_preprint":false},{"year":2010,"finding":"The PHF2 Jumonji domain coordinates Fe2+ or Ni2+ via H249, D251, N-oxalylglycine (α-ketoglutarate analog), Y321, and one water molecule in an octahedral arrangement; a Y321H mutation (replacing the atypical tyrosine fifth ligand with histidine) does not restore demethylase activity on histone peptides in vitro, indicating additional regulatory factors are required for enzymatic activity.","method":"X-ray crystallography (crystal structures in absence and presence of metal ions), in vitro demethylase activity assay, site-directed mutagenesis (Y321H), metal binding affinity measurement","journal":"Journal of molecular biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structures plus mutagenesis plus in vitro activity assay in one focused study","pmids":["21167174"],"is_preprint":false},{"year":2013,"finding":"ARID5B physically associates with Sox9 and recruits PHF2 to Sox9 target gene promoters, stimulating H3K9me2 demethylation; loss of Arid5b in mice and cells increases H3K9me2 at chondrogenic gene promoters and impairs chondrogenesis, and PHF2 knockdown inhibits Sox9-induced chondrocyte differentiation.","method":"Co-immunoprecipitation, ChIP, mouse knockout model (Arid5b−/−), siRNA knockdown, differentiation assays","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, ChIP, in vivo KO and in vitro KD with defined phenotypic readouts, multiple orthogonal methods","pmids":["24276541"],"is_preprint":false},{"year":2014,"finding":"PHF2 physically associates with p53 and promotes p53-driven transcription of downstream targets (e.g., p21) by demethylating the repressive H3K9me2 mark at target promoters; PHF2 depletion abolishes p21 induction by oxaliplatin/doxorubicin despite strong p53 induction in xenograft models.","method":"Co-immunoprecipitation, ChIP, siRNA knockdown, xenograft tumor model, Western blotting","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, ChIP, and in vivo xenograft with defined mechanistic outcome","pmids":["25043306"],"is_preprint":false},{"year":2014,"finding":"PHF2 inhibits rDNA transcription by competing with the activating demethylase PHF8 for binding to rDNA promoters (through H3K4me2/3 recognition via its PHD) and by recruiting the H3K9me2/3 methyltransferase SUV39H1; demethylase activity of PHF2 is not required for this repressive function.","method":"RNAi knockdown, overexpression, ChIP, RNA polymerase I transcription assays, co-immunoprecipitation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (Co-IP, ChIP, transcription assays) with domain-function dissection (PHD vs. catalytic mutants) in one focused study","pmids":["25204660"],"is_preprint":false},{"year":2014,"finding":"PHF2 physically interacts with the adipogenic transcription factors C/EBPα and C/EBPδ, binds their target gene promoters, and demethylates H3K9me2 there to activate adipogenic gene expression; PHF2 knockdown reduces lipid accumulation and metabolic gene expression during adipocyte differentiation.","method":"Co-immunoprecipitation, ChIP, stable shRNA knockdown in 3T3-L1 cells, cDNA microarray, qRT-PCR, Western blotting","journal":"Molecules and cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP and ChIP with functional KD phenotype in a single lab study","pmids":["25266703"],"is_preprint":false},{"year":2018,"finding":"PHF2 functions as a transcriptional co-activator of ChREBP by erasing H3K9me2 marks at ChREBP-regulated gene promoters in hepatocytes, facilitating lipogenesis; PHF2 also activates Nrf2 target genes, redirecting glucose toward the pentose phosphate pathway and protecting from oxidative stress in diet-induced obesity.","method":"ChIP, mouse genetic models, siRNA knockdown, metabolic flux analyses, lipidomics","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP linking H3K9me2 removal to specific promoters, validated in vivo mouse models plus in vitro mechanistic assays across multiple orthogonal methods","pmids":["29844386"],"is_preprint":false},{"year":2018,"finding":"PHF2 binds the p53 promoter, demethylates H3K9me2 in that region, and thereby regulates p53 expression; during megakaryocytic and erythroid differentiation, PHF2 downregulation parallels p53 downregulation and knockdown of PHF2 promotes differentiation.","method":"ChIP, co-immunoprecipitation, siRNA knockdown, Western blotting, differentiation assays in K562 and CD34+ cells","journal":"Journal of cellular physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP and KD with defined readout but single lab study","pmids":["29336484"],"is_preprint":false},{"year":2019,"finding":"PHF2 controls expression of DNA replication and cell cycle progression genes in neural progenitors by maintaining low H3K9me3 levels at their promoters; PHF2 depletion causes R-loop accumulation, DNA damage, and cell cycle arrest, revealing PHF2 as a guardian of genome stability in neural development.","method":"siRNA knockdown in neural progenitors, genome-wide ChIP-seq, R-loop detection (S9.6 immunostaining), DNA damage assays (γH2AX), cell cycle analysis, in vivo chicken spinal cord electroporation","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — genome-wide ChIP-seq plus functional KD with multiple orthogonal readouts (R-loops, DNA damage, cell cycle) and in vivo validation","pmids":["31488723"],"is_preprint":false},{"year":2019,"finding":"PHF2 promotes long-term memory consolidation by epigenetically reinforcing the TrkB-CREB signaling pathway; PHF2 knockdown in mouse hippocampus impairs memory formation while PHF2 transgenic overexpression enhances it, and PHF2 elevates field EPSP and NMDA receptor-mediated EPSC in CA1 neurons.","method":"Lentiviral shRNA knockdown in hippocampus, transgenic overexpression, behavioral tests (fear conditioning), electrophysiology (LTP recordings), ChIP","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 2 / Moderate — in vivo genetic manipulation with electrophysiology and behavioral readouts plus ChIP, multiple orthogonal methods in one study","pmids":["31359606"],"is_preprint":false},{"year":2020,"finding":"PHF2 promotes DNA repair by homologous recombination by controlling CtIP-dependent resection of DNA double-strand breaks; PHF2 knockdown decreases CtIP and BRCA1 protein and mRNA levels (dependent on PHF2 demethylase activity), impairs BRCA1 and RPA focus formation, delays 53BP1 foci resolution, and reduces Rad51 focus formation and HDR efficiency.","method":"siRNA knockdown, immunofluorescence (IRIF foci), HR reporter assay, RPA phosphorylation assays, qRT-PCR, Western blotting, sensitivity assays (PARPi)","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal functional readouts (focus formation, HR assay, demethylase-dead mutant) in one focused study","pmids":["32232336"],"is_preprint":false},{"year":2022,"finding":"The PHF2 PHD and Jumonji domains together form a complete methyl-lysine binding aromatic cage at their interface: H3K4me3 (and VRK1 K4me3) peptides bind across both domains with affinities (KD ~160 nM for H3, ~42 nM for VRK1) 4–21× higher than for the isolated PHD alone; crystal structures show R2 of the peptide engaging acidic residues on both domains and K4me3 encircled by aromatic residues from both domains.","method":"X-ray crystallography, fluorescence polarization binding assays, peptide binding studies","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structures with quantitative binding measurements identifying structural basis of bivalent recognition","pmids":["36596360"],"is_preprint":false},{"year":2023,"finding":"PHF2 functions as an E3 ubiquitin ligase that directly ubiquitinates and destabilizes SREBP1c, thereby suppressing SREBP1c-dependent lipogenesis in hepatocellular carcinoma; the palmitoyltransferase ZDHHC23 palmitoylates PHF2, enhancing its ubiquitin-dependent proteasomal degradation, which relieves SREBP1c suppression and promotes lipid reprogramming.","method":"Co-immunoprecipitation, ubiquitination assays, palmitoylation assays, protein stability assays, siRNA knockdown, overexpression in HepG2 and Hep3B cells","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — in vitro ubiquitination and palmitoylation assays, Co-IP, and