{"gene":"CDCA2","run_date":"2026-06-09T22:57:18","timeline":{"discoveries":[{"year":2006,"finding":"Repo-Man (CDCA2) selectively recruits PP1γ onto mitotic chromatin at anaphase onset and into interphase. Mutating Repo-Man's PP1 binding domain abolishes PP1 recruitment to chromatin without disrupting Repo-Man's own chromatin binding. Knockdown of Repo-Man causes cell death by apoptosis.","method":"Stable isotope labeling proteomics, Co-IP, fluorescent protein time-lapse microscopy, RNA interference, site-directed mutagenesis","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, mutagenesis of PP1 binding domain, live-cell imaging, and RNAi phenotype, multiple orthogonal methods in a single study","pmids":["16492807"],"is_preprint":false},{"year":2006,"finding":"Repo-Man recruits PP1 to chromatin at anaphase onset, and preventing this recruitment can rescue anaphase chromosome segregation in condensin-depleted cells. Repo-Man-PP1 inactivates a chromosome-compacting activity ('RCA') that cooperates with condensin to preserve mitotic chromosome architecture.","method":"Conditional knockout of condensin subunit SMC2 in chicken DT40 cells, live-cell imaging, genetic epistasis (Repo-Man dominant-negative rescue)","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis in conditional knockout cells, live-cell imaging, multiple orthogonal approaches replicated across labs","pmids":["16998479"],"is_preprint":false},{"year":2010,"finding":"Repo-Man interacts with ATM and PP1 through distinct domains in Xenopus egg extracts. The Repo-Man:PP1 complex dephosphorylates and inactivates ATM, thereby suppressing ATM-dependent DNA damage checkpoint activation. Loss of PP1 binding abolishes this suppression; Repo-Man dissociates from active ATM at DNA damage sites.","method":"Xenopus egg extract biochemistry, Co-IP, domain mutagenesis (PP1 binding-deficient Repo-Man), overexpression/knockdown in human cells","journal":"Current biology : CB","confidence":"High","confidence_rationale":"Tier 2 / Strong — biochemical reconstitution in egg extracts, domain mutagenesis, reciprocal Co-IP, validated in human cells, multiple orthogonal methods","pmids":["20188555"],"is_preprint":false},{"year":2011,"finding":"PP1γ is the major histone H3 phosphatase for mitotically phosphorylated H3T3, H3S10, H3T11, and H3S28. Repo-Man, as the chromosome-bound PP1γ interactor, selectively promotes dephosphorylation of H3T3ph and H3T11ph: it directly targets H3T3ph for PP1γ-dependent dephosphorylation, while H3T11ph dephosphorylation is indirect. The PP1γ/Repo-Man complex opposes Haspin-mediated spreading of H3T3ph to chromosome arms and modulates chromosomal targeting of Aurora B and its substrate MCAK in a PP1-dependent manner.","method":"In vitro phosphatase assays, Co-IP, RNAi knockdown, immunofluorescence of Aurora B and MCAK localization, mutagenesis","journal":"Current biology : CB","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro phosphatase assay, substrate identification, mutagenesis, and functional epistasis with Aurora B pathway in a single study","pmids":["21514157"],"is_preprint":false},{"year":2011,"finding":"Repo-Man has two functionally separate domains during mitotic exit: a C-terminal domain targets it to bulk chromatin in early anaphase where it directs PP1 for dephosphorylation of H3T3, H3S10, and H3S28; an N-terminal domain localizes Repo-Man to the chromosome periphery later in anaphase where it recruits nuclear envelope components Importin β and Nup153 in a PP1-independent manner. Repo-Man:PP1 complex forms following dephosphorylation of Repo-Man in anaphase.","method":"Domain deletion/mutation analysis, live-cell imaging, immunofluorescence, Co-IP, fractionation","journal":"Developmental cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — domain separation experiments with multiple mutants, live-cell imaging, protein interaction studies, replicated with orthogonal methods","pmids":["21820363"],"is_preprint":false},{"year":2012,"finding":"Repo-Man and Sds22 are PP1-targeting subunits that counteract Aurora B-dependent phosphorylation of the outer kinetochore component Dsn1 during anaphase. Depletion of Repo-Man induced transient pauses during poleward chromosome movement and a high incidence of chromosome missegregation.","method":"RNAi screen using a phosphorylation biosensor, live-cell imaging, RNA interference-mediated depletion","journal":"The Journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — biosensor-based RNAi screen, live-cell imaging, single lab, two orthogonal methods","pmids":["22801782"],"is_preprint":false},{"year":2013,"finding":"Aurora B phosphorylates Repo-Man at S893, preventing its recruitment to chromosomes by histones. PP2A dephosphorylates S893, thereby promoting Repo-Man's targeting to chromosomes and PP1-mediated dephosphorylation of H3T3ph. Thus, Repo-Man-associated PP1 and PP2A collaborate to oppose chromosomal Aurora B targeting through a bistable feedback loop.","method":"Site-directed mutagenesis of S893, Co-IP, in vitro kinase assay, immunofluorescence, phospho-specific antibodies","journal":"Current biology : CB","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro kinase assay, phosphosite mutagenesis, reciprocal Co-IP, functional rescue experiments, multiple orthogonal methods","pmids":["23746640"],"is_preprint":false},{"year":2013,"finding":"Knockdown of CDCA2 in oral squamous cell carcinoma cells caused G1 phase cell-cycle arrest and upregulation of CDK inhibitors p21, p27, p15, and p16, and promoted apoptosis after cisplatin treatment, consistent with CDCA2 preventing ATM-dependent p53-p21 signaling.","method":"shRNA knockdown, flow cytometry, Western blot for cell cycle proteins","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — shRNA loss-of-function with defined cell-cycle phenotype, flow cytometry and Western blot, single lab","pmids":["23418564"],"is_preprint":false},{"year":2017,"finding":"Repo-Man/PP1 promotes accumulation of NuMA at the cortex during anaphase. In metaphase, p37/UBXN2B negatively regulates PP1/Repo-Man, limiting cortical NuMA levels and thereby controlling spindle orientation. This regulation is independent of Gαi, Aurora A, and PP2A.","method":"RNAi depletion, immunofluorescence, live-cell imaging, epistasis experiments with Gαi/Aurora A/PP2A inhibitors","journal":"The Journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNAi with defined spindle orientation phenotype, epistasis with multiple regulators, single