{"gene":"PPP2R3C","run_date":"2026-06-10T06:43:35","timeline":{"discoveries":[{"year":2002,"finding":"G5PR (PPP2R3C) was identified as a GANP-associated molecule via yeast two-hybrid screening. Pull-down assays demonstrated that G5PR associates with protein phosphatase 2A (PP2A; the A/PR65 and catalytic C subunits) and with protein phosphatase 5 (PP5) through its TPR domain. The G5PR-associated complex had phosphatase activity on casein, histone H1, and MCM3 in vitro, though addition of G5PR alone did not stimulate or inhibit PP5 or PP2A activities. G5PR cellular localization varied with cell cycle phase: nuclear during prophase, peri-chromatin during mitosis, and cytoplasmic after cell division.","method":"Yeast two-hybrid screening, in vivo co-immunoprecipitation in transfectants, pull-down assays, in vitro phosphatase activity assays, immunofluorescence localization","journal":"Genes to cells : devoted to molecular & cellular mechanisms","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal pull-down and in vitro activity assays in a single lab with multiple orthogonal methods","pmids":["12167160"],"is_preprint":false},{"year":2005,"finding":"Conditional knockout of G5pr in B cells (CD19-Cre) showed that G5PR is required for BCR-mediated proliferation and prevention of activation-induced cell death (AICD) in mature B cells. G5pr−/− B cells had increased mitochondrial membrane depolarization, enhanced JNK activation, and elevated Bim activation after BCR cross-linking, while Erk, NF-κB, cyclin D2, and Akt activation were normal.","method":"Conditional gene knockout (CD19-Cre), in vitro proliferation assays, flow cytometry, western blotting for signaling intermediates","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional KO with defined cellular phenotype and multiple signaling readouts, replicated across multiple assays in one rigorous study","pmids":["16129705"],"is_preprint":false},{"year":2005,"finding":"BCR cross-linking induced G5PR (PPP2R3C) transcription selectively in AICD-resistant mature splenic IgM-lo IgD-hi B cells but not in AICD-susceptible immature B cells. G5pr cDNA transfection protected the immature B-cell line WEHI-231 from BCR-mediated AICD, and lack of G5PR upregulation correlated with prolonged JNK activation.","method":"RT-PCR/northern analysis of B-cell subsets, cDNA transfection rescue experiment, JNK activation assays","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — transcription analysis plus cDNA rescue, single lab, two orthogonal methods","pmids":["16343422"],"is_preprint":false},{"year":2007,"finding":"T-cell-specific G5PR knockout mice displayed thymic atrophy and ~10-fold reduction in CD4/CD8 double-positive (DP) thymocytes with few mature single-positive cells. G5pr−/− thymocytes showed normal DN-to-DP transition but increased apoptosis at the DP stage, associated with hyper-activation of JNK and Caspase-3 and augmented FasL expression, but no change in Bim activation, demonstrating that G5PR controls a JNK-Caspase-3 apoptotic pathway specific to thymocytes.","method":"T-cell-specific conditional knockout, flow cytometry, apoptosis assays, western blotting for JNK, Caspase-3, Bim, FasL","journal":"Molecular immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional KO with defined cellular phenotype, multiple orthogonal signaling readouts, single lab but rigorous","pmids":["18022237"],"is_preprint":false},{"year":2011,"finding":"G4-1 (PPP2R3C) physically interacts with IKKβ in a manner dependent on IKKβ kinase activity. The serine-rich C-terminal domain of IKKβ (containing seven autophosphorylated serines) is required for G4-1 binding; mutating these serines to alanine abolished G4-1 binding and rendered IKKβ more potent at activating NF-κB. G4-1 knockdown enhanced TNFα-induced NF-κB activity. G4-1 functions as an adaptor that recruits PP5 to the phosphorylated C-terminus of activated IKKβ to down-regulate IKKβ activity; knockdown of PP5 abolished the inhibitory activity of G4-1 on NF-κB activation.","method":"Co-immunoprecipitation, domain-mapping mutagenesis, siRNA knockdown, NF-κB reporter assays, TNFα stimulation","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP with mutagenesis, siRNA validation of functional outcome, multiple orthogonal methods in single lab","pmids":["20925653"],"is_preprint":false},{"year":2012,"finding":"G5PR (PPP2R3C) is upregulated in Ki67-negative centrocytes at germinal centers and in mature GC B cells after immunization. Transgenic overexpression of G5PR led to augmented GC B cell generation via increase in non-antigen-specific B cells, impaired affinity maturation, suppression of late-phase JNK activation, and rescue of B-1a cells from AICD in vitro. Aged female G5PR-transgenic mice developed peritoneal B-1a cell expansion and autoantibody production.","method":"Transgenic mouse model, immunohistochemistry, flow cytometry, in vitro AICD assays, JNK phosphorylation assays, anti-NP antibody affinity measurement","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"High","confidence_rationale":"Tier 2 / Strong — transgenic gain-of-function with multiple cellular and molecular phenotypes, replicated across multiple assays in one study","pmids":["22753944"],"is_preprint":false},{"year":2013,"finding":"PPP2R3C was identified as a binding candidate for P-glycoprotein (ABCB1) by immunoprecipitation-western blotting; PP5 and PPP2R3C co-precipitated with P-gp but PP2A did not. The PP5/PPP2R3C complex dephosphorylated PKA/PKC-mediated phosphorylation of P-gp. Knockdown of PP5 and/or PPP2R3C increased P-gp expression and reduced sensitivity to vincristine and doxorubicin.","method":"Co-immunoprecipitation, western blotting, siRNA knockdown, in vitro dephosphorylation assay, cytotoxicity assay","journal":"Cancer