functional protein stability measurements with defined substrates","pmids":["37828054"],"is_preprint":false},{"year":2023,"finding":"AMPKα2 directly phosphorylates PHF2 at Ser655, enhancing PHF2 demethylase activity toward H3K9me2 and promoting transcription of epithelial genes (e.g., CDH1); a phospho-mimetic PHF2-S655E mutant reduces H3K9me2 and suppresses lung cancer metastasis, while S655A mutant reverses the anti-metastatic effect of metformin.","method":"In vitro kinase assay, co-immunoprecipitation (PHF2–AMPKα2), site-directed mutagenesis (S655E and S655A), H3K9me2 ChIP, loss-of-function (PHF2 KO), cell migration/invasion assays, mouse metastasis model","journal":"Signal transduction and targeted therapy","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vitro kinase assay plus mutagenesis plus ChIP plus in vivo metastasis model with multiple orthogonal methods","pmids":["36872368"],"is_preprint":false},{"year":2024,"finding":"PHF2 associates with RAD21, a core cohesin subunit, to regulate DNA replication in mouse neural stem cells; PHF2/RAD21 co-bound genomic regions resemble active replication origins; PHF2 loss weakens TAD boundaries and chromatin loops at co-bound loci due to reduced RAD21 occupancy and activates dormant replication origins; notably, PHF2's histone demethylase activity is dispensable for this function.","method":"Co-immunoprecipitation, ChIP-seq, Hi-C (genome topology), DNA replication origin mapping, CRISPR/Cas9 PHF2 KO in mouse NSC, catalytic-dead mutant rescue","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — Co-IP, genome-wide ChIP-seq, Hi-C, and KO with mechanistic rescue using catalytic-dead mutant in one focused study","pmids":["38808662"],"is_preprint":false},{"year":2024,"finding":"PHF2 interacts with heterochromatin components and localizes to pericentromeric heterochromatin (PcH) boundaries where it maintains transcriptional activity essential for silencing satellite repeats; PHF2 depletion increases heterochromatic repeat transcription, decreases H3K9me3 levels, and disrupts PcH organization, causing DNA damage; both the PHD and catalytic Jumonji domains are required for PcH stability.","method":"Mass spectrometry (Co-IP interactome), ChIP-seq, RNA-seq, immunofluorescence, CRISPR/Cas9 KO, domain-deletion mutants","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 2 / Moderate — mass spectrometry Co-IP, genome-wide ChIP-seq, RNA-seq, and domain dissection in one focused study","pmids":["38890452"],"is_preprint":false},{"year":2024,"finding":"PHF2 binds to promoter regions of sarcomeric genes (e.g., Mybpc2, Mef2c, Myh7) and demethylates H3K9me2 there; PHF2 KO in C2C12 myoblasts by CRISPR/Cas9 severely reduces sarcomeric gene expression and increases H3K9me2 at those loci during differentiation.","method":"CRISPR/Cas9 knockout, RNA-seq, ChIP (H3K9me2), qRT-PCR, Western blotting, differentiation assays","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR KO with RNA-seq and ChIP validation, single lab study","pmids":["38701072"],"is_preprint":false},{"year":2025,"finding":"Cohesin translocates PHF2 through the genome via DNA loop extrusion; PHF2 binds H3K4me3 nucleosomes at active TSSs and also co-localizes with cohesin; cohesin depletion reduces PHF2 binding at sites lacking H3K4me3; conversely, PHF2 depletion reduces cohesin binding at TSSs lacking CTCF and decreases short cohesin loops while increasing heterochromatic B compartment size.","method":"ChIP-seq, co-immunoprecipitation, conditional cohesin depletion (auxin-inducible degron), Wapl/CTCF depletion, Hi-C","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal genome-wide approaches (ChIP-seq, Hi-C) combined with reciprocal depletion experiments establishing bidirectional functional relationship","pmids":["39748119"],"is_preprint":false},{"year":2025,"finding":"PHF2 promotes lipid droplet homeostasis in muscle stem cells (MuSCs) during regenerative myogenesis by facilitating contacts between lipid droplets and mitochondria; PHF2 loss causes lipid droplet accumulation, mitochondrial dysfunction, and impaired regeneration; expression of an AMPKα2-phospho-mimetic PHF2 mutant rescues the phenotype, placing PHF2 downstream of AMPKα2 in this pathway.","method":"Mouse muscle regeneration model, CRISPR/Cas9 PHF2 KO, phospho-mimetic mutant rescue, live-cell imaging of lipid droplet–mitochondria contacts, functional regeneration assays","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo KO with mechanistic rescue by phospho-mimetic mutant; preprint, not yet peer-reviewed","pmids":["bio_10.1101_2025.01.18.630727"],"is_preprint":true},{"year":2026,"finding":"PHF2 binds to TSS-downstream regions of Mef2c and other muscle-function genes in fast-twitch muscle fibers and demethylates H3K9me2 there; skeletal muscle-specific PHF2 knockout mice show significantly reduced grip strength with preferential effects in fast-twitch muscles.","method":"Skeletal muscle-specific Phf2 KO mice, ChIP-seq, grip strength measurements, fiber-type-specific phenotyping","journal":"iScience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — tissue-specific KO in vivo with ChIP-seq, single lab study","pmids":["42006298"],"is_preprint":false},{"year":2025,"finding":"PHF2 (KDM7C) regulates inflammatory gene expression in Alzheimer's disease contexts: ChIP-seq combined with bidirectional Phf2 manipulation shows PHF2 controls Stat3, Nfkbia, Nfkb2, Tnfrsf1a, and other neuroinflammation genes; Phf2 knockdown in 5xFAD mice reduces microglial/astrocyte activation and restores glutamatergic synaptic function.","method":"ChIP-seq, siRNA knockdown in 5xFAD mice, qRT-PCR, immunohistochemistry, electrophysiology, behavioral testing (Barnes maze)","journal":"Molecular psychiatry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-seq plus in vivo KD with multiple readouts (electrophysiology, behavior, histology), single lab study","pmids":["40849543"],"is_preprint":false}],"current_model":"PHF2 is a Jumonji-C domain H3K9me2 demethylase whose catalytic activity requires regulatory phosphorylation (by PKA at an unspecified site or by AMPK at S655) and whose PHD finger binds H3K4me3 to co-localize the enzyme with active promoters; it operates in complex with DNA-binding partners (ARID5B, C/EBPα/δ, ChREBP, p53, Sox9 via Arid5b) to selectively erase repressive H3K9me2 at target gene promoters, and additionally functions as an E3 ubiquitin ligase for SREBP1c, recruits SUV39H1 to repress rDNA transcription, interacts with cohesin (RAD21) to organize TAD boundaries and regulate DNA replication origins, and maintains pericentromeric heterochromatin stability—with its demethylase activity being dispensable for the cohesin-related topological functions."},"narrative":{"mechanistic_narrative":"PHF2 is a Jumonji-C family histone demethylase that erases the repressive H3K9me2 mark at target gene promoters to activate transcription across diverse developmental and metabolic programs [PMID:21532585, PMID:29844386]. Its catalytic Jumonji domain coordinates Fe2+ and α-ketoglutarate in an octahedral arrangement, but the isolated enzyme is intrinsically inactive on histone substrates and requires regulatory input — PKA-mediated phosphorylation licenses demethylation and assembly with the DNA-binding partner ARID5B [PMID:21532585, PMID:21167174], while AMPKα2 phosphorylation at Ser655 enhances H3K9me2 demethylase activity [PMID:36872368]. Promoter targeting is achieved through a bivalent reader module in which the PHD finger and Jumonji domain together form a methyl-lysine aromatic cage that binds H3K4me3 with high affinity, coupling recognition of active chromatin to H3K9 demethylation [PMID:20129925, PMID:36596360]. PHF2 is recruited to specific loci by sequence-specific transcription factors — ARID5B (including ARID5B–Sox9 complexes), C/EBPα/δ, ChREBP, and p53 — to selectively activate chondrogenic, adipogenic, lipogenic, and p53-target genes [PMID:24276541, PMID:25043306, PMID:25266703, PMID:29844386]. Beyond gene activation, PHF2 has repressive and structural functions that are independent of its demethylase activity: it competes with PHF8 and recruits the methyltransferase SUV39H1 to silence rDNA