lab","pmids":["29222185"],"is_preprint":false},{"year":2017,"finding":"Repo-Man/PP1 in interphase is enriched on condensed chromatin at the nuclear periphery via Nup153 and regulates heterochromatin formation by dephosphorylating H3S28, promoting HP1 binding and H3K27me3 recruitment. Repo-Man depletion alters peripheral localization of subtelomeric regions and alleviates repression of polycomb telomeric genes.","method":"Immunofluorescence, ChIP-seq (proteogenomic approach), RNAi depletion, live-cell imaging, fractionation","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP-seq combined with RNAi, immunofluorescence, and functional gene expression readouts; multiple orthogonal methods","pmids":["28091603"],"is_preprint":false},{"year":2020,"finding":"Aurora B regulates PP1γ-Repo-Man interactions on mitotic chromosomes: Aurora B phosphorylates Repo-Man, disrupting its interaction with PP1γ and causing PP1γ dissociation from chromosomes. Repo-Man mutants that cannot be phosphorylated, or Aurora B inhibition, cause retention of PP1γ on chromatin and prolong chromosome condensation.","method":"Co-immunoprecipitation, immunofluorescence microscopy, Aurora B inhibitor treatment, phosphorylation-resistant Repo-Man mutant overexpression","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, mutagenesis, kinase inhibitor, immunofluorescence; single lab, two orthogonal methods","pmids":["32938714"],"is_preprint":false},{"year":2022,"finding":"Repo-Man/PP1 mediates dephosphorylation of lamin A at serine 22 during mitotic exit. The interaction between Repo-Man and lamin A is mediated by SUMOylation of Repo-Man. Depletion of Repo-Man causes nuclear envelope defects and hyperphosphorylation of lamin A S22; this can be rescued by wild-type but not SUMOylation-deficient Repo-Man.","method":"Co-IP (in vivo and in vitro), SUMOylation-deficient mutant rescue, Western blot for lamin A S22ph, immunofluorescence for NE defects, RNAi depletion","journal":"Open biology","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro and in vivo interaction, site-specific mutagenesis rescue, phospho-specific readout, multiple orthogonal methods","pmids":["35414260"],"is_preprint":false},{"year":2023,"finding":"CDCA2 inhibits ubiquitin-dependent Aurora kinase A (AURKA) protein degradation by acting on SMURF1 (SMAD specific E3 ubiquitin protein ligase 1), thereby stabilizing AURKA protein and promoting melanoma cell proliferation and migration. AURKA knockdown inhibits CDCA2 overexpression-induced proliferation.","method":"Co-immunoprecipitation, ubiquitination analysis, protein stability experiments, GeneChip/IPA bioinformatics, in vitro and in vivo tumor models","journal":"European journal of cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, ubiquitination assay, protein stability assay, epistasis; single lab with multiple orthogonal methods","pmids":["37196484"],"is_preprint":false},{"year":2026,"finding":"CDCA2 (Repo-Man) is required for stabilization of cMYC and MYCN proteins in cancer cells. Proximity ligation assays demonstrate that both cMYC and MYCN are in close proximity to CDCA2 in vivo. CDCA2 is itself a direct MYC target gene (validated by ChIP and promoter mutation), establishing a positive feedback loop. CDCA2 depletion reduces viability of triple-negative breast cancer, neuroblastoma, and colon cancer cells.","method":"RNA interference, degron-mediated degradation of CDCA2, proximity ligation assay, chromatin immunoprecipitation, promoter mutation studies","journal":"Open biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — proximity ligation, ChIP, promoter mutagenesis, and functional depletion; single lab, multiple orthogonal methods","pmids":["41844234"],"is_preprint":false},{"year":2025,"finding":"PHD1-mediated prolyl hydroxylation of Repo-Man (CDCA2) at P604 is required for proper mitotic progression. Hydroxylation at P604 is required for the interaction of Repo-Man with PP2A-B56γ; the P604A mutant shows reduced PP2A interaction. Loss of PHD1 or expression of Repo-Man P604A increases H3T3 phosphorylation in prometaphase, delays mitotic completion, causes chromosome alignment/segregation defects, and increases cell death.","method":"Mass spectrometry (proline hydroxylation identification), siRNA depletion, point mutant (P604A) expression rescue, Co-IP for PP2A-B56γ, immunofluorescence and live-cell imaging, H3T3 phosphorylation assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1-2 / Moderate — mass spectrometry PTM identification, site-directed mutagenesis rescue, protein interaction studies, live-cell imaging; preprint, single lab, multiple orthogonal methods","pmids":["bio_10.1101_2025.05.06.652400"],"is_preprint":true}],"current_model":"CDCA2 (Repo-Man) is a PP1γ-targeting subunit that recruits PP1γ to chromatin at anaphase onset via a dedicated C-terminal chromatin-binding domain and a separable PP1-binding domain; the PP1/Repo-Man complex dephosphorylates histone H3 at T3, S10, S28 and T11 to regulate chromosome architecture, Aurora B centromeric targeting, and nuclear envelope reassembly during mitotic exit, while in interphase it promotes heterochromatin formation, dephosphorylates lamin A S22, and suppresses ATM-dependent DNA damage signaling; Aurora B phosphorylates Repo-Man at S893 to oppose its chromosomal recruitment (counteracted by PP2A), PHD1 hydroxylates Repo-Man at P604 to facilitate PP2A-B56γ interaction and proper mitotic progression, and in cancer cells CDCA2 stabilizes MYC/MYCN proteins and is itself a MYC transcriptional target, forming an oncogenic positive feedback loop."