letters","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus functional dephosphorylation assay plus siRNA phenotype, single lab with multiple methods","pmids":["24333728"],"is_preprint":false},{"year":2015,"finding":"G5PR overexpression in B1a cells suppressed BCR-mediated JNK signaling and drove differentiation of peritoneal B1a cells into IgM and IgG autoantibody-secreting plasmablasts in vitro. JNK inhibitor SP600125 recapitulated this effect in wild-type B1a cells, establishing that G5PR-mediated JNK suppression promotes B1a-to-plasmablast differentiation.","method":"G5PR-transgenic mouse B1a cell isolation, iGB culture system with IL-4/CD40L/BAFF, JNK inhibitor treatment, ELISA for autoantibody secretion, flow cytometry","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — transgenic gain-of-function combined with pharmacological validation, single lab","pmids":["25601926"],"is_preprint":false},{"year":2019,"finding":"Homozygous missense variants in PPP2R3C (p.L103P, p.L193S, p.F350S) cause 46,XY complete gonadal dysgenesis. Immunohistochemistry of dysgenetic gonads from patients showed decreased SOX9-phosphoprotein expression, implicating PPP2R3C in SOX9 phospho-signaling during testis development. Heterozygous males showed abnormal sperm morphology and impaired fertility.","method":"Exome/Sanger sequencing of patient cohort, immunohistochemistry for phospho-SOX9 in gonadal tissue","journal":"European journal of endocrinology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — human genetic variants with IHC molecular readout (phospho-SOX9), replicated across multiple families but no in vitro reconstitution","pmids":["30893644"],"is_preprint":false},{"year":2021,"finding":"Homozygous PPP2R3C p.L193S variant causes broad-spectrum gonadal dysgenesis in both 46,XY and 46,XX individuals. CRISPR/Cas9-generated homozygous Ppp2r3c knockout mice died during early embryogenesis (at or before 7.5 dpc), demonstrating that Ppp2r3c is essential for embryonic viability in mice.","method":"Sanger sequencing of patients, CRISPR/Cas9 knockout mice with timed embryo inspections","journal":"European journal of endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR knockout with defined embryonic lethal phenotype, confirmed by timed embryo inspection across multiple time points","pmids":["34714774"],"is_preprint":false},{"year":2024,"finding":"PPP2R3C is a distal centriole protein that localizes to centrosomes and functionally partners with centriolar proteins CEP350 and FOP. PPP2R3C counteracts the kinase activity of MAP3K1 at centrosomes: MAP3K1 knockout suppresses growth defects caused by PPP2R3C inactivation, and the two have opposing effects on basal and microtubule stress-induced JNK signaling. A disease-associated PPP2R3C variant is defective in centriolar localization and FOP binding. Acute MAP3K1 overexpression caused rapid centriole disintegration, phenocopying PPP2R3C loss.","method":"Systems genetics (functional genomic analyses), immunofluorescence/microscopy for centriolar localization, genetic epistasis (MAP3K1 KO suppression), JNK signaling assays, co-localization/binding studies with FOP and CEP350, disease variant analysis","journal":"Current biology : CB","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods including localization, genetic epistasis, kinase-phosphatase opposing activity assays, and disease-variant binding defect, replicated between preprint and peer-reviewed publication","pmids":["39317195","38617270"],"is_preprint":false},{"year":2024,"finding":"PPP2R3C (B″gamma subunit of PP2A) interacts with Gli proteins and acts as a positive regulator of Hedgehog signaling. PPP2R3C disruption reduced expression of Gli1/2 and Hh target genes upon pathway activation and reduced growth of a Hh-dependent medulloblastoma cell line. An antagonistic relationship was established between PPP2R3C and MEKK1 kinase in regulating Gli protein phosphorylation.","method":"Co-immunoprecipitation (PPP2R3C-Gli interaction), siRNA/CRISPR knockdown with Hh pathway reporter assays and target gene qPCR, cell proliferation assays, phosphorylation analysis of Gli","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus loss-of-function with multiple pathway readouts, single lab with orthogonal methods","pmids":["39173855"],"is_preprint":false}],"current_model":"PPP2R3C (G5PR/G4-1) is a regulatory subunit that bridges PP2A and PP5 phosphatases to multiple signaling complexes: it localizes to distal centrioles where it counteracts MAP3K1 kinase activity to maintain centrosome integrity and suppress JNK signaling; in immune cells it recruits PP5 to phosphorylated IKKβ to dampen NF-κB activation, regulates BCR-mediated JNK-Caspase-3 apoptosis in B cells and thymocytes, and promotes B-cell survival by suppressing late-phase JNK and Bim activation; it also dephosphorylates P-glycoprotein via a PP5/PPP2R3C complex to downregulate ABCB1 function, interacts with Gli transcription factors to positively regulate Hedgehog signaling, and its loss-of-function causes embryonic lethality in mice and syndromic 46,XY/XX gonadal dysgenesis in humans through impaired SOX9 phospho-signaling."