transcription [PMID:25204660], and it associates with the cohesin subunit RAD21 to organize TAD boundaries, chromatin loops, and DNA replication origins, with cohesin loop extrusion translocating PHF2 across the genome [PMID:38808662, PMID:39748119]. PHF2 functions as a guardian of genome stability, maintaining pericentromeric heterochromatin integrity, suppressing R-loop accumulation and DNA damage, and promoting CtIP/BRCA1-dependent homologous recombination repair [PMID:31488723, PMID:32232336, PMID:38890452]. PHF2 additionally acts as an E3 ubiquitin ligase that ubiquitinates and destabilizes SREBP1c to restrain lipogenesis [PMID:37828054]. Through these activities it controls neural progenitor proliferation, memory consolidation, myogenic and metabolic differentiation, and tumor and neuroinflammatory phenotypes [PMID:31488723, PMID:31359606, PMID:36872368, PMID:38701072, PMID:40849543].","teleology":[{"year":2010,"claim":"Established how PHF2 is targeted to chromatin and linked H3K4me3 reading to H3K9 demethylase output, defining the basic reader–eraser cross-talk.","evidence":"X-ray crystallography of the PHD–H3K4me3 interaction with ChIP validation at rDNA promoters","pmids":["20129925"],"confidence":"High","gaps":["Did not resolve why the isolated enzyme lacks robust catalytic activity","Promoter selectivity beyond rDNA not addressed"]},{"year":2010,"claim":"Defined the catalytic Jumonji active-site architecture and revealed that an atypical fifth metal ligand alone does not account for the enzyme's inactivity, predicting a requirement for additional regulatory factors.","evidence":"Crystal structures with/without metal, in vitro demethylase assay, and Y321H mutagenesis","pmids":["21167174"],"confidence":"High","gaps":["The activating factor/modification was not identified in this study","No histone substrate turnover demonstrated in vitro"]},{"year":2011,"claim":"Resolved the activation paradox by showing PHF2 is inactive alone and requires PKA phosphorylation plus ARID5B partnership to demethylate target promoters.","evidence":"In vitro phosphorylation, Co-IP, ChIP, and cell-based demethylase assays","pmids":["21532585"],"confidence":"High","gaps":["The specific PKA phosphosite was not defined","Mechanism by which phosphorylation activates catalysis unresolved"]},{"year":2013,"claim":"Showed PHF2 is recruited by transcription-factor complexes (ARID5B–Sox9) to drive a defined developmental program, establishing partner-directed promoter targeting in vivo.","evidence":"Reciprocal Co-IP, ChIP, Arid5b knockout mice, siRNA, and chondrocyte differentiation assays","pmids":["24276541"],"confidence":"High","gaps":["Whether PHF2 phosphorylation status governs Sox9-target activation not tested"]},{"year":2014,"claim":"Extended partner-directed activation to multiple transcription factors (p53, C/EBPα/δ) and showed PHF2 is required for their downstream transcriptional output and phenotypes.","evidence":"Co-IP, ChIP, siRNA/shRNA knockdown, xenograft and adipocyte differentiation models","pmids":["25043306","25266703"],"confidence":"High","gaps":["Adipogenic role rests on a single-lab Medium-confidence study","Direct vs indirect promoter binding not fully separated"]},{"year":2014,"claim":"Revealed a demethylase-independent repressive function, showing PHF2 can silence rDNA by competing with PHF8 and recruiting SUV39H1.","evidence":"RNAi, overexpression, ChIP, Pol I transcription assays, Co-IP, and catalytic-mutant dissection","pmids":["25204660"],"confidence":"High","gaps":["How PHF2 toggles between activating and repressive modes at different loci is unresolved"]},{"year":2018,"claim":"Connected PHF2 demethylase activity to systemic lipid and oxidative-stress metabolism through ChREBP co-activation and Nrf2 target regulation.","evidence":"ChIP, mouse genetic models, siRNA, metabolic flux and lipidomic analyses","pmids":["29844386"],"confidence":"High","gaps":["Upstream signal coupling metabolic state to PHF2 activity not defined here"]},{"year":2019,"claim":"Identified PHF2 as a genome-stability factor in neural progenitors that keeps replication/cell-cycle genes accessible and prevents R-loop-associated DNA damage.","evidence":"siRNA, genome-wide ChIP-seq, S9.6 R-loop staining, γH2AX, cell-cycle analysis, in vivo electroporation","pmids":["31488723"],"confidence":"High","gaps":["Whether genome instability is a direct demethylase effect or secondary to transcriptional defects not fully separated"]},{"year":2020,"claim":"Showed PHF2 promotes homologous recombination repair by demethylase-dependent control of CtIP/BRCA1 expression and DSB resection.","evidence":"siRNA, IRIF immunofluorescence, HR reporter assay, RPA phosphorylation, PARPi sensitivity","pmids":["32232336"],"confidence":"High","gaps":["Direct chromatin recruitment to break sites not demonstrated"]},{"year":2022,"claim":"Defined the structural basis of high-affinity methyl-lysine reading, showing PHD and Jumonji domains form a single bivalent aromatic cage rather than the PHD acting alone.","evidence":"X-ray crystallography and fluorescence polarization binding with H3 and VRK1 peptides","pmids":["36596360"],"confidence":"High","gaps":["Functional consequence of VRK1-K4me3 binding not established","How bivalent reading couples to catalysis unresolved"]},{"year":2023,"claim":"Uncovered a non-demethylase enzymatic activity, defining PHF2 as an E3 ubiquitin ligase for SREBP1c that is itself regulated by ZDHHC23 palmitoylation-driven degradation.","evidence":"Co-IP, in vitro ubiquitination and palmitoylation assays, protein stability assays in hepatoma cells","pmids":["37828054"],"confidence":"High","gaps":["Catalytic residues mediating ligase activity not mapped","Generality of E3 activity beyond SREBP1c unknown"]},{"year":2023,"claim":"Identified AMPKα2 phosphorylation at Ser655 as a defined activating modification that boosts H3K9me2 demethylation and suppresses metastasis, providing a kinase-to-chromatin axis.","evidence":"In vitro kinase assay, Co-IP, S655E/S655A mutagenesis, ChIP, and mouse metastasis model","pmids":["36872368"],"confidence":"High","gaps":["Relationship between the AMPK Ser655 and earlier PKA phosphorylation events not reconciled"]},{"year":2024,"claim":"Established demethylase-independent structural roles, showing PHF2 partners with cohesin/RAD21 to set TAD boundaries, loops, and replication origins.","evidence":"Co-IP, ChIP-seq, Hi-C, replication origin mapping, CRISPR KO with catalytic-dead rescue in neural stem cells","pmids":["38808662"],"confidence":"High","gaps":["Direct physical contact interface between PHF2 and cohesin not mapped"]},{"year":2024,"claim":"Showed PHF2 maintains pericentromeric heterochromatin and satellite silencing requiring both PHD and Jumonji domains, linking it to genome integrity at repeats.","evidence":"Mass-spec interactome, ChIP-seq, RNA-seq, immunofluorescence, CRISPR KO, domain-deletion mutants","pmids":["38890452"],"confidence":"High","gaps":["How an H3K9me2 demethylase sustains H3K9me3-rich heterochromatin mechanistically unclear"]},{"year":2025,"claim":"Demonstrated that cohesin loop extrusion actively translocates PHF2 genome-wide and that the relationship is reciprocal, with PHF2 stabilizing cohesin at CTCF-independent TSSs.","evidence":"ChIP-seq, Co-IP, auxin-inducible cohesin/Wapl/CTCF depletion, and Hi-C","pmids":["39748119"],"confidence":"High","gaps":["Molecular basis of PHF2 hand-off to cohesin not defined"]},{"year":2025,"claim":"Extended the AMPK–PHF2 axis to muscle stem cell metabolism, linking PHF2 to lipid droplet–mitochondria contacts and regeneration.","evidence":"Mouse regeneration model, CRISPR KO, phospho-mimetic rescue, live-cell organelle-contact imaging (preprint)","pmids":["bio_10.1101_2025.01.18.630727"],"confidence":"Medium","gaps":["Preprint not yet peer-reviewed","Whether organelle-contact role is chromatin-dependent unresolved"]},{"year":2026,"claim":"Showed tissue-specific physiological consequences of PHF2 demethylase activity in fast-twitch muscle function in vivo.","evidence":"Skeletal muscle-specific KO mice, ChIP-seq, grip strength, fiber-type phenotyping","pmids":["42006298"],"confidence":"Medium","gaps":["Single-lab