{"gene":"PCGF5","run_date":"2026-06-10T05:19:53","timeline":{"discoveries":[{"year":2018,"finding":"PCGF5 is required for neural differentiation of mouse embryonic stem cells (mESCs); loss of PCGF5 blocks neural differentiation by activating the SMAD2/TGF-β signaling pathway and impairs reduction of H2AK119ub1 and H3K27me3 around neural-specific genes, keeping them repressed.","method":"CRISPR/Cas9 knockout in mESCs, RNA-seq, ChIP-seq, rescue experiments","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean KO with defined cellular phenotype, ChIP-seq for histone marks, pathway placement via SMAD2/TGF-β, multiple orthogonal methods in a single rigorous study","pmids":["29765032"],"is_preprint":false},{"year":2017,"finding":"PCGF3 and PCGF5 function as transcriptional activators in ES cells through interaction with the pluripotency factor Tex10 and the co-activator p300; Pcgf3/5 deletion reduces Tex10 and p300 occupancy at target genes and globally reduces H2AK119ub1 levels; Pcgf3/5 are required for mesoderm differentiation.","method":"CRISPR/Cas9 knockout, RNA-seq, proteomic interactome (MS), ChIP/promoter occupancy analysis, in vitro and in vivo differentiation assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-IP/MS interactome, ChIP occupancy, KO phenotype, multiple orthogonal methods in one study","pmids":["29054931"],"is_preprint":false},{"year":2016,"finding":"Pcgf5 deletion in hematopoietic stem and progenitor cells (HSPCs) causes significant reduction in global H2AK119ub1 levels but does not impair HSPC self-renewal or repopulating capacity, indicating that Pcgf5-containing PRC1 functions as a histone modifier in vivo but its role in HSPCs is compensated by other PRC1-related complexes.","method":"Conditional Cre-ERT knockout in mice, competitive bone marrow transplantation, ChIP-seq for H2AK119ub1, flow cytometry","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO with in vivo competitive repopulation assay, ChIP-seq, multiple orthogonal readouts","pmids":["27136092"],"is_preprint":false},{"year":2018,"finding":"During E. chaffeensis infection, the bacterial effector TRP120 interacts with PCGF5 (and other PCGF isoforms) in the nucleus early in infection; PCGF isoforms are redistributed from the nucleus to the ehrlichial vacuole and subsequently undergo proteasomal degradation; this disrupts PRC1-mediated H2AK119ub1 repressive marks and alters HOXB/HOXC gene transcription; siRNA knockdown of PCGF isoforms increases E. chaffeensis infection.","method":"Ectopic expression and co-immunoprecipitation of TRP120, confocal immunofluorescence microscopy, siRNA knockdown, proteasome inhibitor treatment, ChIP for H2AK119ub1","journal":"Infection and immunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — co-IP, siRNA KD with infection phenotype, ChIP, and live-imaging redistribution, multiple orthogonal methods","pmids":["29358333"],"is_preprint":false},{"year":2017,"finding":"The E. chaffeensis effector TRP120 acts as a HECT E3 ubiquitin ligase that polyubiquitinates PCGF5, leading to reduced PCGF5 protein levels; this activity depends on Nedd4L, which also mediates TRP120 ubiquitination; Nedd4L knockdown reduces TRP120-Ub, decreases ehrlichial infection, and reduces PCGF5 recruitment to ehrlichial inclusions.","method":"In vitro ubiquitination assay with purified TRP120 and E2 enzymes, ectopic expression of HECT catalytic-site mutant, Nedd4L siRNA knockdown, immunoprecipitation","journal":"Infection and immunity","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstituted ubiquitination assay with catalytic-site mutagenesis confirmed in cells, replicated with siRNA knockdown","pmids":["28630068"],"is_preprint":false},{"year":2018,"finding":"During blood specification, SCL/TAL1 directly activates expression of PCGF5 (along with RYBP) as part of a Polycomb-PRC1 co-repressor program that suppresses alternative cardiac/paraxial lineage gene expression; PCGF5 and RYBP co-occupy SCL target genes including cardiac/paraxial loci; reduction of Rybp expression mimics the Scl-null cardiac phenotype.","method":"Scl-null mouse model, RNA-seq, ChIP-seq for RYBP and H2AK119ub1/H3K27me3, genome-wide ChIP, genetic rescue (Eto2/Rybp knockdown)","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-seq and genetic epistasis in single study; PCGF5-specific mechanistic contribution is inferred from co-occupancy data rather than direct PCGF5 KO in this context","pmids":["30560907"],"is_preprint":false},{"year":2018,"finding":"A variant PRC1 complex incorporating PCGF3 and PCGF5 represses Meis2 expression in the distal mouse forelimb bud; PcG factors and retinoic acid-related signals antagonize each other to polarize Meis2 expression along the proximal-distal axis.","method":"Mouse genetic models, mathematical modeling, in vivo gene expression analysis","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo mouse model with defined genetic pathway, but PCGF5-specific contribution inferred alongside PCGF3 with limited orthogonal mechanistic dissection of PCGF5 alone","pmids":["30190278"],"is_preprint":false},{"year":2009,"finding":"The E. chaffeensis TRP47 effector interacts with PCGF5; the amino-terminal truncated form of p47 containing tandem repeats interacts with PCGF5 but not with FYN, PTPN2, or CAP1, establishing that the TR domain of p47 is sufficient for PCGF5 interaction; interaction confirmed by co-immunoprecipitation and colocalization in HeLa cells.","method":"Yeast two-hybrid, co-immunoprecipitation, colocalization by confocal fluorescence microscopy in HeLa cells transfected with AcGFP1-p47","journal":"Infection and immunity","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal confirmation by yeast two-hybrid and co-IP with colocalization, domain-mapping experiment, single