},"narrative":{"mechanistic_narrative":"PPP2R3C (G5PR/G4-1) is a non-catalytic regulatory/adaptor subunit that bridges the serine/threonine phosphatases PP2A and PP5 to specific phosphorylated targets, thereby restraining stress and kinase signaling across immune, developmental, and centrosomal contexts [PMID:12167160, PMID:20925653]. It associates with the PP2A A/C subunits and with PP5 through a TPR-domain interaction, forming a complex with phosphatase activity in vitro [PMID:12167160]. A recurring theme of its biology is suppression of JNK signaling: conditional deletion in B cells and thymocytes causes hyperactivation of JNK and downstream apoptotic effectors (Bim in B cells; Caspase-3 and FasL in thymocytes), driving activation-induced and developmental cell death, whereas its induction or overexpression dampens late-phase JNK to promote B-cell survival and differentiation [PMID:16129705, PMID:18022237, PMID:22753944]. As an adaptor it recruits PP5 to substrate phosphosites — to the autophosphorylated serine-rich C-terminus of activated IKKβ to down-regulate NF-κB [PMID:20925653], and to phosphorylated P-glycoprotein (ABCB1) to reduce its expression and drug efflux activity [PMID:24333728]. At the distal centriole it partners with CEP350 and FOP and counteracts the kinase MAP3K1 to maintain centrosome integrity and limit JNK signaling, with a disease variant defective in centriolar localization and FOP binding [PMID:39317195, PMID:38617270]; it analogously antagonizes MEKK1 to control Gli phosphorylation and positively regulates Hedgehog target-gene expression [PMID:39173855]. Homozygous missense variants in PPP2R3C cause syndromic 46,XY/XX gonadal dysgenesis with reduced phospho-SOX9 in dysgenetic gonads, and complete loss is embryonic lethal in mice [PMID:30893644, PMID:34714774].","teleology":[{"year":2002,"claim":"Established the founding biochemical identity of PPP2R3C as a phosphatase-associated subunit, answering what enzymatic machinery it engages.","evidence":"Yeast two-hybrid, reciprocal pull-downs, and in vitro phosphatase assays in transfectants showing TPR-mediated association with PP2A (A/C subunits) and PP5","pmids":["12167160"],"confidence":"Medium","gaps":["G5PR alone neither stimulated nor inhibited PP2A/PP5 activity, leaving its regulatory mechanism on phosphatase activity undefined","no physiological substrate identified at this stage","cell-cycle-dependent localization not linked to a function"]},{"year":2005,"claim":"Defined a physiological requirement for PPP2R3C in restraining JNK-driven apoptosis, showing the subunit has a discrete cellular survival function rather than a generic housekeeping role.","evidence":"B-cell conditional knockout (CD19-Cre) with proliferation/apoptosis assays and signaling western blots; plus transcriptional induction analysis and cDNA rescue in WEHI-231 cells","pmids":["16129705","16343422"],"confidence":"High","gaps":["did not establish which phosphatase (PP2A vs PP5) mediates JNK suppression","direct dephosphorylation target in the JNK pathway not identified","selectivity for JNK over Erk/NF-κB/Akt mechanistically unexplained"]},{"year":2007,"claim":"Showed the JNK-restraining function operates in a cell-type-specific manner, controlling a JNK-Caspase-3 apoptotic pathway in thymocytes distinct from the Bim-dependent route in B cells.","evidence":"T-cell-specific conditional knockout with flow cytometry, apoptosis assays, and western blotting for JNK, Caspase-3, Bim, FasL","pmids":["18022237"],"confidence":"High","gaps":["why Bim is engaged in B cells but not thymocytes is unresolved","molecular substrate upstream of JNK not defined","no biochemical reconstitution of the phosphatase-JNK axis"]},{"year":2011,"claim":"Resolved the molecular adaptor mechanism, demonstrating PPP2R3C bridges PP5 to a phosphorylated substrate to terminate signaling.","evidence":"Co-IP with domain-mapping mutagenesis of IKKβ phospho-serines, siRNA knockdown of G4-1 and PP5, and NF-κB reporter assays under TNFα","pmids":["20925653"],"confidence":"High","gaps":["structural basis of phospho-IKKβ recognition not determined","whether the same adaptor logic explains JNK regulation untested","in vivo relevance of the NF-κB axis not addressed"]},{"year":2012,"claim":"Demonstrated gain-of-function consequences in vivo, linking PPP2R3C-mediated JNK suppression to B-cell survival, impaired affinity maturation, and autoimmunity.","evidence":"Transgenic overexpression mouse with immunohistochemistry, flow cytometry, in vitro AICD and JNK assays, and antibody affinity measurement","pmids":["22753944"],"confidence":"High","gaps":["mechanism connecting JNK suppression to autoantibody production not dissected","phosphatase substrate(s) controlling late-phase JNK unknown"]},{"year":2013,"claim":"Extended the PP5-adaptor role beyond immune signaling, identifying P-glycoprotein as a substrate whose dephosphorylation modulates multidrug resistance.","evidence":"Co-IP, in vitro dephosphorylation of PKA/PKC-phosphorylated P-gp, siRNA knockdown with vincristine/doxorubicin cytotoxicity assays","pmids":["24333728"],"confidence":"Medium","gaps":["specific phospho-residues on P-gp dephosphorylated not mapped","single lab without reciprocal in vivo validation","PP2A excluded but PP5 contribution not quantitatively separated from PPP2R3C"]},{"year":2015,"claim":"Causally linked PPP2R3C-driven JNK suppression to B1a-cell-to-plasmablast differentiation using pharmacological phenocopy.","evidence":"Transgenic B1a-cell culture with JNK inhibitor SP600125 recapitulation, ELISA for autoantibody, flow cytometry","pmids":["25601926"],"confidence":"Medium","gaps":["direct phosphatase substrate in B1a JNK pathway unidentified","single-lab gain-of-function system"]},{"year":2019,"claim":"Established a human Mendelian disease link, implicating PPP2R3C in SOX9 phospho-signaling during testis development.","evidence":"Exome/Sanger sequencing of a patient cohort with homozygous missense variants plus phospho-SOX9 immunohistochemistry of dysgenetic gonads","pmids":["30893644"],"confidence":"Medium","gaps":["no in vitro reconstitution of variant effect on phosphatase function","direct phosphatase-SOX9 biochemical relationship not demonstrated","how each variant impairs the PP2A/PP5 complex unknown"]},{"year":2021,"claim":"Broadened the disease spectrum to both 46,XY and 46,XX dysgenesis and proved PPP2R3C is essential for embryonic viability.","evidence":"Sanger sequencing of patients with the recurrent p.L193S