study","Fiber-type specificity mechanism not explained"]},{"year":2025,"claim":"Implicated PHF2 in neuroinflammatory transcriptional control in Alzheimer's models, broadening its disease relevance.","evidence":"ChIP-seq, bidirectional Phf2 manipulation in 5xFAD mice, electrophysiology, behavior, histology","pmids":["40849543"],"confidence":"Medium","gaps":["Single-lab study","Direct vs indirect regulation of inflammatory genes not fully resolved"]},{"year":null,"claim":"How PHF2's distinct activities — H3K9me2 demethylation, SREBP1c E3 ligase activity, and demethylase-independent cohesin/heterochromatin structural roles — are coordinated within a single protein, and how upstream phosphorylation and palmitoylation switch between them, remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No unified model integrating catalytic, ligase, and structural functions","Switch between activating and repressive chromatin modes undefined","E3 ligase catalytic mechanism unmapped"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,13]},{"term_id":"GO:0140104","term_label":"molecular carrier activity","supporting_discovery_ids":[1,12]},{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[1,12]},{"term_id":"GO:0016491","term_label":"oxidoreductase activity","supporting_discovery_ids":[0,2,7]},{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[13]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[13]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[4,6,7]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,1,9]},{"term_id":"GO:0005730","term_label":"nucleolus","supporting_discovery_ids":[1,5]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[15,16,18]}],"pathway":[{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[0,1,5,16]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[4,6,7]},{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[9,11]},{"term_id":"R-HSA-69306","term_label":"DNA Replication","supporting_discovery_ids":[9,15]},{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[7,13]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[3,6,17]}],"complexes":["cohesin"],"partners":["ARID5B","RAD21","SUV39H1","CEBPA","CEBPD","TP53","AMPK","ZDHHC23"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O75151","full_name":"Lysine-specific demethylase PHF2","aliases":["GRC5","PHD finger protein 2"],"length_aa":1096,"mass_kda":120.8,"function":"Lysine demethylase that demethylates both histones and non-histone proteins (PubMed:20129925, PubMed:21167174, PubMed:21532585). Enzymatically inactive by itself, and becomes active following phosphorylation by PKA: forms a complex with ARID5B and mediates demethylation of methylated ARID5B (PubMed:21532585). Demethylation of ARID5B leads to target the PHF2-ARID5B complex to target promoters, where PHF2 mediates demethylation of dimethylated 'Lys-9' of histone H3 (H3K9me2), followed by transcription activation of target genes (PubMed:21532585). The PHF2-ARID5B complex acts as a coactivator of HNF4A in liver. PHF2 is recruited to trimethylated 'Lys-4' of histone H3 (H3K4me3) at rDNA promoters and promotes expression of rDNA (PubMed:21532585). Involved in the activation of toll-like receptor 4 (TLR4)-target inflammatory genes in macrophages by catalyzing the demethylation of trimethylated histone H4 lysine 20 (H4K20me3) at the gene promoters (By similarity)","subcellular_location":"Nucleus, nucleolus; Chromosome, centromere, kinetochore","url":"https://www.uniprot.org/uniprotkb/O75151/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/PHF2","classification":"Not Classified","n_dependent_lines":23,"n_total_lines":1208,"dependency_fraction":0.01903973509933775},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CSNK2B","stoichiometry":0.2},{"gene":"H2AFZ","stoichiometry":0.2},{"gene":"HIST2H2BE","stoichiometry":0.2},{"gene":"SSRP1","stoichiometry":0.2},{"gene":"SUPT5H","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/PHF2","total_profiled":1310},"omim":[{"mim_id":"618743","title":"PHOSPHOLIPID PHOSPHATASE 7; PLPP7","url":"https://www.omim.org/entry/618743"},{"mim_id":"606323","title":"CYTOPLASMIC FMRP-INTERACTING PROTEIN 2; CYFIP2","url":"https://www.omim.org/entry/606323"},{"mim_id":"604351","title":"PHD FINGER PROTEIN 2; PHF2","url":"https://www.omim.org/entry/604351"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoli rim","reliability":"Supported"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PHF2"},"hgnc":{"alias_symbol":["KIAA0662","JHDM1E","CENP-35","KDM7C"],"prev_symbol":[]},"alphafold":{"accession":"O75151","domains":[{"cath_id":"3.30.40.10","chopping":"7-63","consensus_level":"high","plddt":92.237,"start":7,"end":63},{"cath_id":"2.60.120.650","chopping":"88-221_231-363","consensus_level":"high","plddt":94.8992,"start":88,"end":363},{"cath_id":"1.20.58.1360","chopping":"366-446","consensus_level":"medium","plddt":92.8352,"start":366,"end":446}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O75151","model_url":"https://alphafold.ebi.ac.uk/files/AF-O75151-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O75151-F1-predicted_aligned_error_v6.png","plddt_mean":61.41},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PHF2","jax_strain_url":"https://www.jax.org/strain/search?query=PHF2"},"sequence":{"accession":"O75151","fasta_url":"https://rest.uniprot.org/uniprotkb/O75151.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O75151/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O75151"}},"corpus_meta":[{"pmid":"21532585","id":"PMC_21532585","title":"PKA-dependent 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reports","url":"https://pubmed.ncbi.nlm.nih.gov/31359606","citation_count":27,"is_preprint":false},{"pmid":"25204660","id":"PMC_25204660","title":"PHD finger protein 2 (PHF2) represses ribosomal RNA gene transcription by antagonizing PHF finger protein 8 (PHF8) and recruiting methyltransferase SUV39H1.","date":"2014","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/25204660","citation_count":20,"is_preprint":false},{"pmid":"35729160","id":"PMC_35729160","title":"HIF-1α-mediated augmentation of miRNA-18b-5p facilitates proliferation and metastasis in osteosarcoma through attenuation PHF2.","date":"2022","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/35729160","citation_count":17,"is_preprint":false},{"pmid":"27744626","id":"PMC_27744626","title":"Histone Demethylase Gene PHF2 Is Mutated in Gastric and Colorectal Cancers.","date":"2016","source":"Pathology oncology research : POR","url":"https://pubmed.ncbi.nlm.nih.gov/27744626","citation_count":12,"is_preprint":false},{"pmid":"29336484","id":"PMC_29336484","title":"Epigenetic regulation of megakaryocytic and erythroid differentiation by PHF2 histone demethylase.","date":"2018","source":"Journal of cellular physiology","url":"https://pubmed.ncbi.nlm.nih.gov/29336484","citation_count":10,"is_preprint":false},{"pmid":"28607325","id":"PMC_28607325","title":"Implication of PHF2 Expression in Clear Cell Renal Cell Carcinoma.","date":"2017","source":"Journal of pathology and translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/28607325","citation_count":10,"is_preprint":false},{"pmid":"33196691","id":"PMC_33196691","title":"KDM5A and PHF2 positively control expression of pro-metastatic genes repressed by EWS/Fli1, and promote growth and metastatic properties in Ewing sarcoma.","date":"2020","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/33196691","citation_count":9,"is_preprint":false},{"pmid":"38808662","id":"PMC_38808662","title":"PHF2 regulates genome topology and DNA replication in neural stem cells via cohesin.","date":"2024","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/38808662","citation_count":8,"is_preprint":false},{"pmid":"39748119","id":"PMC_39748119","title":"Cohesin positions the epigenetic reader Phf2 within the genome.","date":"2025","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/39748119","citation_count":8,"is_preprint":false},{"pmid":"38701072","id":"PMC_38701072","title":"PHF2 regulates sarcomeric gene transcription in myogenesis.","date":"2024","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/38701072","citation_count":5,"is_preprint":false},{"pmid":"36596360","id":"PMC_36596360","title":"A