lab","pmids":["19273555"],"is_preprint":false},{"year":2011,"finding":"The E. chaffeensis TRP120 effector interacts with PCGF5; the TR domain of TRP120 is sufficient for interaction with PCGF5 specifically, while other host targets require additional TRP120 domains; TRP120 and PCGF5 strongly colocalize in HeLa cells and near ehrlichial morulae.","method":"Yeast two-hybrid cotransformation confirmation, colocalization by fluorescence microscopy in HeLa cells","journal":"Infection and immunity","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — yeast two-hybrid and colocalization; domain mapping identifies TR domain as sufficient, replicated in Ehrlichia infection context across multiple papers","pmids":["21859857"],"is_preprint":false},{"year":2019,"finding":"PCGF5 interacts exclusively with the long isoform of AUTS2 (not the short isoform), as identified by yeast two-hybrid screen; PCGF3 expression levels influence the ability of the long AUTS2 isoform to activate or repress transcription, placing PCGF5 in the long-isoform-specific AUTS2-PRC1 complex.","method":"Yeast two-hybrid screen, reporter transcriptional assays","journal":"Molecular psychiatry","confidence":"Low","confidence_rationale":"Tier 3 / Weak — yeast two-hybrid only for PCGF5 interaction, single lab, no direct biochemical confirmation of PCGF5-AUTS2 complex reported in this abstract","pmids":["30953002"],"is_preprint":false},{"year":2014,"finding":"SUMO pathway inhibition significantly reduced recruitment of PCGF5 to E. chaffeensis ehrlichial inclusions (TRP120-interacting protein), demonstrating that SUMO-dependent interactions are required for PCGF5 localization to the bacterial inclusion during infection.","method":"Small-molecule SUMO pathway inhibitor treatment, confocal colocalization microscopy, co-immunoprecipitation","journal":"Infection and immunity","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pharmacological perturbation with direct imaging readout in infection context, co-IP confirmation, single lab","pmids":["25047847"],"is_preprint":false},{"year":2016,"finding":"In T-ALL cells, PCGF5 represses transcription of the NKL homeobox gene MSX1, while AUTS2 (as part of PRC1.5/PRC1 subtype 5) activates it; expression profiling and functional analyses demonstrate opposing activities of PCGF5 and AUTS2 on MSX1 transcription.","method":"Expression profiling, forced-expression experiments, pharmacological EZH2 inhibition, H3K27me3 ChIP analysis in T-ALL cell lines","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional KD/OE with defined transcriptional readout and ChIP, single lab, multiple methods","pmids":["27322685"],"is_preprint":false},{"year":2024,"finding":"Pcgf5 suppresses Wnt3 expression via activation of the Notch1/Hes1 signaling axis, thereby governing the differentiation fate of neural stem cells; knockdown of Pcgf5 in P19 cells decreases neuronal markers (Sox2, Zfp521, Pax6) while increasing pluripotency markers (Oct4, Nanog), and knockdown of pcgf5a by morpholino in zebrafish causes neurodevelopmental defects.","method":"siRNA knockdown and overexpression in P19 cells, zebrafish morpholino knockdown, qRT-PCR, in vivo neural marker analysis","journal":"Heliyon","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KD and OE with defined phenotypic readout in two model systems (P19 cells + zebrafish), pathway placement via Notch1/Hes1/Wnt3 axis, single lab","pmids":["38533065"],"is_preprint":false},{"year":2020,"finding":"Pcgf5 knockout in mESCs delays generation of the three germ layers (especially ectoderm), impairs epithelial-mesenchymal transition during embryoid body morphogenesis, differentially affects Nodal and Wnt signaling gene expression, and induces repression of Notch pathway genes leading to enhanced cardiomyocyte maturation and dampened ectodermal-neural differentiation.","method":"CRISPR/Cas9 KO mESCs, embryoid body differentiation protocol, gene expression analysis","journal":"Development, growth & differentiation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean CRISPR KO with defined developmental phenotypes and pathway-level gene expression analysis, single lab, single study","pmids":["32130724"],"is_preprint":false},{"year":2025,"finding":"Pcgf5 forms a chimeric transcript with MT2C_Mm (MERVL long terminal repeat) during zygotic genome activation (ZGA); Pcgf5 knockdown reduces H3K27me3 and H2AK119ub1 in mouse preimplantation embryos, upregulates ZGA genes and imprinting genes, and impairs H3K27me3 addition to the maternal Xist region, implicating Pcgf5 in noncanonical imprinting and Xist regulation.","method":"Morpholino knockdown in mouse embryos, ChIP for H3K27me3 and H2AK119ub1, developmental rate tracking, gene expression analysis","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean KD with ChIP readout and multiple phenotypic endpoints in preimplantation embryos; preprint, not yet peer-reviewed","pmids":["bio_10.1101_2025.01.24.632300"],"is_preprint":true},{"year":2023,"finding":"PCGF5 is among a minority of Xist-recruited proteins that form Xist-seeded protein assemblies at the inactive X chromosome, placing it in the supramolecular assembly that drives X-chromosome inactivation.","method":"Protein assembly and localization analysis at the inactive X chromosome (described in the context of CIZ1-focused study)","journal":"Frontiers in cell and developmental biology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — PCGF5 listed as one of several proteins forming Xist-seeded assemblies; mechanistic detail for PCGF5 specifically is not elaborated in this abstract","pmids":["38155839"],"is_preprint":false},{"year":2025,"finding":"WDR68/DCAF7 interacts with PCGF5 (and AUTS2) as identified by co-immunoprecipitation coupled with LC-MS, placing PCGF5 in the WDR68 interactome relevant to mouse embryonic development.","method":"Co-immunoprecipitation