variant and CRISPR/Cas9 knockout mice with timed embryo inspection","pmids":["34714774"],"confidence":"Medium","gaps":["embryonic lethality precludes tissue-specific developmental mechanism","molecular cause of early lethality (before 7.5 dpc) not defined"]},{"year":2024,"claim":"Defined a subcellular site and antagonist for PPP2R3C function, placing it at the distal centriole where it opposes MAP3K1 to preserve centrosome integrity, and identifying a parallel Gli/Hedgehog regulatory role.","evidence":"Functional genomics, centriolar immunofluorescence, genetic epistasis (MAP3K1 KO suppression), JNK assays, FOP/CEP350 binding, and disease-variant localization defect; plus Co-IP and Hh reporter/qPCR/proliferation assays for the Gli axis","pmids":["39317195","38617270","39173855"],"confidence":"High","gaps":["whether PP2A or PP5 catalytic activity executes MAP3K1/Gli dephosphorylation at the centriole unresolved","direct phospho-substrate dephosphorylated to counter MAP3K1 not identified","link between centriolar function and gonadal/SOX9 phenotype not established"]},{"year":null,"claim":"It remains unresolved how PPP2R3C selects between its PP2A and PP5 catalytic partners for each substrate and how a single adaptor coordinates JNK, NF-κB, Hedgehog, centrosomal, and SOX9 outputs.","evidence":"","pmids":[],"confidence":"Medium","gaps":["no structural model of substrate-specific phosphatase targeting","direct catalytic substrate for the developmental/SOX9 phenotype unidentified","unifying biochemical logic across contexts undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,4,6]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,4,11]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[4,6]}],"localization":[{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[10]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[0]}],"pathway":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[4,6]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[4,11]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[1,3,5]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[1,3]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[8,9]},{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[10]}],"complexes":["PP2A holoenzyme (B''gamma regulatory subunit)","PP5/PPP2R3C phosphatase complex"],"partners":["PPP2CA","PPP5C","IKBKB","ABCB1","MAP3K1","FOP","CEP350","GLI"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q969Q6","full_name":"Serine/threonine-protein phosphatase 2A regulatory subunit B'' subunit gamma","aliases":["Protein phosphatase subunit G5PR","Rhabdomyosarcoma antigen MU-RMS-40.6A/6C"],"length_aa":453,"mass_kda":53.3,"function":"May regulate MCM3AP phosphorylation through phosphatase recruitment (By similarity). May act as a negative regulator of ABCB1 expression and function through the dephosphorylation of ABCB1 by TFPI2/PPP2R3C complex (PubMed:24333728). May play a role in the activation-induced cell death of B-cells (By similarity)","subcellular_location":"Nucleus; Cytoplasm","url":"https://www.uniprot.org/uniprotkb/Q969Q6/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/PPP2R3C","classification":"Common Essential","n_dependent_lines":902,"n_total_lines":1208,"dependency_fraction":0.7466887417218543},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"PPP2CA","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/PPP2R3C","total_profiled":1310},"omim":[{"mim_id":"618420","title":"SPERMATOGENIC FAILURE 36; SPGF36","url":"https://www.omim.org/entry/618420"},{"mim_id":"618419","title":"MYOECTODERMAL GONADAL DYSGENESIS SYNDROME; MEGD","url":"https://www.omim.org/entry/618419"},{"mim_id":"615902","title":"PROTEIN PHOSPHATASE 2, REGULATORY SUBUNIT B-DOUBLE PRIME, GAMMA; PPP2R3C","url":"https://www.omim.org/entry/615902"},{"mim_id":"603294","title":"MINICHROMOSOME MAINTENANCE 3-ASSOCIATED PROTEIN; MCM3AP","url":"https://www.omim.org/entry/603294"},{"mim_id":"602693","title":"MINICHROMOSOME MAINTENANCE COMPLEX COMPONENT 3; MCM3","url":"https://www.omim.org/entry/602693"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Nuclear bodies","reliability":"Additional"},{"location":"Golgi apparatus","reliability":"Additional"},{"location":"Actin filaments","reliability":"Additional"},{"location":"Primary cilium","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PPP2R3C"},"hgnc":{"alias_symbol":["FLJ20644","G4-1","G5PR"],"prev_symbol":["C14orf10"]},"alphafold":{"accession":"Q969Q6","domains":[{"cath_id":"1.10.238","chopping":"68-180","consensus_level":"medium","plddt":92.2158,"start":68,"end":180},{"cath_id":"1.10.238.220","chopping":"185-274","consensus_level":"high","plddt":95.2989,"start":185,"end":274},{"cath_id":"1.10.238.10","chopping":"293-436","consensus_level":"high","plddt":95.9851,"start":293,"end":436}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q969Q6","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q969Q6-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q969Q6-F1-predicted_aligned_error_v6.png","plddt_mean":89.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PPP2R3C","jax_strain_url":"https://www.jax.org/strain/search?query=PPP2R3C"},"sequence":{"accession":"Q969Q6","fasta_url":"https://rest.uniprot.org/uniprotkb/Q969Q6.