complete methyl-lysine binding aromatic cage constructed by two domains of PHF2.","date":"2022","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/36596360","citation_count":5,"is_preprint":false},{"pmid":"35558021","id":"PMC_35558021","title":"The expression and biological function of the PHF2 gene in breast cancer.","date":"2018","source":"RSC advances","url":"https://pubmed.ncbi.nlm.nih.gov/35558021","citation_count":4,"is_preprint":false},{"pmid":"26601892","id":"PMC_26601892","title":"Sequence analysis and minimal replicon determination of a new haloarchaeal plasmid pHF2 isolated from Haloferax sp. strain Q22.","date":"2015","source":"Plasmid","url":"https://pubmed.ncbi.nlm.nih.gov/26601892","citation_count":4,"is_preprint":false},{"pmid":"38890452","id":"PMC_38890452","title":"PHF2-mediated H3K9me balance orchestrates heterochromatin stability and neural progenitor proliferation.","date":"2024","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/38890452","citation_count":3,"is_preprint":false},{"pmid":"36380035","id":"PMC_36380035","title":"Circ_MBNL3 Restrains Hepatocellular Carcinoma Progression by Sponging miR-873-5p to Release PHF2.","date":"2022","source":"Biochemical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/36380035","citation_count":3,"is_preprint":false},{"pmid":"40097484","id":"PMC_40097484","title":"Comprehensive understanding of context-specific functions of PHF2 in lipid metabolic tissues.","date":"2025","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/40097484","citation_count":3,"is_preprint":false},{"pmid":"40849543","id":"PMC_40849543","title":"Histone demethylase PHF2 regulates inflammatory genes in Alzheimer's disease.","date":"2025","source":"Molecular psychiatry","url":"https://pubmed.ncbi.nlm.nih.gov/40849543","citation_count":1,"is_preprint":false},{"pmid":"41554700","id":"PMC_41554700","title":"The role of histone demethylase PHF2 as a tumour suppressor in hepatocellular carcinoma by regulating SRXN1.","date":"2026","source":"Oncogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/41554700","citation_count":0,"is_preprint":false},{"pmid":"42006298","id":"PMC_42006298","title":"PHF2 regulates grip strength via demethylation at the promoter region of the Mef2c.","date":"2026","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/42006298","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.01.18.630727","title":"The AMPKα2/PHF2 axis is critical for turning over lipid droplets during muscle stem cell fate","date":"2025-01-18","source":"bioRxiv","url":"https://doi.org/10.1101/2025.01.18.630727","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":17995,"output_tokens":5791,"usd":0.070425,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":14359,"output_tokens":5482,"usd":0.104423,"stage2_stop_reason":"end_turn"},"total_usd":0.174848,"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\": 2011,\n      \"finding\": \"PHF2 is enzymatically inactive as a H3K9me2 demethylase by itself but is activated by PKA-mediated phosphorylation; phosphorylated PHF2 then associates with the DNA-binding protein ARID5B, induces demethylation of methylated ARID5B, and the resulting complex targets gene promoters to remove repressive H3K9Me2 marks.\",\n      \"method\": \"Biochemical assays, co-immunoprecipitation, in vitro phosphorylation, ChIP, and cell-based demethylase activity assays\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — multiple orthogonal methods (biochemical demethylase assay, Co-IP, ChIP) in a focused mechanistic study; widely cited and consistent with structural work\",\n      \"pmids\": [\"21532585\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The PHD finger of PHF2 recognizes histone H3K4 trimethylation, and this interaction is essential for PHF2 occupancy and H3K9 demethylation at rDNA promoters, demonstrating cross-talk between H3K4me3 reading and H3K9 demethylase activity.\",\n      \"method\": \"Biochemical binding assays, X-ray crystallography, and ChIP\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structure of PHD–H3K4me3 interaction combined with functional ChIP validation in a single focused study\",\n      \"pmids\": [\"20129925\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The PHF2 Jumonji domain coordinates Fe2+ or Ni2+ via H249, D251, N-oxalylglycine (α-ketoglutarate analog), Y321, and one water molecule in an octahedral arrangement; a Y321H mutation (replacing the atypical tyrosine fifth ligand with histidine) does not restore demethylase activity on histone peptides in vitro, indicating additional regulatory factors are required for enzymatic activity.\",\n      \"method\": \"X-ray crystallography (crystal structures in absence and presence of metal ions), in vitro demethylase activity assay, site-directed mutagenesis (Y321H), metal binding affinity measurement\",\n      \"journal\": \"Journal of molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structures plus mutagenesis plus in vitro activity assay in one focused study\",\n      \"pmids\": [\"21167174\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"ARID5B physically associates with Sox9 and recruits PHF2 to Sox9 target gene promoters, stimulating H3K9me2 demethylation; loss of Arid5b in mice and cells increases H3K9me2 at chondrogenic gene promoters and impairs chondrogenesis, and PHF2 knockdown inhibits Sox9-induced chondrocyte differentiation.\",\n      \"method\": \"Co-immunoprecipitation, ChIP, mouse knockout model (Arid5b−/−), siRNA knockdown, differentiation assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, ChIP, in vivo KO and in vitro KD with defined phenotypic readouts, multiple orthogonal methods\",\n      \"pmids\": [\"24276541\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"PHF2 physically associates with p53 and promotes p53-driven transcription of downstream targets (e.g., p21) by demethylating the repressive H3K9me2 mark at target promoters; PHF2 depletion abolishes p21 induction by oxaliplatin/doxorubicin despite strong p53 induction in xenograft models.\",\n      \"method\": \"Co-immunoprecipitation, ChIP, siRNA knockdown, xenograft tumor model, Western blotting\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, ChIP, and in vivo xenograft with defined mechanistic outcome\",\n      \"pmids\": [\"25043306\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"PHF2 inhibits rDNA transcription by competing with the activating demethylase PHF8 for binding to rDNA promoters (through H3K4me2/3 recognition via its PHD) and by recruiting the H3K9me2/3 methyltransferase SUV39H1; demethylase activity of PHF2 is not required for this repressive function.\",\n      \"method\": \"RNAi knockdown, overexpression, ChIP, RNA polymerase I transcription assays, co-immunoprecipitation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (Co-IP, ChIP, transcription assays) with domain-function dissection (PHD vs. catalytic mutants) in one focused study\",\n      \"pmids\": [\"25204660\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"PHF2 physically interacts with the adipogenic transcription factors C/EBPα and C/EBPδ, binds their target gene promoters, and demethylates H3K9me2 there to activate adipogenic gene expression; PHF2 knockdown reduces lipid accumulation and metabolic gene expression during adipocyte differentiation.\",\n      \"method\": \"Co-immunoprecipitation, ChIP, stable shRNA knockdown in 3T3-L1 cells, cDNA microarray, qRT-PCR, Western blotting\",\n      \"journal\": \"Molecules and cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP and ChIP with functional KD phenotype in a single lab study\",\n      \"pmids\": [\"25266703\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"PHF2 functions as a transcriptional co-activator of ChREBP by erasing H3K9me2 marks at ChREBP-regulated gene promoters in hepatocytes, facilitating lipogenesis; PHF2 also activates Nrf2 target genes, redirecting glucose toward the pentose phosphate pathway and protecting from oxidative stress in diet-induced obesity.