},"narrative":{"mechanistic_narrative":"CDCA2 (Repo-Man) is a chromatin-targeting regulatory subunit that recruits protein phosphatase PP1γ onto mitotic chromatin at anaphase onset and into interphase, coordinating chromosome architecture, mitotic exit, and nuclear reassembly [PMID:16492807, PMID:21820363]. It uses functionally separable domains: a C-terminal domain that targets bulk chromatin and directs PP1-dependent dephosphorylation of mitotic histone H3 marks (H3T3ph, H3S10ph, H3S28ph), and an N-terminal domain that recruits nuclear envelope components Importin β and Nup153 in a PP1-independent manner [PMID:21514157, PMID:21820363]. As the chromosome-bound PP1γ interactor, the complex selectively reverses Haspin-driven H3T3ph and thereby modulates centromeric targeting of Aurora B and its substrate MCAK, while opposing a condensin-cooperating chromosome-compacting activity to preserve mitotic chromosome structure [PMID:16998479, PMID:21514157]. Its chromosomal recruitment is set by a phospho-switch in which Aurora B phosphorylates Repo-Man at S893 to block histone-mediated targeting and dissociate PP1γ, opposed by PP2A-mediated dephosphorylation, forming a bistable feedback loop that delimits Aurora B activity [PMID:23746640, PMID:32938714]. Beyond histones, the PP1/Repo-Man complex dephosphorylates and inactivates ATM to suppress DNA-damage checkpoint signaling [PMID:20188555], dephosphorylates lamin A at S22 during mitotic exit through a SUMOylation-dependent interaction required for proper nuclear envelope reformation [PMID:35414260], and in interphase promotes peripheral heterochromatin formation by dephosphorylating H3S28 to enable HP1 binding and H3K27me3 recruitment [PMID:28091603]. In cancer cells CDCA2 acts as an oncogenic stabilizer of MYC/MYCN proteins and is itself a direct MYC target gene, establishing a positive feedback loop whose disruption reduces viability of multiple tumor types [PMID:41844234].","teleology":[{"year":2006,"claim":"Established CDCA2 as a dedicated PP1γ-targeting subunit that delivers the phosphatase specifically to chromatin, defining how a generic phosphatase achieves spatial specificity in mitosis.","evidence":"Proteomics, reciprocal Co-IP, PP1-binding domain mutagenesis, and live-cell imaging in human cells","pmids":["16492807"],"confidence":"High","gaps":["Histone and non-histone substrates not yet identified","Mechanism of chromatin targeting not yet mapped to a domain"]},{"year":2006,"claim":"Showed that Repo-Man/PP1 inactivates a chromosome-compacting activity cooperating with condensin, placing the complex within mitotic chromosome architecture control.","evidence":"Conditional SMC2 knockout in chicken DT40 cells with dominant-negative epistasis and live-cell imaging","pmids":["16998479"],"confidence":"High","gaps":["Molecular identity of the 'RCA' activity unresolved","Direct phosphatase substrates underlying compaction control not defined"]},{"year":2010,"claim":"Extended Repo-Man function beyond chromosome architecture by showing the complex dephosphorylates and inactivates ATM to restrain DNA-damage checkpoint signaling.","evidence":"Xenopus egg extract biochemistry, domain mutagenesis, reciprocal Co-IP, validated in human cells","pmids":["20188555"],"confidence":"High","gaps":["ATM dephosphorylation sites not pinpointed","Physiological context where this suppression dominates not defined"]},{"year":2011,"claim":"Identified the histone H3 substrates of the complex and connected H3T3ph reversal to Aurora B centromeric targeting, linking phosphatase activity to kinase positioning.","evidence":"In vitro phosphatase assays, RNAi, mutagenesis, and Aurora B/MCAK localization imaging","pmids":["21514157"],"confidence":"High","gaps":["Direct versus indirect dephosphorylation of H3S10/H3T11 not fully separated","Quantitative contribution to Aurora B gradient unresolved"]},{"year":2011,"claim":"Resolved the protein into two separable functional modules — a chromatin-targeting/H3-dephosphorylating C-terminus and a PP1-independent nuclear envelope-recruiting N-terminus — explaining its dual roles at mitotic exit.","evidence":"Domain deletion/mutation, live-cell imaging, Co-IP, and fractionation","pmids":["21820363"],"confidence":"High","gaps":["How the two domains are temporally coordinated within anaphase unclear","Structural basis of Importin β/Nup153 recruitment not defined"]},{"year":2012,"claim":"Showed Repo-Man (with Sds22) counteracts Aurora B phosphorylation of the kinetochore component Dsn1, tying its activity to faithful chromosome segregation.","evidence":"Phosphorylation-biosensor RNAi screen and live-cell imaging","pmids":["22801782"],"confidence":"Medium","gaps":["Direct dephosphorylation of Dsn1 not biochemically demonstrated","Relative contributions of Repo-Man and Sds22 not separated"]},{"year":2013,"claim":"Defined the phospho-switch governing Repo-Man recruitment: Aurora B phosphorylation at S893 blocks chromatin targeting and PP2A reverses it, establishing a bistable kinase/phosphatase feedback loop.","evidence":"S893 mutagenesis, in vitro kinase assay, reciprocal Co-IP, and functional rescue","pmids":["23746640"],"confidence":"High","gaps":["Quantitative thresholds of the bistable switch not modeled","Whether other Aurora B sites contribute not excluded"]},{"year":2013,"claim":"Provided cancer-relevant loss-of-function evidence that CDCA2 prevents ATM-dependent p53-p21 signaling and supports proliferation, connecting its checkpoint-suppressing role to tumor cell survival.","evidence":"shRNA knockdown with cell-cycle flow cytometry and CDK-inhibitor Western blots in oral squamous carcinoma cells","pmids":["23418564"],"confidence":"Medium","gaps":["Direct link between CDCA2 phosphatase activity and p21/p27 induction not biochemically shown","Single cancer cell context"]},{"year":2017,"claim":"Demonstrated an interphase chromatin role: Repo-Man/PP1 dephosphorylates H3S28 at the nuclear periphery to promote HP1 binding, H3K27me3 recruitment, and heterochromatin organization.","evidence":"ChIP-seq, RNAi, immunofluorescence, and gene-expression readouts","pmids":["28091603"],"confidence":"High","gaps":["Mechanism coupling Nup153 anchoring to substrate selection unclear","Causality between H3S28 dephosphorylation and H3K27me3 deposition not fully dissected"]},{"year":2017,"claim":"Linked Repo-Man/PP1 to spindle orientation through cortical NuMA accumulation, with p37/UBXN2B as a negative regulator, broadening its mitotic remit beyond chromatin.","evidence":"RNAi, immunofluorescence, live-cell imaging, and epistasis with Gαi/Aurora A/PP2A inhibitors","pmids":["29222185"],"confidence":"Medium","gaps":["Direct phosphatase substrate at the cortex not identified","Mechanism by which p37 inhibits the complex undefined"]},{"year":2020,"claim":"Reinforced that Aurora B phosphorylation disrupts the PP1γ-Repo-Man interaction itself, controlling chromosome condensation dynamics through PP1γ retention.","evidence":"Co-IP, phospho-resistant mutant overexpression, Aurora B inhibition, and immunofluorescence","pmids":["32938714"],"confidence":"Medium","gaps":["Single-lab confirmation of S893-specific effect on PP1γ binding","Structural basis of phospho-disrupted PP1 binding unknown"]},{"year":2022,"claim":"Identified lamin A S22 as a mitotic-exit substrate and SUMOylation of Repo-Man as the targeting mechanism, mechanistically connecting the complex to nuclear envelope reformation.","evidence":"In vitro/in vivo Co-IP, SUMOylation-deficient mutant