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q969Q6/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q969Q6"}},"corpus_meta":[{"pmid":"2535250","id":"PMC_2535250","title":"Characterization 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peritoneal B1a cells.","date":"2015","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/25601926","citation_count":5,"is_preprint":false},{"pmid":"34714774","id":"PMC_34714774","title":"Broad-spectrum XX and XY gonadal dysgenesis in patients with a homozygous L193S variant in PPP2R3C.","date":"2021","source":"European journal of endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/34714774","citation_count":5,"is_preprint":false},{"pmid":"8711428","id":"PMC_8711428","title":"Differential effect of the activation of protein kinase A on the protein synthesis and secretion in the T-helper 2 cell line D10.G4.1.","date":"1996","source":"Scandinavian journal of immunology","url":"https://pubmed.ncbi.nlm.nih.gov/8711428","citation_count":4,"is_preprint":false},{"pmid":"8495978","id":"PMC_8495978","title":"The I-Ab-restricted alloresponse of D10.G4.1 T cells is based on the recognition of an endogenous peptide.","date":"1993","source":"Immunology","url":"https://pubmed.ncbi.nlm.nih.gov/8495978","citation_count":4,"is_preprint":false},{"pmid":"39317195","id":"PMC_39317195","title":"A disease-associated PPP2R3C-MAP3K1 phospho-regulatory module controls centrosome function.","date":"2024","source":"Current biology : CB","url":"https://pubmed.ncbi.nlm.nih.gov/39317195","citation_count":2,"is_preprint":false},{"pmid":"39173855","id":"PMC_39173855","title":"PP2A phosphatase regulatory subunit PPP2R3C is a new positive regulator of the hedgehog signaling pathway.","date":"2024","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/39173855","citation_count":2,"is_preprint":false},{"pmid":"8419473","id":"PMC_8419473","title":"Enhanced IL-4-mediated D10.G4.1 proliferation with suboptimal concentrations of anti-IL-4 receptor monoclonal antibodies.","date":"1993","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/8419473","citation_count":2,"is_preprint":false},{"pmid":"38617270","id":"PMC_38617270","title":"A disease-associated PPP2R3C-MAP3K1 phospho-regulatory module controls centrosome function.","date":"2024","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38617270","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.08.02.606355","title":"Integrated Single-Cell Multiomic Profiling of Caudate Nucleus Suggests Key Mechanisms in Alcohol Use Disorder","date":"2024-08-06","source":"bioRxiv","url":"https://doi.org/10.1101/2024.08.02.606355","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":14141,"output_tokens":3752,"usd":0.049351,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11405,"output_tokens":4142,"usd":0.080287,"stage2_stop_reason":"end_turn"},"total_usd":0.129638,"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\": 2002,\n      \"finding\": \"G5PR (PPP2R3C) was identified as a GANP-associated molecule via yeast two-hybrid screening. Pull-down assays demonstrated that G5PR associates with protein phosphatase 2A (PP2A; the A/PR65 and catalytic C subunits) and with protein phosphatase 5 (PP5) through its TPR domain. The G5PR-associated complex had phosphatase activity on casein, histone H1, and MCM3 in vitro, though addition of G5PR alone did not stimulate or inhibit PP5 or PP2A activities. G5PR cellular localization varied with cell cycle phase: nuclear during prophase, peri-chromatin during mitosis, and cytoplasmic after cell division.\",\n      \"method\": \"Yeast two-hybrid screening, in vivo co-immunoprecipitation in transfectants, pull-down assays, in vitro phosphatase activity assays, immunofluorescence localization\",\n      \"journal\": \"Genes to cells : devoted to molecular & cellular mechanisms\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal pull-down and in vitro activity assays in a single lab with multiple orthogonal methods\",\n      \"pmids\": [\"12167160\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Conditional knockout of G5pr in B cells (CD19-Cre) showed that G5PR is required for BCR-mediated proliferation and prevention of activation-induced cell death (AICD) in mature B cells. G5pr−/− B cells had increased mitochondrial membrane depolarization, enhanced JNK activation, and elevated Bim activation after BCR cross-linking, while Erk, NF-κB, cyclin D2, and Akt activation were normal.\",\n      \"method\": \"Conditional gene knockout (CD19-Cre), in vitro proliferation assays, flow cytometry, western blotting for signaling intermediates\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional KO with defined cellular phenotype and multiple signaling readouts, replicated across multiple assays in one rigorous study\",\n      \"pmids\": [\"16129705\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"BCR cross-linking induced G5PR (PPP2R3C) transcription selectively in AICD-resistant mature splenic IgM-lo IgD-hi B cells but not in AICD-susceptible immature B cells. G5pr cDNA transfection protected the immature B-cell line WEHI-231 from BCR-mediated AICD, and lack of G5PR upregulation correlated with prolonged JNK activation.\",\n      \"method\": \"RT-PCR/northern analysis of B-cell subsets, cDNA transfection rescue experiment, JNK activation assays\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — transcription analysis plus cDNA rescue, single lab, two orthogonal methods\",\n      \"pmids\": [\"16343422\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"T-cell-specific G5PR knockout mice displayed thymic atrophy and ~10-fold reduction in CD4/CD8 double-positive (DP) thymocytes with few mature single-positive cells. G5pr−/− thymocytes showed normal DN-to-DP transition but increased apoptosis at the DP stage, associated with hyper-activation of JNK and Caspase-3 and augmented FasL expression, but no change in Bim activation, demonstrating that G5PR controls a JNK-Caspase-3 apoptotic pathway specific to thymocytes.