combined with liquid chromatography-mass spectrometry (Co-IP/LC-MS)","journal":"Journal of translational medicine","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single Co-IP/MS experiment identifying PCGF5 as WDR68 interactor; no functional follow-up specific to PCGF5 reported","pmids":["40462101"],"is_preprint":false}],"current_model":"PCGF5 is a core subunit of non-canonical Polycomb Repressive Complex 1 (PRC1.5) that catalyzes H2AK119ub1 and maintains H3K27me3 at target loci; it functions as a context-dependent transcriptional regulator—repressing TGF-β/SMAD2 and alternative lineage genes while facilitating neural and mesodermal differentiation—through interactions with RING1A/B, RYBP, AUTS2, Tex10, and p300, and is targeted for proteasomal degradation by the bacterial E3 ubiquitin ligase TRP120 during Ehrlichia chaffeensis infection to disrupt PRC1-mediated host gene repression."},"narrative":{"mechanistic_narrative":"PCGF5 is a subunit of a variant (non-canonical) Polycomb Repressive Complex 1 that controls the histone modifications H2AK119ub1 and H3K27me3 to direct lineage choice during differentiation [PMID:29765032, PMID:27136092]. Loss of PCGF5 globally reduces H2AK119ub1 in vivo, establishing it as a bona fide effector of PRC1 histone-modifying activity [PMID:27136092]. Its transcriptional output is context-dependent: in mouse ES cells PCGF5 represses the SMAD2/TGF-β pathway and resolves repressive marks around neural genes to permit neural differentiation [PMID:29765032], yet together with PCGF3 it can act as a transcriptional activator through the pluripotency factor Tex10 and the co-activator p300 and is required for mesoderm differentiation [PMID:29054931]. PCGF5 partitions cell fate during embryoid body and germ-layer formation, modulating Nodal, Wnt, and Notch signaling [PMID:32130724], and governs neural stem cell fate by suppressing Wnt3 via the Notch1/Hes1 axis [PMID:38533065]. Within these complexes PCGF5 partners with RYBP in an SCL/TAL1-driven program that silences alternative cardiac/paraxial lineage genes during blood specification [PMID:30560907] and with the long isoform of AUTS2, with which it exerts opposing transcriptional effects on the homeobox target MSX1 [PMID:27322685]. PCGF5 is also a host target hijacked during Ehrlichia chaffeensis infection: the bacterial effector TRP120 functions as a HECT E3 ubiquitin ligase that polyubiquitinates PCGF5 in a Nedd4L-dependent manner, driving its proteasomal degradation, redistribution to the ehrlichial vacuole, and loss of PRC1-mediated repression of HOX loci [PMID:29358333, PMID:28630068].","teleology":[{"year":2009,"claim":"Established the earliest physical link between PCGF5 and a pathogen effector, defining the tandem-repeat domain as the interaction module.","evidence":"Yeast two-hybrid, co-IP, and confocal colocalization of E. chaffeensis TRP47 with PCGF5 in HeLa cells","pmids":["19273555"],"confidence":"Medium","gaps":["Functional consequence of the interaction for PCGF5 or infection not tested","No link to PCGF5's chromatin function established at this stage"]},{"year":2011,"claim":"Identified a second Ehrlichia effector, TRP120, as a PCGF5-binding protein, showing its TR domain is specifically sufficient for the interaction.","evidence":"Yeast two-hybrid cotransformation and fluorescence colocalization near ehrlichial morulae in HeLa cells","pmids":["21859857"],"confidence":"Medium","gaps":["Mechanism of PCGF5 recruitment unresolved","No demonstration of effect on host transcription"]},{"year":2014,"claim":"Showed that PCGF5 recruitment to the pathogen inclusion is SUMO-dependent, defining a post-translational requirement for its relocalization during infection.","evidence":"Small-molecule SUMO pathway inhibition with confocal colocalization and co-IP in infected cells","pmids":["25047847"],"confidence":"Medium","gaps":["Direct SUMO substrate (PCGF5 vs TRP120) not pinpointed","Consequence for PCGF5 chromatin targets not measured"]},{"year":2016,"claim":"Tested whether PCGF5 is required for its histone mark in vivo, revealing it is a global H2AK119ub1 modifier but functionally redundant in hematopoietic stem cells.","evidence":"Conditional Cre-ERT knockout in mice, competitive bone marrow transplantation, and H2AK119ub1 ChIP-seq","pmids":["27136092"],"confidence":"High","gaps":["Identity of compensating PRC1-related complexes not defined","Did not reveal a non-redundant lineage context"]},{"year":2016,"claim":"Demonstrated context-specific repression by PCGF5 of a homeobox target, contrasting it with the activating activity of AUTS2 in the same complex subtype.","evidence":"Forced expression, EZH2 inhibition, and H3K27me3 ChIP on MSX1 in T-ALL cell lines","pmids":["27322685"],"confidence":"Medium","gaps":["Direct PCGF5 occupancy at MSX1 not shown","Mechanism switching PCGF5 between repression and activation unresolved"]},{"year":2017,"claim":"Reconstituted the degradation mechanism, showing TRP120 itself is a HECT E3 ligase that polyubiquitinates PCGF5 via Nedd4L, explaining how the pathogen eliminates a host repressor.","evidence":"In vitro ubiquitination with purified TRP120 and E2 enzymes, HECT catalytic-site mutant, and Nedd4L siRNA knockdown","pmids":["28630068"],"confidence":"High","gaps":["Ubiquitin chain linkage type on PCGF5 not specified","Whether endogenous PCGF5 turnover uses this pathway outside infection unknown"]},{"year":2017,"claim":"Reassigned PCGF5 (with PCGF3) as a potential transcriptional activator through Tex10/p300, broadening its role beyond repression and into mesoderm specification.","evidence":"CRISPR knockout, proteomic interactome (MS), promoter occupancy ChIP, and differentiation assays in ES cells","pmids":["29054931"],"confidence":"High","gaps":["How PCGF5 toggles between activator and