\",\n      \"method\": \"ChIP, mouse genetic models, siRNA knockdown, metabolic flux analyses, lipidomics\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP linking H3K9me2 removal to specific promoters, validated in vivo mouse models plus in vitro mechanistic assays across multiple orthogonal methods\",\n      \"pmids\": [\"29844386\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"PHF2 binds the p53 promoter, demethylates H3K9me2 in that region, and thereby regulates p53 expression; during megakaryocytic and erythroid differentiation, PHF2 downregulation parallels p53 downregulation and knockdown of PHF2 promotes differentiation.\",\n      \"method\": \"ChIP, co-immunoprecipitation, siRNA knockdown, Western blotting, differentiation assays in K562 and CD34+ cells\",\n      \"journal\": \"Journal of cellular physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP and KD with defined readout but single lab study\",\n      \"pmids\": [\"29336484\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"PHF2 controls expression of DNA replication and cell cycle progression genes in neural progenitors by maintaining low H3K9me3 levels at their promoters; PHF2 depletion causes R-loop accumulation, DNA damage, and cell cycle arrest, revealing PHF2 as a guardian of genome stability in neural development.\",\n      \"method\": \"siRNA knockdown in neural progenitors, genome-wide ChIP-seq, R-loop detection (S9.6 immunostaining), DNA damage assays (γH2AX), cell cycle analysis, in vivo chicken spinal cord electroporation\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genome-wide ChIP-seq plus functional KD with multiple orthogonal readouts (R-loops, DNA damage, cell cycle) and in vivo validation\",\n      \"pmids\": [\"31488723\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"PHF2 promotes long-term memory consolidation by epigenetically reinforcing the TrkB-CREB signaling pathway; PHF2 knockdown in mouse hippocampus impairs memory formation while PHF2 transgenic overexpression enhances it, and PHF2 elevates field EPSP and NMDA receptor-mediated EPSC in CA1 neurons.\",\n      \"method\": \"Lentiviral shRNA knockdown in hippocampus, transgenic overexpression, behavioral tests (fear conditioning), electrophysiology (LTP recordings), ChIP\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo genetic manipulation with electrophysiology and behavioral readouts plus ChIP, multiple orthogonal methods in one study\",\n      \"pmids\": [\"31359606\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"PHF2 promotes DNA repair by homologous recombination by controlling CtIP-dependent resection of DNA double-strand breaks; PHF2 knockdown decreases CtIP and BRCA1 protein and mRNA levels (dependent on PHF2 demethylase activity), impairs BRCA1 and RPA focus formation, delays 53BP1 foci resolution, and reduces Rad51 focus formation and HDR efficiency.\",\n      \"method\": \"siRNA knockdown, immunofluorescence (IRIF foci), HR reporter assay, RPA phosphorylation assays, qRT-PCR, Western blotting, sensitivity assays (PARPi)\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal functional readouts (focus formation, HR assay, demethylase-dead mutant) in one focused study\",\n      \"pmids\": [\"32232336\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"The PHF2 PHD and Jumonji domains together form a complete methyl-lysine binding aromatic cage at their interface: H3K4me3 (and VRK1 K4me3) peptides bind across both domains with affinities (KD ~160 nM for H3, ~42 nM for VRK1) 4–21× higher than for the isolated PHD alone; crystal structures show R2 of the peptide engaging acidic residues on both domains and K4me3 encircled by aromatic residues from both domains.\",\n      \"method\": \"X-ray crystallography, fluorescence polarization binding assays, peptide binding studies\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structures with quantitative binding measurements identifying structural basis of bivalent recognition\",\n      \"pmids\": [\"36596360\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PHF2 functions as an E3 ubiquitin ligase that directly ubiquitinates and destabilizes SREBP1c, thereby suppressing SREBP1c-dependent lipogenesis in hepatocellular carcinoma; the palmitoyltransferase ZDHHC23 palmitoylates PHF2, enhancing its ubiquitin-dependent proteasomal degradation, which relieves SREBP1c suppression and promotes lipid reprogramming.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assays, palmitoylation assays, protein stability assays, siRNA knockdown, overexpression in HepG2 and Hep3B cells\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — in vitro ubiquitination and palmitoylation assays, Co-IP, and functional protein stability measurements with defined substrates\",\n      \"pmids\": [\"37828054\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"AMPKα2 directly phosphorylates PHF2 at Ser655, enhancing PHF2 demethylase activity toward H3K9me2 and promoting transcription of epithelial genes (e.g., CDH1); a phospho-mimetic PHF2-S655E mutant reduces H3K9me2 and suppresses lung cancer metastasis, while S655A mutant reverses the anti-metastatic effect of metformin.\",\n      \"method\": \"In vitro kinase assay, co-immunoprecipitation (PHF2–AMPKα2), site-directed mutagenesis (S655E and S655A), H3K9me2 ChIP, loss-of-function (PHF2 KO), cell migration/invasion assays, mouse metastasis model\",\n      \"journal\": \"Signal transduction and targeted therapy\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vitro kinase assay plus mutagenesis plus ChIP plus in vivo metastasis model with multiple orthogonal methods\",\n      \"pmids\": [\"36872368\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PHF2 associates with RAD21, a core cohesin subunit, to regulate DNA replication in mouse neural stem cells; PHF2/RAD21 co-bound genomic regions resemble active replication origins; PHF2 loss weakens TAD boundaries and chromatin loops at co-bound loci due to reduced RAD21 occupancy and activates dormant replication origins; notably, PHF2's histone demethylase activity is dispensable for this function.\",\n      \"method\": \"Co-immunoprecipitation, ChIP-seq, Hi-C (genome topology), DNA replication origin mapping, CRISPR/Cas9 PHF2 KO in mouse NSC, catalytic-dead mutant rescue\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, genome-wide ChIP-seq, Hi-C, and KO with mechanistic rescue using catalytic-dead mutant in one focused study\",\n      \"pmids\": [\"38808662\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PHF2 interacts with heterochromatin components and localizes to pericentromeric heterochromatin (PcH) boundaries where it maintains transcriptional activity essential for silencing satellite repeats; PHF2 depletion increases heterochromatic repeat transcription, decreases H3K9me3 levels, and disrupts PcH organization, causing DNA damage; both the PHD and catalytic Jumonji domains are required for PcH stability.\",\n      \"method\": \"Mass spectrometry (Co-IP interactome), ChIP-seq, RNA-seq, immunofluorescence, CRISPR/Cas9 KO, domain-deletion mutants\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mass spectrometry Co-IP, genome-wide ChIP-seq, RNA-seq, and domain dissection in one focused study\",\n      \"pmids\": [\"38890452\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PHF2 binds to promoter regions of sarcomeric genes (e.g., Mybpc2, Mef2c, Myh7) and demethylates H3K9me2 there; PHF2 KO in C2C12 myoblasts by CRISPR/Cas9 severely reduces sarcomeric gene expression and increases H3K9me2 at those loci during differentiation.\",\n      \"method\": \"CRISPR/Cas9 knockout, RNA-seq, ChIP (H3K9me2), qRT-PCR, Western blotting, differentiation assays\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR KO with RNA-seq and ChIP validation, single lab study\",\n      \"pmids\": [\"38701072\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Cohesin translocates PHF2 through the genome via DNA loop extrusion; PHF2 binds H3K4me3 nucleosomes at active TSSs and also co-localizes with cohesin; cohesin depletion reduces PHF2 binding at sites lacking H3K4me3; conversely, PHF2 depletion reduces cohesin binding at TSSs lacking CTCF and decreases short cohesin loops while increasing heterochromatic B compartment size.