rescue, phospho-specific Western blots, and NE-defect imaging","pmids":["35414260"],"confidence":"High","gaps":["SUMO sites on Repo-Man not mapped","Whether SUMOylation regulates other substrate interactions unknown"]},{"year":2023,"claim":"Revealed a tumor-promoting mechanism in which CDCA2 stabilizes AURKA by acting on the E3 ligase SMURF1 to block its ubiquitin-dependent degradation, driving melanoma proliferation.","evidence":"Co-IP, ubiquitination and protein stability assays, epistasis, and in vitro/in vivo tumor models","pmids":["37196484"],"confidence":"Medium","gaps":["Whether PP1 phosphatase activity is required for AURKA stabilization unclear","Direct CDCA2-SMURF1 biochemical mechanism incompletely defined"]},{"year":2026,"claim":"Established CDCA2 as both a stabilizer of MYC/MYCN proteins and a direct MYC target gene, defining an oncogenic positive feedback loop whose disruption reduces tumor cell viability.","evidence":"RNAi, degron degradation, proximity ligation, ChIP, and promoter mutation studies across multiple cancer cell types","pmids":["41844234"],"confidence":"Medium","gaps":["Mechanism by which CDCA2 stabilizes MYC/MYCN not biochemically resolved","Whether stabilization depends on PP1 or phosphatase activity unknown"]},{"year":2025,"claim":"Showed PHD1-mediated prolyl hydroxylation of Repo-Man at P604 is required for PP2A-B56γ interaction and proper mitotic progression, adding a PTM-controlled layer to phosphatase complex assembly.","evidence":"Mass spectrometry PTM identification, P604A mutant rescue, Co-IP for PP2A-B56γ, and live-cell imaging (preprint)","pmids":["bio_10.1101_2025.05.06.652400"],"confidence":"Medium","gaps":["Preprint, single lab not yet peer-reviewed","How oxygen-sensitive hydroxylation integrates with the Aurora B/PP2A switch unclear"]},{"year":null,"claim":"How CDCA2's well-defined mitotic phosphatase-targeting activity mechanistically connects to its oncogenic MYC/MYCN and AURKA stabilization functions — and whether these depend on PP1 catalytic activity — remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of the chromatin-bound PP1γ/Repo-Man complex","Biochemical mechanism of MYC/MYCN and AURKA protein stabilization undefined","Whether oncogenic roles require phosphatase activity untested"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,4,6]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,4]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3,2,11]},{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[3,9]}],"localization":[{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[0,3,4]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[9]},{"term_id":"GO:0005635","term_label":"nuclear envelope","supporting_discovery_ids":[4,11]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,9]}],"pathway":[{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[0,1,3,4,6]},{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[3,9]},{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[2]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[12,13]}],"complexes":["PP1γ/Repo-Man complex"],"partners":["PPP1CC","ATM","NUP153","KPNB1","AURKB","LMNA","MYC","MYCN"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q69YH5","full_name":"Cell division cycle-associated protein 2","aliases":["Recruits PP1 onto mitotic chromatin at anaphase protein","Repo-Man"],"length_aa":1023,"mass_kda":112.7,"function":"Regulator of chromosome structure during mitosis required for condensin-depleted chromosomes to retain their compact architecture through anaphase. Acts by mediating the recruitment of phosphatase PP1-gamma subunit (PPP1CC) to chromatin at anaphase and into the following interphase. At anaphase onset, its association with chromatin targets a pool of PPP1CC to dephosphorylate substrates","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q69YH5/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CDCA2","classification":"Not Classified","n_dependent_lines":13,"n_total_lines":1208,"dependency_fraction":0.01076158940397351},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"KPNB1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/CDCA2","total_profiled":1310},"omim":[{"mim_id":"618785","title":"CELL DIVISION CYCLE-ASSOCIATED PROTEIN 2; CDCA2","url":"https://www.omim.org/entry/618785"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Group enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"bone marrow","ntpm":6.1},{"tissue":"lymphoid tissue","ntpm":10.6},{"tissue":"testis","ntpm":18.2}],"url":"https://www.proteinatlas.org/search/CDCA2"},"hgnc":{"alias_symbol":["Repo-Man","PPP1R81"],"prev_symbol":[]},"alphafold":{"accession":"Q69YH5","domains":[],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q69YH5","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q69YH5-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q69YH5-F1-predicted_aligned_error_v6.png","plddt_mean":46.22},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CDCA2","jax_strain_url":"https://www.jax.org/strain/search?query=CDCA2"},"sequence":{"accession":"Q69YH5","fasta_url":"https://rest.uniprot.org/uniprotkb/Q69YH5.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q69YH5/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q69YH5"}},"corpus_meta":[{"pmid":"16492807","id":"PMC_16492807","title":"Repo-Man recruits PP1 gamma to chromatin and is essential for cell viability.","date":"2006","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16492807","citation_count":216,"is_preprint":false},{"pmid":"16998479","id":"PMC_16998479","title":"Condensin and Repo-Man-PP1 co-operate in the regulation of chromosome architecture during mitosis.","date":"2006","source":"Nature cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16998479","citation_count":180,"is_preprint":false},{"pmid":"21514157","id":"PMC_21514157","title":"PP1/Repo-man dephosphorylates mitotic histone H3 at T3 and regulates chromosomal aurora B targeting.","date":"2011","source":"Current biology : CB","url":"https://pubmed.ncbi.nlm.nih.gov/21514157","citation_count":167,"is_preprint":false},{"pmid":"21820363","id":"PMC_21820363","title":"Repo-Man coordinates chromosomal reorganization with nuclear envelope reassembly during mitotic exit.","date":"2011","source":"Developmental 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biology","url":"https://pubmed.ncbi.nlm.nih.gov/22801782","citation_count":72,"is_preprint":false},{"pmid":"23418564","id":"PMC_23418564","title":"Overexpression of CDCA2 in human squamous cell carcinoma: correlation with prevention of G1 phase arrest and apoptosis.","date":"2013","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/23418564","citation_count":61,"is_preprint":false},{"pmid":"31196027","id":"PMC_31196027","title":"CDCA2 promotes the proliferation of colorectal cancer cells by activating the AKT/CCND1 pathway in vitro and in vivo.","date":"2019","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/31196027","citation_count":48,"is_preprint":false},{"pmid":"28091603","id":"PMC_28091603","title":"Repo-Man/PP1 regulates heterochromatin formation in interphase.","date":"2017","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/28091603","citation_count":43,"is_preprint":false},{"pmid":"32509575","id":"PMC_32509575","title":"CDCA2 Inhibits Apoptosis and Promotes Cell Proliferation in Prostate Cancer and Is Directly Regulated by HIF-1α Pathway.","date":"2020","source":"Frontiers in oncology","url":"https://pubmed.ncbi.nlm.nih.gov/32509575","citation_count":34,"is_preprint":false},{"pmid":"34103686","id":"PMC_34103686","title":"CDCA2 protects against oxidative stress by promoting BRCA1-NRF2 signaling in hepatocellular carcinoma.","date":"2021","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/34103686","citation_count":31,"is_preprint":false},{"pmid":"24563358","id":"PMC_24563358","title":"Repo-man at the intersection of chromatin remodelling, DNA repair, nuclear envelope organization, and cancer progression.","date":"2014","source":"Advances in experimental medicine and biology","url":"https://pubmed.ncbi.nlm.nih.gov/24563358","citation_count":29,"is_preprint":false},{"pmid":"22555598","id":"PMC_22555598","title":"Repo-Man-PP1: a link between chromatin remodelling and nuclear envelope 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\"finding\": \"Repo-Man (CDCA2) selectively recruits PP1γ onto mitotic chromatin at anaphase onset and into interphase. Mutating Repo-Man's PP1 binding domain abolishes PP1 recruitment to chromatin without disrupting Repo-Man's own chromatin binding. Knockdown of Repo-Man causes cell death by apoptosis.\",\n      \"method\": \"Stable isotope labeling proteomics, Co-IP, fluorescent protein time-lapse microscopy, RNA interference, site-directed mutagenesis\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, mutagenesis of PP1 binding domain, live-cell imaging, and RNAi phenotype, multiple orthogonal methods in a single study\",\n      \"pmids\": [\"16492807\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Repo-Man recruits PP1 to chromatin at anaphase onset, and preventing this recruitment can rescue anaphase chromosome segregation in condensin-depleted cells. Repo-Man-PP1 inactivates a chromosome-compacting activity ('RCA') that cooperates with condensin to preserve mitotic chromosome architecture.\",\n      \"method\": \"Conditional knockout of condensin subunit SMC2 in chicken DT40 cells, live-cell imaging, genetic epistasis (Repo-Man dominant-negative rescue)\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis in conditional knockout cells, live-cell imaging, multiple orthogonal approaches replicated across labs\",\n      \"pmids\": [\"16998479\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Repo-Man interacts with ATM and PP1 through distinct domains in Xenopus egg extracts. The Repo-Man:PP1 complex dephosphorylates and inactivates ATM, thereby suppressing ATM-dependent DNA damage checkpoint activation. Loss of PP1 binding abolishes this suppression; Repo-Man dissociates from active ATM at DNA damage sites.\",\n      \"method\": \"Xenopus egg extract biochemistry, Co-IP, domain mutagenesis (PP1 binding-deficient Repo-Man), overexpression/knockdown in human cells\",\n      \"journal\": \"Current biology : CB\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — biochemical reconstitution in egg extracts, domain mutagenesis, reciprocal Co-IP, validated in human cells, multiple orthogonal methods\",\n      \"pmids\": [\"20188555\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"PP1γ is the major histone H3 phosphatase for mitotically phosphorylated H3T3, H3S10, H3T11, and H3S28. Repo-Man, as the chromosome-bound PP1γ interactor, selectively promotes dephosphorylation of H3T3ph and H3T11ph: it directly targets H3T3ph for PP1γ-dependent dephosphorylation, while H3T11ph dephosphorylation is indirect. The PP1γ/Repo-Man complex opposes Haspin-mediated spreading of H3T3ph to chromosome arms and modulates chromosomal targeting of Aurora B and its substrate MCAK in a PP1-dependent manner.\",\n      \"method\": \"In vitro phosphatase assays, Co-IP, RNAi knockdown, immunofluorescence of Aurora B and MCAK localization, mutagenesis\",\n      \"journal\": \"Current biology : CB\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro phosphatase assay, substrate identification, mutagenesis, and functional epistasis with Aurora B pathway in a single study\",\n      \"pmids\": [\"21514157\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Repo-Man has two functionally separate domains during mitotic exit: a C-terminal domain targets it to bulk chromatin in early anaphase where it directs PP1 for dephosphorylation of H3T3, H3S10, and H3S28; an N-terminal domain localizes Repo-Man to the chromosome periphery later in anaphase where it recruits nuclear envelope components Importin β and Nup153 in a PP1-independent manner. Repo-Man:PP1 complex forms following dephosphorylation of Repo-Man in anaphase.\",\n      \"method\": \"Domain deletion/mutation analysis, live-cell imaging, immunofluorescence, Co-IP, fractionation\",\n      \"journal\": \"Developmental cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — domain separation experiments with multiple mutants, live-cell imaging, protein interaction studies, replicated with orthogonal methods\",\n      \"pmids\": [\"21820363\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Repo-Man and Sds22 are PP1-targeting subunits that counteract Aurora B-dependent phosphorylation of the outer kinetochore component Dsn1 during anaphase. Depletion of Repo-Man induced transient pauses during poleward chromosome movement and a high incidence of chromosome missegregation.\",\n      \"method\": \"RNAi screen using a phosphorylation biosensor, live-cell imaging, RNA interference-mediated depletion\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — biosensor-based RNAi screen, live-cell imaging, single lab, two orthogonal methods\",\n      \"pmids\": [\"22801782\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Aurora B phosphorylates Repo-Man at S893, preventing its recruitment to chromosomes by histones. PP2A dephosphorylates S893, thereby promoting Repo-Man's targeting to chromosomes and PP1-mediated dephosphorylation of H3T3ph. Thus, Repo-Man-associated PP1 and PP2A collaborate to oppose chromosomal Aurora B targeting through a bistable feedback loop.