repressor not mechanistically resolved","PCGF5-specific vs PCGF3-shared contributions not fully separated"]},{"year":2018,"claim":"Placed PCGF5 causally in neural differentiation by showing its loss derepresses SMAD2/TGF-β signaling and blocks resolution of repressive marks at neural genes.","evidence":"CRISPR knockout in mESCs with RNA-seq, histone-mark ChIP-seq, and rescue","pmids":["29765032"],"confidence":"High","gaps":["Direct PCGF5 targets among SMAD2 pathway genes not enumerated","Composition of the relevant PRC1 variant at neural loci not defined"]},{"year":2018,"claim":"Showed the infection consequences of PCGF5 loss: TRP120-driven nuclear-to-vacuole redistribution and proteasomal degradation that disrupts PRC1 repression of HOX loci and favors bacterial growth.","evidence":"Co-IP, confocal IF, siRNA knockdown with infection readout, proteasome inhibition, and H2AK119ub1 ChIP","pmids":["29358333"],"confidence":"High","gaps":["Whether HOX derepression directly benefits the pathogen not established","Specific PCGF5-target genes among redistributed loci not isolated"]},{"year":2018,"claim":"Implicated PCGF5 in lineage exclusion and limb patterning, co-occupying SCL/RYBP target loci and contributing to a variant PRC1 that polarizes Meis2.","evidence":"Scl-null mouse model with RYBP/H2AK119ub1/H3K27me3 ChIP-seq, and mouse limb-bud genetic/modeling studies","pmids":["30560907","30190278"],"confidence":"Medium","gaps":["PCGF5-specific contribution inferred from co-occupancy rather than direct PCGF5 knockout","Functional redundancy with PCGF3 not dissected"]},{"year":2020,"claim":"Extended PCGF5's role across all germ layers, linking its loss to altered Nodal/Wnt/Notch signaling and shifted cardiomyocyte vs neural-ectodermal fate.","evidence":"CRISPR knockout mESCs with embryoid body differentiation and pathway-level gene expression","pmids":["32130724"],"confidence":"Medium","gaps":["Direct chromatin targets driving each signaling change not mapped","Single study, single lab"]},{"year":2024,"claim":"Defined a signaling mechanism for PCGF5 in neural stem cell fate via Notch1/Hes1-mediated suppression of Wnt3, validated across two model systems.","evidence":"siRNA knockdown/overexpression in P19 cells and zebrafish morpholino knockdown with marker and developmental readouts","pmids":["38533065"],"confidence":"Medium","gaps":["Whether PCGF5 acts directly at Notch1/Hes1/Wnt3 loci via PRC1 marks not shown","Single lab"]},{"year":2025,"claim":"Implicated PCGF5 in the earliest embryonic chromatin program, linking it to ZGA, noncanonical imprinting, and Xist-mediated X regulation.","evidence":"Morpholino knockdown in mouse preimplantation embryos with H3K27me3/H2AK119ub1 ChIP and expression analysis (preprint)","pmids":["bio_10.1101_2025.01.24.632300"],"confidence":"Medium","gaps":["Preprint, not yet peer-reviewed","Significance of the MT2C_Mm chimeric transcript unclear","Direct vs indirect effect on Xist region not separated"]},{"year":null,"claim":"How PCGF5 is switched between repressive (H2AK119ub1-depositing) and activating (Tex10/p300) modes at specific loci, and how its complex composition selects targets across distinct developmental contexts, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of PCGF5-containing variant PRC1","Determinants of activator-vs-repressor choice undefined","Comprehensive direct target map across cell types lacking"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[0,1,11]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[2,3]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,3,7,8]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[14,15]}],"pathway":[{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[0,2,3]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[1,11]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[0,1,13]}],"complexes":["non-canonical PRC1 (PRC1.5/variant PRC1)"],"partners":["RING1A/B","RYBP","AUTS2","TEX10","P300","TRP120","NEDD4L","WDR68/DCAF7"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q86SE9","full_name":"Polycomb group RING finger protein 5","aliases":["RING finger protein 159"],"length_aa":256,"mass_kda":29.7,"function":"Component of a Polycomb group (PcG) multiprotein PRC1-like complex, a complex class required to maintain the transcriptionally repressive state of many genes, including Hox genes, throughout development. PcG PRC1 complex acts via chromatin remodeling and modification of histones; it mediates monoubiquitination of histone H2A 'Lys-119', rendering chromatin heritably changed in its expressibility (PubMed:26151332). Within the PRC1-like complex, regulates RNF2 ubiquitin ligase activity (PubMed:26151332). Plays a redundant role with PCGF3 as part of a PRC1-like complex that mediates monoubiquitination of histone H2A 'Lys-119' on the X chromosome and is required for normal silencing of one copy of the X chromosome in XX females (By similarity)","subcellular_location":"Nucleus; Nucleus, nucleoplasm","url":"https://www.uniprot.org/uniprotkb/Q86SE9/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/PCGF5","classification":"Not Classified","n_dependent_lines":14,"n_total_lines":1208,"dependency_fraction":0.011589403973509934},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CSNK2B","stoichiometry":0.2},{"gene":"SNX9","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/PCGF5","total_profiled":1310},"omim":[{"mim_id":"617543","title":"POLYCOMB GROUP RING FINGER PROTEIN 3; PCGF3","url":"https://www.omim.org/entry/617543"},{"mim_id":"617407","title":"POLYCOMB GROUP RING FINGER PROTEIN 5; PCGF5","url":"https://www.omim.org/entry/617407"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PCGF5"},"hgnc":{"alias_symbol":["MGC16202"],"prev_symbol":["RNF159"]},"alphafold":{"accession":"Q86SE9","domains":[{"cath_id":"3.30.40.10","chopping":"8-79","consensus_level":"high","plddt":96.1397,"start":8,"end":79},{"cath_id":"3.10.20.90","chopping":"137-219_242-250","consensus_level":"high","plddt":86.2337,"start":137,"end":250}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86SE9","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q86SE9-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q86SE9-F1-predicted_aligned_error_v6.png","plddt_mean":80.