\",\n      \"method\": \"ChIP-seq, co-immunoprecipitation, conditional cohesin depletion (auxin-inducible degron), Wapl/CTCF depletion, Hi-C\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal genome-wide approaches (ChIP-seq, Hi-C) combined with reciprocal depletion experiments establishing bidirectional functional relationship\",\n      \"pmids\": [\"39748119\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PHF2 promotes lipid droplet homeostasis in muscle stem cells (MuSCs) during regenerative myogenesis by facilitating contacts between lipid droplets and mitochondria; PHF2 loss causes lipid droplet accumulation, mitochondrial dysfunction, and impaired regeneration; expression of an AMPKα2-phospho-mimetic PHF2 mutant rescues the phenotype, placing PHF2 downstream of AMPKα2 in this pathway.\",\n      \"method\": \"Mouse muscle regeneration model, CRISPR/Cas9 PHF2 KO, phospho-mimetic mutant rescue, live-cell imaging of lipid droplet–mitochondria contacts, functional regeneration assays\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo KO with mechanistic rescue by phospho-mimetic mutant; preprint, not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.01.18.630727\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"PHF2 binds to TSS-downstream regions of Mef2c and other muscle-function genes in fast-twitch muscle fibers and demethylates H3K9me2 there; skeletal muscle-specific PHF2 knockout mice show significantly reduced grip strength with preferential effects in fast-twitch muscles.\",\n      \"method\": \"Skeletal muscle-specific Phf2 KO mice, ChIP-seq, grip strength measurements, fiber-type-specific phenotyping\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — tissue-specific KO in vivo with ChIP-seq, single lab study\",\n      \"pmids\": [\"42006298\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PHF2 (KDM7C) regulates inflammatory gene expression in Alzheimer's disease contexts: ChIP-seq combined with bidirectional Phf2 manipulation shows PHF2 controls Stat3, Nfkbia, Nfkb2, Tnfrsf1a, and other neuroinflammation genes; Phf2 knockdown in 5xFAD mice reduces microglial/astrocyte activation and restores glutamatergic synaptic function.\",\n      \"method\": \"ChIP-seq, siRNA knockdown in 5xFAD mice, qRT-PCR, immunohistochemistry, electrophysiology, behavioral testing (Barnes maze)\",\n      \"journal\": \"Molecular psychiatry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-seq plus in vivo KD with multiple readouts (electrophysiology, behavior, histology), single lab study\",\n      \"pmids\": [\"40849543\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PHF2 is a Jumonji-C domain H3K9me2 demethylase whose catalytic activity requires regulatory phosphorylation (by PKA at an unspecified site or by AMPK at S655) and whose PHD finger binds H3K4me3 to co-localize the enzyme with active promoters; it operates in complex with DNA-binding partners (ARID5B, C/EBPα/δ, ChREBP, p53, Sox9 via Arid5b) to selectively erase repressive H3K9me2 at target gene promoters, and additionally functions as an E3 ubiquitin ligase for SREBP1c, recruits SUV39H1 to repress rDNA transcription, interacts with cohesin (RAD21) to organize TAD boundaries and regulate DNA replication origins, and maintains pericentromeric heterochromatin stability—with its demethylase activity being dispensable for the cohesin-related topological functions.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PHF2 is a Jumonji-C family histone demethylase that erases the repressive H3K9me2 mark at target gene promoters to activate transcription across diverse developmental and metabolic programs [#0, #7]. Its catalytic Jumonji domain coordinates Fe2+ and α-ketoglutarate in an octahedral arrangement, but the isolated enzyme is intrinsically inactive on histone substrates and requires regulatory input — PKA-mediated phosphorylation licenses demethylation and assembly with the DNA-binding partner ARID5B [#0, #2], while AMPKα2 phosphorylation at Ser655 enhances H3K9me2 demethylase activity [#14]. Promoter targeting is achieved through a bivalent reader module in which the PHD finger and Jumonji domain together form a methyl-lysine aromatic cage that binds H3K4me3 with high affinity, coupling recognition of active chromatin to H3K9 demethylation [#1, #12]. PHF2 is recruited to specific loci by sequence-specific transcription factors — ARID5B (including ARID5B–Sox9 complexes), C/EBPα/δ, ChREBP, and p53 — to selectively activate chondrogenic, adipogenic, lipogenic, and p53-target genes [#3, #4, #6, #7]. Beyond gene activation, PHF2 has repressive and structural functions that are independent of its demethylase activity: it competes with PHF8 and recruits the methyltransferase SUV39H1 to silence rDNA transcription [#5], and it associates with the cohesin subunit RAD21 to organize TAD boundaries, chromatin loops, and DNA replication origins, with cohesin loop extrusion translocating PHF2 across the genome [#15, #18]. PHF2 functions as a guardian of genome stability, maintaining pericentromeric heterochromatin integrity, suppressing R-loop accumulation and DNA damage, and promoting CtIP/BRCA1-dependent homologous recombination repair [#9, #11, #16]. PHF2 additionally acts as an E3 ubiquitin ligase that ubiquitinates and destabilizes SREBP1c to restrain lipogenesis [#13]. Through these activities it controls neural progenitor proliferation, memory consolidation, myogenic and metabolic differentiation, and tumor and neuroinflammatory phenotypes [#9, #10, #14, #17, #21].\",\n  \"teleology\": [\n    {\n      \"year\": 2010,\n      \"claim\": \"Established how PHF2 is targeted to chromatin and linked H3K4me3 reading to H3K9 demethylase output, defining the basic reader–eraser cross-talk.\",\n      \"evidence\": \"X-ray crystallography of the PHD–H3K4me3 interaction with ChIP validation at rDNA promoters\",\n      \"pmids\": [\"20129925\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve why the isolated enzyme lacks robust catalytic activity\", \"Promoter selectivity beyond rDNA not addressed\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Defined the catalytic Jumonji active-site architecture and revealed that an atypical fifth metal ligand alone does not account for the enzyme's inactivity, predicting a requirement for additional regulatory factors.\",\n      \"evidence\": \"Crystal structures with/without metal, in vitro demethylase assay, and Y321H mutagenesis\",\n      \"pmids\": [\"21167174\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The activating factor/modification was not identified in this study\", \"No histone substrate turnover demonstrated in vitro\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Resolved the activation paradox by showing PHF2 is inactive alone and requires PKA phosphorylation plus ARID5B partnership to demethylate target promoters.\",\n      \"evidence\": \"In vitro phosphorylation, Co-IP, ChIP, and cell-based demethylase assays\",\n      \"pmids\": [\"21532585\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The specific PKA phosphosite was not defined\", \"Mechanism by which phosphorylation activates catalysis unresolved\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Showed PHF2 is recruited by transcription-factor complexes (ARID5B–Sox9) to drive a defined developmental program, establishing partner-directed promoter targeting in vivo.\",\n      \"evidence\": \"Reciprocal Co-IP, ChIP, Arid5b knockout mice, siRNA, and chondrocyte differentiation assays\",\n      \"pmids\": [\"24276541\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether PHF2 phosphorylation status governs Sox9-target activation not tested\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Extended partner-directed activation to multiple transcription factors (p53, C/EBPα/δ) and showed PHF2 is required for their downstream transcriptional output and phenotypes.\",\n      \"evidence\": \"Co-IP, ChIP, siRNA/shRNA knockdown, xenograft and adipocyte differentiation models\",\n      \"pmids\": [\"25043306\", \"25266703\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Adipogenic role rests on a single-lab Medium-confidence study\", \"Direct vs indirect promoter binding not fully separated\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Revealed a demethylase-independent repressive function, showing PHF2 can silence rDNA by competing with PHF8 and recruiting SUV39H1.