\",\n      \"method\": \"T-cell-specific conditional knockout, flow cytometry, apoptosis assays, western blotting for JNK, Caspase-3, Bim, FasL\",\n      \"journal\": \"Molecular immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional KO with defined cellular phenotype, multiple orthogonal signaling readouts, single lab but rigorous\",\n      \"pmids\": [\"18022237\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"G4-1 (PPP2R3C) physically interacts with IKKβ in a manner dependent on IKKβ kinase activity. The serine-rich C-terminal domain of IKKβ (containing seven autophosphorylated serines) is required for G4-1 binding; mutating these serines to alanine abolished G4-1 binding and rendered IKKβ more potent at activating NF-κB. G4-1 knockdown enhanced TNFα-induced NF-κB activity. G4-1 functions as an adaptor that recruits PP5 to the phosphorylated C-terminus of activated IKKβ to down-regulate IKKβ activity; knockdown of PP5 abolished the inhibitory activity of G4-1 on NF-κB activation.\",\n      \"method\": \"Co-immunoprecipitation, domain-mapping mutagenesis, siRNA knockdown, NF-κB reporter assays, TNFα stimulation\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP with mutagenesis, siRNA validation of functional outcome, multiple orthogonal methods in single lab\",\n      \"pmids\": [\"20925653\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"G5PR (PPP2R3C) is upregulated in Ki67-negative centrocytes at germinal centers and in mature GC B cells after immunization. Transgenic overexpression of G5PR led to augmented GC B cell generation via increase in non-antigen-specific B cells, impaired affinity maturation, suppression of late-phase JNK activation, and rescue of B-1a cells from AICD in vitro. Aged female G5PR-transgenic mice developed peritoneal B-1a cell expansion and autoantibody production.\",\n      \"method\": \"Transgenic mouse model, immunohistochemistry, flow cytometry, in vitro AICD assays, JNK phosphorylation assays, anti-NP antibody affinity measurement\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — transgenic gain-of-function with multiple cellular and molecular phenotypes, replicated across multiple assays in one study\",\n      \"pmids\": [\"22753944\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"PPP2R3C was identified as a binding candidate for P-glycoprotein (ABCB1) by immunoprecipitation-western blotting; PP5 and PPP2R3C co-precipitated with P-gp but PP2A did not. The PP5/PPP2R3C complex dephosphorylated PKA/PKC-mediated phosphorylation of P-gp. Knockdown of PP5 and/or PPP2R3C increased P-gp expression and reduced sensitivity to vincristine and doxorubicin.\",\n      \"method\": \"Co-immunoprecipitation, western blotting, siRNA knockdown, in vitro dephosphorylation assay, cytotoxicity assay\",\n      \"journal\": \"Cancer letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus functional dephosphorylation assay plus siRNA phenotype, single lab with multiple methods\",\n      \"pmids\": [\"24333728\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"G5PR overexpression in B1a cells suppressed BCR-mediated JNK signaling and drove differentiation of peritoneal B1a cells into IgM and IgG autoantibody-secreting plasmablasts in vitro. JNK inhibitor SP600125 recapitulated this effect in wild-type B1a cells, establishing that G5PR-mediated JNK suppression promotes B1a-to-plasmablast differentiation.\",\n      \"method\": \"G5PR-transgenic mouse B1a cell isolation, iGB culture system with IL-4/CD40L/BAFF, JNK inhibitor treatment, ELISA for autoantibody secretion, flow cytometry\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — transgenic gain-of-function combined with pharmacological validation, single lab\",\n      \"pmids\": [\"25601926\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Homozygous missense variants in PPP2R3C (p.L103P, p.L193S, p.F350S) cause 46,XY complete gonadal dysgenesis. Immunohistochemistry of dysgenetic gonads from patients showed decreased SOX9-phosphoprotein expression, implicating PPP2R3C in SOX9 phospho-signaling during testis development. Heterozygous males showed abnormal sperm morphology and impaired fertility.\",\n      \"method\": \"Exome/Sanger sequencing of patient cohort, immunohistochemistry for phospho-SOX9 in gonadal tissue\",\n      \"journal\": \"European journal of endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — human genetic variants with IHC molecular readout (phospho-SOX9), replicated across multiple families but no in vitro reconstitution\",\n      \"pmids\": [\"30893644\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Homozygous PPP2R3C p.L193S variant causes broad-spectrum gonadal dysgenesis in both 46,XY and 46,XX individuals. CRISPR/Cas9-generated homozygous Ppp2r3c knockout mice died during early embryogenesis (at or before 7.5 dpc), demonstrating that Ppp2r3c is essential for embryonic viability in mice.\",\n      \"method\": \"Sanger sequencing of patients, CRISPR/Cas9 knockout mice with timed embryo inspections\",\n      \"journal\": \"European journal of endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR knockout with defined embryonic lethal phenotype, confirmed by timed embryo inspection across multiple time points\",\n      \"pmids\": [\"34714774\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PPP2R3C is a distal centriole protein that localizes to centrosomes and functionally partners with centriolar proteins CEP350 and FOP. PPP2R3C counteracts the kinase activity of MAP3K1 at centrosomes: MAP3K1 knockout suppresses growth defects caused by PPP2R3C inactivation, and the two have opposing effects on basal and microtubule stress-induced JNK signaling. A disease-associated PPP2R3C variant is defective in centriolar localization and FOP binding. Acute MAP3K1 overexpression caused rapid centriole disintegration, phenocopying PPP2R3C loss.