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PCGF5","jax_strain_url":"https://www.jax.org/strain/search?query=PCGF5"},"sequence":{"accession":"Q86SE9","fasta_url":"https://rest.uniprot.org/uniprotkb/Q86SE9.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q86SE9/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86SE9"}},"corpus_meta":[{"pmid":"23533592","id":"PMC_23533592","title":"OstemiR: 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mESCs, RNA-seq, ChIP-seq, rescue experiments\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean KO with defined cellular phenotype, ChIP-seq for histone marks, pathway placement via SMAD2/TGF-β, multiple orthogonal methods in a single rigorous study\",\n      \"pmids\": [\"29765032\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"PCGF3 and PCGF5 function as transcriptional activators in ES cells through interaction with the pluripotency factor Tex10 and the co-activator p300; Pcgf3/5 deletion reduces Tex10 and p300 occupancy at target genes and globally reduces H2AK119ub1 levels; Pcgf3/5 are required for mesoderm differentiation.\",\n      \"method\": \"CRISPR/Cas9 knockout, RNA-seq, proteomic interactome (MS), ChIP/promoter occupancy analysis, in vitro and in vivo differentiation assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-IP/MS interactome, ChIP occupancy, KO phenotype, multiple orthogonal methods in one study\",\n      \"pmids\": [\"29054931\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Pcgf5 deletion in hematopoietic stem and progenitor cells (HSPCs) causes significant reduction in global H2AK119ub1 levels but does not impair HSPC self-renewal or repopulating capacity, indicating that Pcgf5-containing PRC1 functions as a histone modifier in vivo but its role in HSPCs is compensated by other PRC1-related complexes.\",\n      \"method\": \"Conditional Cre-ERT knockout in mice, competitive bone marrow transplantation, ChIP-seq for H2AK119ub1, flow cytometry\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO with in vivo competitive repopulation assay, ChIP-seq, multiple orthogonal readouts\",\n      \"pmids\": [\"27136092\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"During E. chaffeensis infection, the bacterial effector TRP120 interacts with PCGF5 (and other PCGF isoforms) in the nucleus early in infection; PCGF isoforms are redistributed from the nucleus to the ehrlichial vacuole and subsequently undergo proteasomal degradation; this disrupts PRC1-mediated H2AK119ub1 repressive marks and alters HOXB/HOXC gene transcription; siRNA knockdown of PCGF isoforms increases E. chaffeensis infection.\",\n      \"method\": \"Ectopic expression and co-immunoprecipitation of TRP120, confocal immunofluorescence microscopy, siRNA knockdown, proteasome inhibitor treatment, ChIP for H2AK119ub1\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — co-IP, siRNA KD with infection phenotype, ChIP, and live-imaging redistribution, multiple orthogonal methods\",\n      \"pmids\": [\"29358333\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"The E. chaffeensis effector TRP120 acts as a HECT E3 ubiquitin ligase that polyubiquitinates PCGF5, leading to reduced PCGF5 protein levels; this activity depends on Nedd4L, which also mediates TRP120 ubiquitination; Nedd4L knockdown reduces TRP120-Ub, decreases ehrlichial infection, and reduces PCGF5 recruitment to ehrlichial inclusions.\",\n      \"method\": \"In vitro ubiquitination assay with purified TRP120 and E2 enzymes, ectopic expression of HECT catalytic-site mutant, Nedd4L siRNA knockdown, immunoprecipitation\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstituted ubiquitination assay with catalytic-site mutagenesis confirmed in cells, replicated with siRNA knockdown\",\n      \"pmids\": [\"28630068\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"During blood specification, SCL/TAL1 directly activates expression of PCGF5 (along with RYBP) as part of a Polycomb-PRC1 co-repressor program that suppresses alternative cardiac/paraxial lineage gene expression; PCGF5 and RYBP co-occupy SCL target genes including cardiac/paraxial loci; reduction of Rybp expression mimics the Scl-null cardiac phenotype.\",\n      \"method\": \"Scl-null mouse model, RNA-seq, ChIP-seq for RYBP and H2AK119ub1/H3K27me3, genome-wide ChIP, genetic rescue (Eto2/Rybp knockdown)\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-seq and genetic epistasis in single study; PCGF5-specific mechanistic contribution is inferred from co-occupancy data rather than direct PCGF5 KO in this context\",\n      \"pmids\": [\"30560907\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"A variant PRC1 complex incorporating PCGF3 and PCGF5 represses Meis2 expression in the distal mouse forelimb bud; PcG factors and retinoic acid-related signals antagonize each other to polarize Meis2 expression along the proximal-distal axis.\",\n      \"method\": \"Mouse genetic models, mathematical modeling, in vivo gene expression analysis\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo mouse model with defined genetic pathway, but PCGF5-specific contribution inferred alongside PCGF3 with limited orthogonal mechanistic dissection of PCGF5 alone\",\n      \"pmids\": [\"30190278\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The E. chaffeensis TRP47 effector interacts with PCGF5; the amino-terminal truncated form of p47 containing tandem repeats interacts with PCGF5 but not with FYN, PTPN2, or CAP1, establishing that the TR domain of p47 is sufficient for PCGF5 interaction; interaction confirmed by co-immunoprecipitation and colocalization in HeLa cells.