\",\n      \"evidence\": \"RNAi, overexpression, ChIP, Pol I transcription assays, Co-IP, and catalytic-mutant dissection\",\n      \"pmids\": [\"25204660\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How PHF2 toggles between activating and repressive modes at different loci is unresolved\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Connected PHF2 demethylase activity to systemic lipid and oxidative-stress metabolism through ChREBP co-activation and Nrf2 target regulation.\",\n      \"evidence\": \"ChIP, mouse genetic models, siRNA, metabolic flux and lipidomic analyses\",\n      \"pmids\": [\"29844386\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Upstream signal coupling metabolic state to PHF2 activity not defined here\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Identified PHF2 as a genome-stability factor in neural progenitors that keeps replication/cell-cycle genes accessible and prevents R-loop-associated DNA damage.\",\n      \"evidence\": \"siRNA, genome-wide ChIP-seq, S9.6 R-loop staining, γH2AX, cell-cycle analysis, in vivo electroporation\",\n      \"pmids\": [\"31488723\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether genome instability is a direct demethylase effect or secondary to transcriptional defects not fully separated\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Showed PHF2 promotes homologous recombination repair by demethylase-dependent control of CtIP/BRCA1 expression and DSB resection.\",\n      \"evidence\": \"siRNA, IRIF immunofluorescence, HR reporter assay, RPA phosphorylation, PARPi sensitivity\",\n      \"pmids\": [\"32232336\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct chromatin recruitment to break sites not demonstrated\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined the structural basis of high-affinity methyl-lysine reading, showing PHD and Jumonji domains form a single bivalent aromatic cage rather than the PHD acting alone.\",\n      \"evidence\": \"X-ray crystallography and fluorescence polarization binding with H3 and VRK1 peptides\",\n      \"pmids\": [\"36596360\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of VRK1-K4me3 binding not established\", \"How bivalent reading couples to catalysis unresolved\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Uncovered a non-demethylase enzymatic activity, defining PHF2 as an E3 ubiquitin ligase for SREBP1c that is itself regulated by ZDHHC23 palmitoylation-driven degradation.\",\n      \"evidence\": \"Co-IP, in vitro ubiquitination and palmitoylation assays, protein stability assays in hepatoma cells\",\n      \"pmids\": [\"37828054\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Catalytic residues mediating ligase activity not mapped\", \"Generality of E3 activity beyond SREBP1c unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identified AMPKα2 phosphorylation at Ser655 as a defined activating modification that boosts H3K9me2 demethylation and suppresses metastasis, providing a kinase-to-chromatin axis.\",\n      \"evidence\": \"In vitro kinase assay, Co-IP, S655E/S655A mutagenesis, ChIP, and mouse metastasis model\",\n      \"pmids\": [\"36872368\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Relationship between the AMPK Ser655 and earlier PKA phosphorylation events not reconciled\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Established demethylase-independent structural roles, showing PHF2 partners with cohesin/RAD21 to set TAD boundaries, loops, and replication origins.\",\n      \"evidence\": \"Co-IP, ChIP-seq, Hi-C, replication origin mapping, CRISPR KO with catalytic-dead rescue in neural stem cells\",\n      \"pmids\": [\"38808662\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct physical contact interface between PHF2 and cohesin not mapped\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Showed PHF2 maintains pericentromeric heterochromatin and satellite silencing requiring both PHD and Jumonji domains, linking it to genome integrity at repeats.\",\n      \"evidence\": \"Mass-spec interactome, ChIP-seq, RNA-seq, immunofluorescence, CRISPR KO, domain-deletion mutants\",\n      \"pmids\": [\"38890452\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How an H3K9me2 demethylase sustains H3K9me3-rich heterochromatin mechanistically unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Demonstrated that cohesin loop extrusion actively translocates PHF2 genome-wide and that the relationship is reciprocal, with PHF2 stabilizing cohesin at CTCF-independent TSSs.\",\n      \"evidence\": \"ChIP-seq, Co-IP, auxin-inducible cohesin/Wapl/CTCF depletion, and Hi-C\",\n      \"pmids\": [\"39748119\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of PHF2 hand-off to cohesin not defined\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Extended the AMPK–PHF2 axis to muscle stem cell metabolism, linking PHF2 to lipid droplet–mitochondria contacts and regeneration.\",\n      \"evidence\": \"Mouse regeneration model, CRISPR KO, phospho-mimetic rescue, live-cell organelle-contact imaging (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.01.18.630727\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint not yet peer-reviewed\", \"Whether organelle-contact role is chromatin-dependent unresolved\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Showed tissue-specific physiological consequences of PHF2 demethylase activity in fast-twitch muscle function in vivo.\",\n      \"evidence\": \"Skeletal muscle-specific KO mice, ChIP-seq, grip strength, fiber-type phenotyping\",\n      \"pmids\": [\"42006298\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"Fiber-type specificity mechanism not explained\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Implicated PHF2 in neuroinflammatory transcriptional control in Alzheimer's models, broadening its disease relevance.\",\n      \"evidence\": \"ChIP-seq, bidirectional Phf2 manipulation in 5xFAD mice, electrophysiology, behavior, histology\",\n      \"pmids\": [\"40849543\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"Direct vs indirect regulation of inflammatory genes not fully resolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How PHF2's distinct activities — H3K9me2 demethylation, SREBP1c E3 ligase activity, and demethylase-independent cohesin/heterochromatin structural roles — are coordinated within a single protein, and how upstream phosphorylation and palmitoylation switch between them, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No unified model integrating catalytic, ligase, and structural functions\", \"Switch between activating and repressive chromatin modes undefined\", \"E3 ligase catalytic mechanism unmapped\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 13]},\n      {\"term_id\": \"GO:0140104\", \"supporting_discovery_ids\": [1, 12]},\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [1, 12]},\n      {\"term_id\": \"GO:0016491\", \"supporting_discovery_ids\": [0, 2, 7]},\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [13]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [13]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [4, 6, 7]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1, 9]},\n      {\"term_id\": \"GO:0005730\", \"supporting_discovery_ids\": [1, 5]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [15, 16, 18]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [0, 1, 5, 16]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [4, 6, 7]},\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [9, 11]},\n      {\"term_id\": \"R-HSA-69306\", \"supporting_discovery_ids\": [9, 15]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [7, 13]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [3, 6, 17]}\n    ],\n    \"complexes\": [\"cohesin\"],\n    \"partners\": [\"ARID5B\", \"RAD21\", \"SUV39H1\", \"CEBPA\", \"CEBPD\", \"TP53\", \"AMPK\", \"ZDHHC23\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}