\",\n      \"method\": \"Systems genetics (functional genomic analyses), immunofluorescence/microscopy for centriolar localization, genetic epistasis (MAP3K1 KO suppression), JNK signaling assays, co-localization/binding studies with FOP and CEP350, disease variant analysis\",\n      \"journal\": \"Current biology : CB\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods including localization, genetic epistasis, kinase-phosphatase opposing activity assays, and disease-variant binding defect, replicated between preprint and peer-reviewed publication\",\n      \"pmids\": [\"39317195\", \"38617270\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PPP2R3C (B″gamma subunit of PP2A) interacts with Gli proteins and acts as a positive regulator of Hedgehog signaling. PPP2R3C disruption reduced expression of Gli1/2 and Hh target genes upon pathway activation and reduced growth of a Hh-dependent medulloblastoma cell line. An antagonistic relationship was established between PPP2R3C and MEKK1 kinase in regulating Gli protein phosphorylation.\",\n      \"method\": \"Co-immunoprecipitation (PPP2R3C-Gli interaction), siRNA/CRISPR knockdown with Hh pathway reporter assays and target gene qPCR, cell proliferation assays, phosphorylation analysis of Gli\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus loss-of-function with multiple pathway readouts, single lab with orthogonal methods\",\n      \"pmids\": [\"39173855\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PPP2R3C (G5PR/G4-1) is a regulatory subunit that bridges PP2A and PP5 phosphatases to multiple signaling complexes: it localizes to distal centrioles where it counteracts MAP3K1 kinase activity to maintain centrosome integrity and suppress JNK signaling; in immune cells it recruits PP5 to phosphorylated IKKβ to dampen NF-κB activation, regulates BCR-mediated JNK-Caspase-3 apoptosis in B cells and thymocytes, and promotes B-cell survival by suppressing late-phase JNK and Bim activation; it also dephosphorylates P-glycoprotein via a PP5/PPP2R3C complex to downregulate ABCB1 function, interacts with Gli transcription factors to positively regulate Hedgehog signaling, and its loss-of-function causes embryonic lethality in mice and syndromic 46,XY/XX gonadal dysgenesis in humans through impaired SOX9 phospho-signaling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PPP2R3C (G5PR/G4-1) is a non-catalytic regulatory/adaptor subunit that bridges the serine/threonine phosphatases PP2A and PP5 to specific phosphorylated targets, thereby restraining stress and kinase signaling across immune, developmental, and centrosomal contexts [#0, #4]. It associates with the PP2A A/C subunits and with PP5 through a TPR-domain interaction, forming a complex with phosphatase activity in vitro [#0]. A recurring theme of its biology is suppression of JNK signaling: conditional deletion in B cells and thymocytes causes hyperactivation of JNK and downstream apoptotic effectors (Bim in B cells; Caspase-3 and FasL in thymocytes), driving activation-induced and developmental cell death, whereas its induction or overexpression dampens late-phase JNK to promote B-cell survival and differentiation [#1, #3, #5]. As an adaptor it recruits PP5 to substrate phosphosites — to the autophosphorylated serine-rich C-terminus of activated IKK\\u03b2 to down-regulate NF-\\u03baB [#4], and to phosphorylated P-glycoprotein (ABCB1) to reduce its expression and drug efflux activity [#6]. At the distal centriole it partners with CEP350 and FOP and counteracts the kinase MAP3K1 to maintain centrosome integrity and limit JNK signaling, with a disease variant defective in centriolar localization and FOP binding [#10]; it analogously antagonizes MEKK1 to control Gli phosphorylation and positively regulates Hedgehog target-gene expression [#11]. Homozygous missense variants in PPP2R3C cause syndromic 46,XY/XX gonadal dysgenesis with reduced phospho-SOX9 in dysgenetic gonads, and complete loss is embryonic lethal in mice [#8, #9].\",\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Established the founding biochemical identity of PPP2R3C as a phosphatase-associated subunit, answering what enzymatic machinery it engages.\",\n      \"evidence\": \"Yeast two-hybrid, reciprocal pull-downs, and in vitro phosphatase assays in transfectants showing TPR-mediated association with PP2A (A/C subunits) and PP5\",\n      \"pmids\": [\"12167160\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"G5PR alone neither stimulated nor inhibited PP2A/PP5 activity, leaving its regulatory mechanism on phosphatase activity undefined\", \"no physiological substrate identified at this stage\", \"cell-cycle-dependent localization not linked to a function\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Defined a physiological requirement for PPP2R3C in restraining JNK-driven apoptosis, showing the subunit has a discrete cellular survival function rather than a generic housekeeping role.\",\n      \"evidence\": \"B-cell conditional knockout (CD19-Cre) with proliferation/apoptosis assays and signaling western blots; plus transcriptional induction analysis and cDNA rescue in WEHI-231 cells\",\n      \"pmids\": [\"16129705\", \"16343422\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"did not establish which phosphatase (PP2A vs PP5) mediates JNK suppression\", \"direct dephosphorylation target in the JNK pathway not identified\", \"selectivity for JNK over Erk/NF-\\u03baB/Akt mechanistically unexplained\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Showed the JNK-restraining function operates in a cell-type-specific manner, controlling a JNK-Caspase-3 apoptotic pathway in thymocytes distinct from the Bim-dependent route in B cells.\",\n      \"evidence\": \"T-cell-specific conditional knockout with flow cytometry, apoptosis assays, and western blotting for JNK, Caspase-3, Bim, FasL\",\n      \"pmids\": [\"18022237\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"why Bim is engaged in B cells but not thymocytes is unresolved\", \"molecular substrate upstream of JNK not defined\", \"no biochemical reconstitution of the phosphatase-JNK axis\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Resolved the molecular adaptor mechanism, demonstrating PPP2R3C bridges PP5 to a phosphorylated substrate to terminate signaling.