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, colocalization by confocal fluorescence microscopy in HeLa cells transfected with AcGFP1-p47\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal confirmation by yeast two-hybrid and co-IP with colocalization, domain-mapping experiment, single lab\",\n      \"pmids\": [\"19273555\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"The E. chaffeensis TRP120 effector interacts with PCGF5; the TR domain of TRP120 is sufficient for interaction with PCGF5 specifically, while other host targets require additional TRP120 domains; TRP120 and PCGF5 strongly colocalize in HeLa cells and near ehrlichial morulae.\",\n      \"method\": \"Yeast two-hybrid cotransformation confirmation, colocalization by fluorescence microscopy in HeLa cells\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — yeast two-hybrid and colocalization; domain mapping identifies TR domain as sufficient, replicated in Ehrlichia infection context across multiple papers\",\n      \"pmids\": [\"21859857\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"PCGF5 interacts exclusively with the long isoform of AUTS2 (not the short isoform), as identified by yeast two-hybrid screen; PCGF3 expression levels influence the ability of the long AUTS2 isoform to activate or repress transcription, placing PCGF5 in the long-isoform-specific AUTS2-PRC1 complex.\",\n      \"method\": \"Yeast two-hybrid screen, reporter transcriptional assays\",\n      \"journal\": \"Molecular psychiatry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — yeast two-hybrid only for PCGF5 interaction, single lab, no direct biochemical confirmation of PCGF5-AUTS2 complex reported in this abstract\",\n      \"pmids\": [\"30953002\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"SUMO pathway inhibition significantly reduced recruitment of PCGF5 to E. chaffeensis ehrlichial inclusions (TRP120-interacting protein), demonstrating that SUMO-dependent interactions are required for PCGF5 localization to the bacterial inclusion during infection.\",\n      \"method\": \"Small-molecule SUMO pathway inhibitor treatment, confocal colocalization microscopy, co-immunoprecipitation\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pharmacological perturbation with direct imaging readout in infection context, co-IP confirmation, single lab\",\n      \"pmids\": [\"25047847\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"In T-ALL cells, PCGF5 represses transcription of the NKL homeobox gene MSX1, while AUTS2 (as part of PRC1.5/PRC1 subtype 5) activates it; expression profiling and functional analyses demonstrate opposing activities of PCGF5 and AUTS2 on MSX1 transcription.\",\n      \"method\": \"Expression profiling, forced-expression experiments, pharmacological EZH2 inhibition, H3K27me3 ChIP analysis in T-ALL cell lines\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional KD/OE with defined transcriptional readout and ChIP, single lab, multiple methods\",\n      \"pmids\": [\"27322685\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Pcgf5 suppresses Wnt3 expression via activation of the Notch1/Hes1 signaling axis, thereby governing the differentiation fate of neural stem cells; knockdown of Pcgf5 in P19 cells decreases neuronal markers (Sox2, Zfp521, Pax6) while increasing pluripotency markers (Oct4, Nanog), and knockdown of pcgf5a by morpholino in zebrafish causes neurodevelopmental defects.\",\n      \"method\": \"siRNA knockdown and overexpression in P19 cells, zebrafish morpholino knockdown, qRT-PCR, in vivo neural marker analysis\",\n      \"journal\": \"Heliyon\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KD and OE with defined phenotypic readout in two model systems (P19 cells + zebrafish), pathway placement via Notch1/Hes1/Wnt3 axis, single lab\",\n      \"pmids\": [\"38533065\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Pcgf5 knockout in mESCs delays generation of the three germ layers (especially ectoderm), impairs epithelial-mesenchymal transition during embryoid body morphogenesis, differentially affects Nodal and Wnt signaling gene expression, and induces repression of Notch pathway genes leading to enhanced cardiomyocyte maturation and dampened ectodermal-neural differentiation.\",\n      \"method\": \"CRISPR/Cas9 KO mESCs, embryoid body differentiation protocol, gene expression analysis\",\n      \"journal\": \"Development, growth & differentiation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean CRISPR KO with defined developmental phenotypes and pathway-level gene expression analysis, single lab, single study\",\n      \"pmids\": [\"32130724\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Pcgf5 forms a chimeric transcript with MT2C_Mm (MERVL long terminal repeat) during zygotic genome activation (ZGA); Pcgf5 knockdown reduces H3K27me3 and H2AK119ub1 in mouse preimplantation embryos, upregulates ZGA genes and imprinting genes, and impairs H3K27me3 addition to the maternal Xist region, implicating Pcgf5 in noncanonical imprinting and Xist regulation.\",\n      \"method\": \"Morpholino knockdown in mouse embryos, ChIP for H3K27me3 and H2AK119ub1, developmental rate tracking, gene expression analysis\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean KD with ChIP readout and multiple phenotypic endpoints in preimplantation embryos; preprint, not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.01.24.632300\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PCGF5 is among a minority of Xist-recruited proteins that form Xist-seeded protein assemblies at the inactive X chromosome, placing it in the supramolecular assembly that drives X-chromosome inactivation.