\",\n      \"method\": \"Site-directed mutagenesis of S893, Co-IP, in vitro kinase assay, immunofluorescence, phospho-specific antibodies\",\n      \"journal\": \"Current biology : CB\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro kinase assay, phosphosite mutagenesis, reciprocal Co-IP, functional rescue experiments, multiple orthogonal methods\",\n      \"pmids\": [\"23746640\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Knockdown of CDCA2 in oral squamous cell carcinoma cells caused G1 phase cell-cycle arrest and upregulation of CDK inhibitors p21, p27, p15, and p16, and promoted apoptosis after cisplatin treatment, consistent with CDCA2 preventing ATM-dependent p53-p21 signaling.\",\n      \"method\": \"shRNA knockdown, flow cytometry, Western blot for cell cycle proteins\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — shRNA loss-of-function with defined cell-cycle phenotype, flow cytometry and Western blot, single lab\",\n      \"pmids\": [\"23418564\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Repo-Man/PP1 promotes accumulation of NuMA at the cortex during anaphase. In metaphase, p37/UBXN2B negatively regulates PP1/Repo-Man, limiting cortical NuMA levels and thereby controlling spindle orientation. This regulation is independent of Gαi, Aurora A, and PP2A.\",\n      \"method\": \"RNAi depletion, immunofluorescence, live-cell imaging, epistasis experiments with Gαi/Aurora A/PP2A inhibitors\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNAi with defined spindle orientation phenotype, epistasis with multiple regulators, single lab\",\n      \"pmids\": [\"29222185\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Repo-Man/PP1 in interphase is enriched on condensed chromatin at the nuclear periphery via Nup153 and regulates heterochromatin formation by dephosphorylating H3S28, promoting HP1 binding and H3K27me3 recruitment. Repo-Man depletion alters peripheral localization of subtelomeric regions and alleviates repression of polycomb telomeric genes.\",\n      \"method\": \"Immunofluorescence, ChIP-seq (proteogenomic approach), RNAi depletion, live-cell imaging, fractionation\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP-seq combined with RNAi, immunofluorescence, and functional gene expression readouts; multiple orthogonal methods\",\n      \"pmids\": [\"28091603\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Aurora B regulates PP1γ-Repo-Man interactions on mitotic chromosomes: Aurora B phosphorylates Repo-Man, disrupting its interaction with PP1γ and causing PP1γ dissociation from chromosomes. Repo-Man mutants that cannot be phosphorylated, or Aurora B inhibition, cause retention of PP1γ on chromatin and prolong chromosome condensation.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence microscopy, Aurora B inhibitor treatment, phosphorylation-resistant Repo-Man mutant overexpression\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, mutagenesis, kinase inhibitor, immunofluorescence; single lab, two orthogonal methods\",\n      \"pmids\": [\"32938714\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Repo-Man/PP1 mediates dephosphorylation of lamin A at serine 22 during mitotic exit. The interaction between Repo-Man and lamin A is mediated by SUMOylation of Repo-Man. Depletion of Repo-Man causes nuclear envelope defects and hyperphosphorylation of lamin A S22; this can be rescued by wild-type but not SUMOylation-deficient Repo-Man.\",\n      \"method\": \"Co-IP (in vivo and in vitro), SUMOylation-deficient mutant rescue, Western blot for lamin A S22ph, immunofluorescence for NE defects, RNAi depletion\",\n      \"journal\": \"Open biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro and in vivo interaction, site-specific mutagenesis rescue, phospho-specific readout, multiple orthogonal methods\",\n      \"pmids\": [\"35414260\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CDCA2 inhibits ubiquitin-dependent Aurora kinase A (AURKA) protein degradation by acting on SMURF1 (SMAD specific E3 ubiquitin protein ligase 1), thereby stabilizing AURKA protein and promoting melanoma cell proliferation and migration. AURKA knockdown inhibits CDCA2 overexpression-induced proliferation.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination analysis, protein stability experiments, GeneChip/IPA bioinformatics, in vitro and in vivo tumor models\",\n      \"journal\": \"European journal of cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, ubiquitination assay, protein stability assay, epistasis; single lab with multiple orthogonal methods\",\n      \"pmids\": [\"37196484\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"CDCA2 (Repo-Man) is required for stabilization of cMYC and MYCN proteins in cancer cells. Proximity ligation assays demonstrate that both cMYC and MYCN are in close proximity to CDCA2 in vivo. CDCA2 is itself a direct MYC target gene (validated by ChIP and promoter mutation), establishing a positive feedback loop. CDCA2 depletion reduces viability of triple-negative breast cancer, neuroblastoma, and colon cancer cells.\",\n      \"method\": \"RNA interference, degron-mediated degradation of CDCA2, proximity ligation assay, chromatin immunoprecipitation, promoter mutation studies\",\n      \"journal\": \"Open biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — proximity ligation, ChIP, promoter mutagenesis, and functional depletion; single lab, multiple orthogonal methods\",\n      \"pmids\": [\"41844234\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PHD1-mediated prolyl hydroxylation of Repo-Man (CDCA2) at P604 is required for proper mitotic progression. Hydroxylation at P604 is required for the interaction of Repo-Man with PP2A-B56γ; the P604A mutant shows reduced PP2A interaction. Loss of PHD1 or expression of Repo-Man P604A increases H3T3 phosphorylation in prometaphase, delays mitotic completion, causes chromosome alignment/segregation defects, and increases cell death.