\",\n      \"evidence\": \"Co-IP with domain-mapping mutagenesis of IKK\\u03b2 phospho-serines, siRNA knockdown of G4-1 and PP5, and NF-\\u03baB reporter assays under TNF\\u03b1\",\n      \"pmids\": [\"20925653\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"structural basis of phospho-IKK\\u03b2 recognition not determined\", \"whether the same adaptor logic explains JNK regulation untested\", \"in vivo relevance of the NF-\\u03baB axis not addressed\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Demonstrated gain-of-function consequences in vivo, linking PPP2R3C-mediated JNK suppression to B-cell survival, impaired affinity maturation, and autoimmunity.\",\n      \"evidence\": \"Transgenic overexpression mouse with immunohistochemistry, flow cytometry, in vitro AICD and JNK assays, and antibody affinity measurement\",\n      \"pmids\": [\"22753944\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"mechanism connecting JNK suppression to autoantibody production not dissected\", \"phosphatase substrate(s) controlling late-phase JNK unknown\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Extended the PP5-adaptor role beyond immune signaling, identifying P-glycoprotein as a substrate whose dephosphorylation modulates multidrug resistance.\",\n      \"evidence\": \"Co-IP, in vitro dephosphorylation of PKA/PKC-phosphorylated P-gp, siRNA knockdown with vincristine/doxorubicin cytotoxicity assays\",\n      \"pmids\": [\"24333728\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"specific phospho-residues on P-gp dephosphorylated not mapped\", \"single lab without reciprocal in vivo validation\", \"PP2A excluded but PP5 contribution not quantitatively separated from PPP2R3C\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Causally linked PPP2R3C-driven JNK suppression to B1a-cell-to-plasmablast differentiation using pharmacological phenocopy.\",\n      \"evidence\": \"Transgenic B1a-cell culture with JNK inhibitor SP600125 recapitulation, ELISA for autoantibody, flow cytometry\",\n      \"pmids\": [\"25601926\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"direct phosphatase substrate in B1a JNK pathway unidentified\", \"single-lab gain-of-function system\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Established a human Mendelian disease link, implicating PPP2R3C in SOX9 phospho-signaling during testis development.\",\n      \"evidence\": \"Exome/Sanger sequencing of a patient cohort with homozygous missense variants plus phospho-SOX9 immunohistochemistry of dysgenetic gonads\",\n      \"pmids\": [\"30893644\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"no in vitro reconstitution of variant effect on phosphatase function\", \"direct phosphatase-SOX9 biochemical relationship not demonstrated\", \"how each variant impairs the PP2A/PP5 complex unknown\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Broadened the disease spectrum to both 46,XY and 46,XX dysgenesis and proved PPP2R3C is essential for embryonic viability.\",\n      \"evidence\": \"Sanger sequencing of patients with the recurrent p.L193S variant and CRISPR/Cas9 knockout mice with timed embryo inspection\",\n      \"pmids\": [\"34714774\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"embryonic lethality precludes tissue-specific developmental mechanism\", \"molecular cause of early lethality (before 7.5 dpc) not defined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined a subcellular site and antagonist for PPP2R3C function, placing it at the distal centriole where it opposes MAP3K1 to preserve centrosome integrity, and identifying a parallel Gli/Hedgehog regulatory role.\",\n      \"evidence\": \"Functional genomics, centriolar immunofluorescence, genetic epistasis (MAP3K1 KO suppression), JNK assays, FOP/CEP350 binding, and disease-variant localization defect; plus Co-IP and Hh reporter/qPCR/proliferation assays for the Gli axis\",\n      \"pmids\": [\"39317195\", \"38617270\", \"39173855\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"whether PP2A or PP5 catalytic activity executes MAP3K1/Gli dephosphorylation at the centriole unresolved\", \"direct phospho-substrate dephosphorylated to counter MAP3K1 not identified\", \"link between centriolar function and gonadal/SOX9 phenotype not established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how PPP2R3C selects between its PP2A and PP5 catalytic partners for each substrate and how a single adaptor coordinates JNK, NF-\\u03baB, Hedgehog, centrosomal, and SOX9 outputs.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"no structural model of substrate-specific phosphatase targeting\", \"direct catalytic substrate for the developmental/SOX9 phenotype unidentified\", \"unifying biochemical logic across contexts undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 4, 6]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 4, 11]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [4, 6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [10]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [4, 6]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [4, 11]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [1, 3, 5]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [1, 3]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [8, 9]},\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [10]}\n    ],\n    \"complexes\": [\"PP2A holoenzyme (B''gamma regulatory subunit)\", \"PP5/PPP2R3C phosphatase complex\"],\n    \"partners\": [\"PPP2CA\", \"PPP5C\", \"IKBKB\", \"ABCB1\", \"MAP3K1\", \"FOP\", \"CEP350\", \"GLI\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}