\",\n      \"method\": \"Protein assembly and localization analysis at the inactive X chromosome (described in the context of CIZ1-focused study)\",\n      \"journal\": \"Frontiers in cell and developmental biology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — PCGF5 listed as one of several proteins forming Xist-seeded assemblies; mechanistic detail for PCGF5 specifically is not elaborated in this abstract\",\n      \"pmids\": [\"38155839\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"WDR68/DCAF7 interacts with PCGF5 (and AUTS2) as identified by co-immunoprecipitation coupled with LC-MS, placing PCGF5 in the WDR68 interactome relevant to mouse embryonic development.\",\n      \"method\": \"Co-immunoprecipitation combined with liquid chromatography-mass spectrometry (Co-IP/LC-MS)\",\n      \"journal\": \"Journal of translational medicine\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single Co-IP/MS experiment identifying PCGF5 as WDR68 interactor; no functional follow-up specific to PCGF5 reported\",\n      \"pmids\": [\"40462101\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PCGF5 is a core subunit of non-canonical Polycomb Repressive Complex 1 (PRC1.5) that catalyzes H2AK119ub1 and maintains H3K27me3 at target loci; it functions as a context-dependent transcriptional regulator—repressing TGF-β/SMAD2 and alternative lineage genes while facilitating neural and mesodermal differentiation—through interactions with RING1A/B, RYBP, AUTS2, Tex10, and p300, and is targeted for proteasomal degradation by the bacterial E3 ubiquitin ligase TRP120 during Ehrlichia chaffeensis infection to disrupt PRC1-mediated host gene repression.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PCGF5 is a subunit of a variant (non-canonical) Polycomb Repressive Complex 1 that controls the histone modifications H2AK119ub1 and H3K27me3 to direct lineage choice during differentiation [#0, #2]. Loss of PCGF5 globally reduces H2AK119ub1 in vivo, establishing it as a bona fide effector of PRC1 histone-modifying activity [#2]. Its transcriptional output is context-dependent: in mouse ES cells PCGF5 represses the SMAD2/TGF-\\u03b2 pathway and resolves repressive marks around neural genes to permit neural differentiation [#0], yet together with PCGF3 it can act as a transcriptional activator through the pluripotency factor Tex10 and the co-activator p300 and is required for mesoderm differentiation [#1]. PCGF5 partitions cell fate during embryoid body and germ-layer formation, modulating Nodal, Wnt, and Notch signaling [#13], and governs neural stem cell fate by suppressing Wnt3 via the Notch1/Hes1 axis [#12]. Within these complexes PCGF5 partners with RYBP in an SCL/TAL1-driven program that silences alternative cardiac/paraxial lineage genes during blood specification [#5] and with the long isoform of AUTS2, with which it exerts opposing transcriptional effects on the homeobox target MSX1 [#11]. PCGF5 is also a host target hijacked during Ehrlichia chaffeensis infection: the bacterial effector TRP120 functions as a HECT E3 ubiquitin ligase that polyubiquitinates PCGF5 in a Nedd4L-dependent manner, driving its proteasomal degradation, redistribution to the ehrlichial vacuole, and loss of PRC1-mediated repression of HOX loci [#3, #4].\",\n  \"teleology\": [\n    {\n      \"year\": 2009,\n      \"claim\": \"Established the earliest physical link between PCGF5 and a pathogen effector, defining the tandem-repeat domain as the interaction module.\",\n      \"evidence\": \"Yeast two-hybrid, co-IP, and confocal colocalization of E. chaffeensis TRP47 with PCGF5 in HeLa cells\",\n      \"pmids\": [\"19273555\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of the interaction for PCGF5 or infection not tested\", \"No link to PCGF5's chromatin function established at this stage\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Identified a second Ehrlichia effector, TRP120, as a PCGF5-binding protein, showing its TR domain is specifically sufficient for the interaction.\",\n      \"evidence\": \"Yeast two-hybrid cotransformation and fluorescence colocalization near ehrlichial morulae in HeLa cells\",\n      \"pmids\": [\"21859857\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of PCGF5 recruitment unresolved\", \"No demonstration of effect on host transcription\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Showed that PCGF5 recruitment to the pathogen inclusion is SUMO-dependent, defining a post-translational requirement for its relocalization during infection.\",\n      \"evidence\": \"Small-molecule SUMO pathway inhibition with confocal colocalization and co-IP in infected cells\",\n      \"pmids\": [\"25047847\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct SUMO substrate (PCGF5 vs TRP120) not pinpointed\", \"Consequence for PCGF5 chromatin targets not measured\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Tested whether PCGF5 is required for its histone mark in vivo, revealing it is a global H2AK119ub1 modifier but functionally redundant in hematopoietic stem cells.\",\n      \"evidence\": \"Conditional Cre-ERT knockout in mice, competitive bone marrow transplantation, and H2AK119ub1 ChIP-seq\",\n      \"pmids\": [\"27136092\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of compensating PRC1-related complexes not defined\", \"Did not reveal a non-redundant lineage context\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Demonstrated context-specific repression by PCGF5 of a homeobox target, contrasting it with the activating activity of AUTS2 in the same complex subtype.