\",\n      \"method\": \"Mass spectrometry (proline hydroxylation identification), siRNA depletion, point mutant (P604A) expression rescue, Co-IP for PP2A-B56γ, immunofluorescence and live-cell imaging, H3T3 phosphorylation assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — mass spectrometry PTM identification, site-directed mutagenesis rescue, protein interaction studies, live-cell imaging; preprint, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"bio_10.1101_2025.05.06.652400\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"CDCA2 (Repo-Man) is a PP1γ-targeting subunit that recruits PP1γ to chromatin at anaphase onset via a dedicated C-terminal chromatin-binding domain and a separable PP1-binding domain; the PP1/Repo-Man complex dephosphorylates histone H3 at T3, S10, S28 and T11 to regulate chromosome architecture, Aurora B centromeric targeting, and nuclear envelope reassembly during mitotic exit, while in interphase it promotes heterochromatin formation, dephosphorylates lamin A S22, and suppresses ATM-dependent DNA damage signaling; Aurora B phosphorylates Repo-Man at S893 to oppose its chromosomal recruitment (counteracted by PP2A), PHD1 hydroxylates Repo-Man at P604 to facilitate PP2A-B56γ interaction and proper mitotic progression, and in cancer cells CDCA2 stabilizes MYC/MYCN proteins and is itself a MYC transcriptional target, forming an oncogenic positive feedback loop.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CDCA2 (Repo-Man) is a chromatin-targeting regulatory subunit that recruits protein phosphatase PP1\\u03b3 onto mitotic chromatin at anaphase onset and into interphase, coordinating chromosome architecture, mitotic exit, and nuclear reassembly [#0, #4]. It uses functionally separable domains: a C-terminal domain that targets bulk chromatin and directs PP1-dependent dephosphorylation of mitotic histone H3 marks (H3T3ph, H3S10ph, H3S28ph), and an N-terminal domain that recruits nuclear envelope components Importin \\u03b2 and Nup153 in a PP1-independent manner [#3, #4]. As the chromosome-bound PP1\\u03b3 interactor, the complex selectively reverses Haspin-driven H3T3ph and thereby modulates centromeric targeting of Aurora B and its substrate MCAK, while opposing a condensin-cooperating chromosome-compacting activity to preserve mitotic chromosome structure [#1, #3]. Its chromosomal recruitment is set by a phospho-switch in which Aurora B phosphorylates Repo-Man at S893 to block histone-mediated targeting and dissociate PP1\\u03b3, opposed by PP2A-mediated dephosphorylation, forming a bistable feedback loop that delimits Aurora B activity [#6, #10]. Beyond histones, the PP1/Repo-Man complex dephosphorylates and inactivates ATM to suppress DNA-damage checkpoint signaling [#2], dephosphorylates lamin A at S22 during mitotic exit through a SUMOylation-dependent interaction required for proper nuclear envelope reformation [#11], and in interphase promotes peripheral heterochromatin formation by dephosphorylating H3S28 to enable HP1 binding and H3K27me3 recruitment [#9]. In cancer cells CDCA2 acts as an oncogenic stabilizer of MYC/MYCN proteins and is itself a direct MYC target gene, establishing a positive feedback loop whose disruption reduces viability of multiple tumor types [#13].\",\n  \"teleology\": [\n    {\n      \"year\": 2006,\n      \"claim\": \"Established CDCA2 as a dedicated PP1\\u03b3-targeting subunit that delivers the phosphatase specifically to chromatin, defining how a generic phosphatase achieves spatial specificity in mitosis.\",\n      \"evidence\": \"Proteomics, reciprocal Co-IP, PP1-binding domain mutagenesis, and live-cell imaging in human cells\",\n      \"pmids\": [\"16492807\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Histone and non-histone substrates not yet identified\", \"Mechanism of chromatin targeting not yet mapped to a domain\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Showed that Repo-Man/PP1 inactivates a chromosome-compacting activity cooperating with condensin, placing the complex within mitotic chromosome architecture control.\",\n      \"evidence\": \"Conditional SMC2 knockout in chicken DT40 cells with dominant-negative epistasis and live-cell imaging\",\n      \"pmids\": [\"16998479\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular identity of the 'RCA' activity unresolved\", \"Direct phosphatase substrates underlying compaction control not defined\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Extended Repo-Man function beyond chromosome architecture by showing the complex dephosphorylates and inactivates ATM to restrain DNA-damage checkpoint signaling.\",\n      \"evidence\": \"Xenopus egg extract biochemistry, domain mutagenesis, reciprocal Co-IP, validated in human cells\",\n      \"pmids\": [\"20188555\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"ATM dephosphorylation sites not pinpointed\", \"Physiological context where this suppression dominates not defined\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Identified the histone H3 substrates of the complex and connected H3T3ph reversal to Aurora B centromeric targeting, linking phosphatase activity to kinase positioning.\",\n      \"evidence\": \"In vitro phosphatase assays, RNAi, mutagenesis, and Aurora B/MCAK localization imaging\",\n      \"pmids\": [\"21514157\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct versus indirect dephosphorylation of H3S10/H3T11 not fully separated\", \"Quantitative contribution to Aurora B gradient unresolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Resolved the protein into two separable functional modules \\u2014 a chromatin-targeting/H3-dephosphorylating C-terminus and a PP1-independent nuclear envelope-recruiting N-terminus \\u2014 explaining its dual roles at mitotic exit.\",\n      \"evidence\": \"Domain deletion/mutation, live-cell imaging, Co-IP, and fractionation\",\n      \"pmids\": [\"21820363\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How the two domains are temporally coordinated within anaphase unclear\", \"Structural basis of Importin \\u03b2/Nup153 recruitment not defined\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Showed Repo-Man (with Sds22) counteracts Aurora B phosphorylation of the kinetochore component Dsn1, tying its activity to faithful chromosome segregation.\",\n      \"evidence\": \"Phosphorylation-biosensor RNAi screen and live-cell imaging\",\n      \"pmids\": [\"22801782\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct dephosphorylation of Dsn1 not biochemically demonstrated\", \"Relative contributions of Repo-Man and Sds22 not separated\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Defined the phospho-switch governing Repo-Man recruitment: Aurora B phosphorylation at S893 blocks chromatin targeting and PP2A reverses it, establishing a bistable kinase/phosphatase feedback loop.\",\n      \"evidence\": \"S893 mutagenesis, in vitro kinase assay, reciprocal Co-IP, and functional rescue\",\n      \"pmids\": [\"23746640\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Quantitative thresholds of the bistable switch not modeled\", \"Whether other Aurora B sites contribute not excluded\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Provided cancer-relevant loss-of-function evidence that CDCA2 prevents ATM-dependent p53-p21 signaling and supports proliferation, connecting its checkpoint-suppressing role to tumor cell survival.\",\n      \"evidence\": \"shRNA knockdown with cell-cycle flow cytometry and CDK-inhibitor Western blots in oral squamous carcinoma cells\",\n      \"pmids\": [\"23418564\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct link between CDCA2 phosphatase activity and p21/p27 induction not biochemically shown\", \"Single cancer cell context\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Demonstrated an interphase chromatin role: Repo-Man/PP1 dephosphorylates H3S28 at the nuclear periphery to promote HP1 binding, H3K27me3 recruitment, and heterochromatin organization.\",\n      \"evidence\": \"ChIP-seq, RNAi, immunofluorescence, and gene-expression readouts\",\n      \"pmids\": [\"28091603\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism coupling Nup153 anchoring to substrate selection unclear\", \"Causality between H3S28 dephosphorylation and H3K27me3 deposition not fully dissected\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Linked Repo-Man/PP1 to spindle orientation through cortical NuMA accumulation, with p37/UBXN2B as a negative regulator, broadening its mitotic remit beyond chromatin.\",\n      \"evidence\": \"RNAi, immunofluorescence, live-cell imaging, and epistasis with G\\u03b1i/Aurora A/PP2A inhibitors\",\n      \"pmids\": [\"29222185\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct phosphatase substrate at the cortex not identified\", \"Mechanism by which p37 inhibits the complex undefined\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Reinforced that Aurora B phosphorylation disrupts the PP1\\u03b3-Repo-Man interaction itself, controlling chromosome condensation dynamics through PP1\\u03b3 retention.\",\n      \"evidence\": \"Co-IP, phospho-resistant mutant overexpression, Aurora B inhibition, and immunofluorescence\",\n      \"pmids\": [\"32938714\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab confirmation of S893-specific effect on PP1\\u03b3 binding\", \"Structural basis of phospho-disrupted PP1 binding unknown\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified lamin A S22 as a mitotic-exit substrate and SUMOylation of Repo-Man as the targeting mechanism, mechanistically connecting the complex to nuclear envelope reformation.\",\n      \"evidence\": \"In vitro/in vivo Co-IP, SUMOylation-deficient mutant rescue, phospho-specific Western blots, and NE-defect imaging\",\n      \"pmids\": [\"35414260\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"SUMO sites on Repo-Man not mapped\", \"Whether SUMOylation regulates other substrate interactions unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Revealed a tumor-promoting mechanism in which CDCA2 stabilizes AURKA by acting on the E3 ligase SMURF1 to block its ubiquitin-dependent degradation, driving melanoma proliferation.\",\n      \"evidence\": \"Co-IP, ubiquitination and protein stability assays, epistasis, and in vitro/in vivo tumor models\",\n      \"pmids\": [\"37196484\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether PP1 phosphatase activity is required for AURKA stabilization unclear\", \"Direct CDCA2-SMURF1 biochemical mechanism incompletely defined\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Established CDCA2 as both a stabilizer of MYC/MYCN proteins and a direct MYC target gene, defining an oncogenic positive feedback loop whose disruption reduces tumor cell viability.\",\n      \"evidence\": \"RNAi, degron degradation, proximity ligation, ChIP, and promoter mutation studies across multiple cancer cell types\",\n      \"pmids\": [\"41844234\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which CDCA2 stabilizes MYC/MYCN not biochemically resolved\", \"Whether stabilization depends on PP1 or phosphatase activity unknown\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Showed PHD1-mediated prolyl hydroxylation of Repo-Man at P604 is required for PP2A-B56\\u03b3 interaction and proper mitotic progression, adding a PTM-controlled layer to phosphatase complex assembly.\",\n      \"evidence\": \"Mass spectrometry PTM identification, P604A mutant rescue, Co-IP for PP2A-B56\\u03b3, and live-cell imaging (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.05.06.652400\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, single lab not yet peer-reviewed\", \"How oxygen-sensitive hydroxylation integrates with the Aurora B/PP2A switch unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How CDCA2's well-defined mitotic phosphatase-targeting activity mechanistically connects to its oncogenic MYC/MYCN and AURKA stabilization functions \\u2014 and whether these depend on PP1 catalytic activity \\u2014 remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the chromatin-bound PP1\\u03b3/Repo-Man complex\", \"Biochemical mechanism of MYC/MYCN and AURKA protein stabilization undefined\", \"Whether oncogenic roles require phosphatase activity untested\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 4, 6]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 4]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3, 2, 11]},\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [3, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [0, 3, 4]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [9]},\n      {\"term_id\": \"GO:0005635\", \"supporting_discovery_ids\": [4, 11]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 9]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [0, 1, 3, 4, 6]},\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [3, 9]},\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [12, 13]}\n    ],\n    \"complexes\": [\n      \"PP1\\u03b3/Repo-Man complex\"\n    ],\n    \"partners\": [\n      \"PPP1CC\",\n      \"ATM\",\n      \"Nup153\",\n      \"KPNB1\",\n      \"AURKB\",\n      \"LMNA\",\n      \"MYC\",\n      \"MYCN\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}