\",\n      \"evidence\": \"Forced expression, EZH2 inhibition, and H3K27me3 ChIP on MSX1 in T-ALL cell lines\",\n      \"pmids\": [\"27322685\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct PCGF5 occupancy at MSX1 not shown\", \"Mechanism switching PCGF5 between repression and activation unresolved\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Reconstituted the degradation mechanism, showing TRP120 itself is a HECT E3 ligase that polyubiquitinates PCGF5 via Nedd4L, explaining how the pathogen eliminates a host repressor.\",\n      \"evidence\": \"In vitro ubiquitination with purified TRP120 and E2 enzymes, HECT catalytic-site mutant, and Nedd4L siRNA knockdown\",\n      \"pmids\": [\"28630068\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Ubiquitin chain linkage type on PCGF5 not specified\", \"Whether endogenous PCGF5 turnover uses this pathway outside infection unknown\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Reassigned PCGF5 (with PCGF3) as a potential transcriptional activator through Tex10/p300, broadening its role beyond repression and into mesoderm specification.\",\n      \"evidence\": \"CRISPR knockout, proteomic interactome (MS), promoter occupancy ChIP, and differentiation assays in ES cells\",\n      \"pmids\": [\"29054931\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How PCGF5 toggles between activator and repressor not mechanistically resolved\", \"PCGF5-specific vs PCGF3-shared contributions not fully separated\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Placed PCGF5 causally in neural differentiation by showing its loss derepresses SMAD2/TGF-\\u03b2 signaling and blocks resolution of repressive marks at neural genes.\",\n      \"evidence\": \"CRISPR knockout in mESCs with RNA-seq, histone-mark ChIP-seq, and rescue\",\n      \"pmids\": [\"29765032\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct PCGF5 targets among SMAD2 pathway genes not enumerated\", \"Composition of the relevant PRC1 variant at neural loci not defined\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Showed the infection consequences of PCGF5 loss: TRP120-driven nuclear-to-vacuole redistribution and proteasomal degradation that disrupts PRC1 repression of HOX loci and favors bacterial growth.\",\n      \"evidence\": \"Co-IP, confocal IF, siRNA knockdown with infection readout, proteasome inhibition, and H2AK119ub1 ChIP\",\n      \"pmids\": [\"29358333\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether HOX derepression directly benefits the pathogen not established\", \"Specific PCGF5-target genes among redistributed loci not isolated\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Implicated PCGF5 in lineage exclusion and limb patterning, co-occupying SCL/RYBP target loci and contributing to a variant PRC1 that polarizes Meis2.\",\n      \"evidence\": \"Scl-null mouse model with RYBP/H2AK119ub1/H3K27me3 ChIP-seq, and mouse limb-bud genetic/modeling studies\",\n      \"pmids\": [\"30560907\", \"30190278\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"PCGF5-specific contribution inferred from co-occupancy rather than direct PCGF5 knockout\", \"Functional redundancy with PCGF3 not dissected\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Extended PCGF5's role across all germ layers, linking its loss to altered Nodal/Wnt/Notch signaling and shifted cardiomyocyte vs neural-ectodermal fate.\",\n      \"evidence\": \"CRISPR knockout mESCs with embryoid body differentiation and pathway-level gene expression\",\n      \"pmids\": [\"32130724\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct chromatin targets driving each signaling change not mapped\", \"Single study, single lab\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined a signaling mechanism for PCGF5 in neural stem cell fate via Notch1/Hes1-mediated suppression of Wnt3, validated across two model systems.\",\n      \"evidence\": \"siRNA knockdown/overexpression in P19 cells and zebrafish morpholino knockdown with marker and developmental readouts\",\n      \"pmids\": [\"38533065\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether PCGF5 acts directly at Notch1/Hes1/Wnt3 loci via PRC1 marks not shown\", \"Single lab\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Implicated PCGF5 in the earliest embryonic chromatin program, linking it to ZGA, noncanonical imprinting, and Xist-mediated X regulation.\",\n      \"evidence\": \"Morpholino knockdown in mouse preimplantation embryos with H3K27me3/H2AK119ub1 ChIP and expression analysis (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.01.24.632300\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not yet peer-reviewed\", \"Significance of the MT2C_Mm chimeric transcript unclear\", \"Direct vs indirect effect on Xist region not separated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How PCGF5 is switched between repressive (H2AK119ub1-depositing) and activating (Tex10/p300) modes at specific loci, and how its complex composition selects targets across distinct developmental contexts, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of PCGF5-containing variant PRC1\", \"Determinants of activator-vs-repressor choice undefined\", \"Comprehensive direct target map across cell types lacking\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [0, 1, 11]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [2, 3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 3, 7, 8]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [14, 15]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [0, 2, 3]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [1, 11]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [0, 1, 13]}\n    ],\n    \"complexes\": [\"non-canonical PRC1 (PRC1.5/variant PRC1)\"],\n    \"partners\": [\"RING1A/B\", \"RYBP\", \"AUTS2\", \"Tex10\", \"p300\", \"TRP120\", \"Nedd4L\", \"WDR68/DCAF7\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}