{"gene":"CCNB1IP1","run_date":"2026-06-09T22:57:17","timeline":{"discoveries":[{"year":2026,"finding":"Human HEI10 (CCNB1IP1) has E3-ubiquitin ligase activity that depends on its higher-order assembly. Crystal structure reveals a 29-nm rod-like tetramer formed through head-to-head association of two coiled-coil dimers, clustering four RING domains at the molecular centre. HEI10 tetramers self-assemble into fibrous and spherical higher-order structures via RING, coiled-coil, and C-terminal interfaces. Structure-guided mutants show higher-order assembly is required for HEI10 to catalyse K63-linked ubiquitin chain formation in vitro.","method":"Crystal structure determination, in vitro ubiquitin ligase assay, structure-guided mutagenesis","journal":"bioRxiv","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with functional validation by mutagenesis and in vitro reconstitution of E3 ligase activity in single rigorous study","pmids":["42146605"],"is_preprint":true},{"year":2007,"finding":"Mouse HEI10 (Ccnb1ip1/mei4) is required for meiotic crossing over; loss-of-function causes absence of chiasmata, failure of CDK2 and mismatch repair protein association with chromosome cores, premature bivalent separation at diplotene, and sterility in both sexes. The protein is identified as a putative B-type cyclin E3 ubiquitin ligase.","method":"ENU mutagenesis, genetic mapping, splice-site mutation characterisation, cytological analysis of spermatocytes/oocytes","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean loss-of-function allele with defined cellular phenotype, replicated across sexes, molecular cause identified","pmids":["17784788"],"is_preprint":false},{"year":2012,"finding":"Rice HEI10 is required specifically for class I (interference-sensitive) crossover formation but not for early recombination events or synaptonemal complex assembly. HEI10 protein first appears as foci co-localising with MER3, then extends as linear signals along ZEP1-marked SC central regions, and finally restricts to prominent foci at chiasma sites, indicating a dynamic role in crossover intermediate maturation.","method":"Map-based cloning, immunolocalisation on meiotic chromosomes, cytological analysis of hei10 mutant","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct localisation with functional consequence in clean loss-of-function mutant, multiple cytological methods","pmids":["22792078"],"is_preprint":false},{"year":2010,"finding":"CCNB1IP1 protein appears on meiotic chromosomes during pachynema (not leptotene), implicating it in crossover intermediate maturation rather than early DSB specification. Yeast two-hybrid screen identified interaction with SUMO2 and proteins enriched for sumoylation consensus sites, suggesting CCNB1IP1 functions as an E3 SUMO ligase in meiotic cells.","method":"Immunofluorescence with specific antibody (localization), yeast two-hybrid screen","journal":"Genes","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — direct localisation experiment plus Y2H interaction screen; SUMO E3 ligase activity inferred but not biochemically reconstituted","pmids":["21779533"],"is_preprint":false},{"year":2014,"finding":"In Sordaria, Hei10 makes three successive types of foci along SC central regions. The RING domain mediates development and turnover of sequential recombination complexes and positively modulates SUMO localisation along SCs. The RXL (putative cyclin-binding) domain negatively modulates SUMO localisation. Null, RING-binding, and RXL domain mutants show distinct defects, establishing that both domains are required for Hei10's pro-crossover function.","method":"Null and domain-specific mutant analysis (RING, RXL), immunolocalisation, ultrastructural analysis of recombination nodules","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 2 / Strong — domain-specific mutagenesis with multiple orthogonal readouts (localisation, SUMO modulation, nodule ultrastructure) in a single rigorous study","pmids":["24831702"],"is_preprint":false},{"year":2007,"finding":"HEI10 depletion in human cells increases cell migration and invasion and post-transcriptionally upregulates promotility proteins including p130Cas, paxillin, Cdk1, and cyclin B2. Specific inhibition of Cdk1/cyclin B activity reverses the motility and invasion phenotype of HEI10-depleted cells, placing HEI10 upstream of cyclin B/Cdk1 in suppressing cell invasion.","method":"siRNA knockdown, migration/invasion assays, immunoblotting, pharmacological inhibition of Cdk1/cyclin B","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function with defined phenotypic readout and epistasis experiment (Cdk1 inhibitor rescue), single lab","pmids":["17297447"],"is_preprint":false},{"year":2006,"finding":"HEI10 physically interacts with the tumor suppressor merlin (NF2); the interaction is mediated by the alpha-helical domain of merlin and the coiled-coil domain of HEI10 and requires conformational opening of merlin. HEI10 and merlin show partial cell cycle-dependent and adhesion-dependent subcellular co-localisation. Expression of a constitutively open merlin construct affects HEI10 protein integrity.","method":"Co-immunoprecipitation, domain-mapping, immunofluorescence co-localisation, transfection of constitutively open merlin","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — reciprocal binding and domain mapping demonstrated, single lab, multiple methods","pmids":["16532029"],"is_preprint":false},{"year":2023,"finding":"Arabidopsis HEI10 forms foci on chromatin via liquid-liquid phase separation (LLPS) dependent on residue Ser70; a HEI10S70F allele abolishes LLPS and class I CO formation. HEI10 ubiquitinates RPA1a (identified by immunoprecipitation-mass spectrometry as a HEI10-interacting protein), promoting RPA1a degradation. HEI10 is also required for condensation of other class I CO factors.","method":"LLPS assay, site-directed mutagenesis (Ser70Phe), immunoprecipitation-mass spectrometry, ubiquitination assay, immunolocalisation","journal":"PNAS","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vitro LLPS reconstitution, mutagenesis, MS-identified substrate, ubiquitination assay, multiple orthogonal methods in single study","pmids":["38134200"],"is_preprint":false},{"year":2023,"finding":"CCNB1IP1 physically interacts with MYCN (co-immunoprecipitation), protects MYCN from ubiquitination-mediated degradation by competing with FBXW7 for MYCN binding, and does so in a C-terminal domain-dependent manner. MYCN in turn directly transcribes CCNB1IP1 (ChIP + luciferase assay), establishing a positive feedback loop.","method":"Co-immunoprecipitation, ubiquitination IP assay, dual-luciferase reporter, chromatin immunoprecipitation, gain/loss-of-function experiments","journal":"Clinical and translational medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, ubiquitination assay, and ChIP in single lab; multiple orthogonal methods","pmids":["37461251"],"is_preprint":false},{"year":2025,"finding":"CCNB1IP1 regulates ubiquitination and degradation of cyclin B1, modulating G2/M phase arrest after radiation. ESR1 (estrogen receptor 1) acts as a transcription factor that inhibits CCNB1IP1 transcription; AdipoR1 promotes ESR1 nuclear translocation, thereby suppressing CCNB1IP1 and increasing cyclin B1 levels.","method":"Ubiquitination IP assay, rescue experiment, transcription factor database analysis combined with AdipoR1 transcriptome sequencing, nuclear translocation imaging","journal":"Molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ubiquitination assay with rescue, transcriptional regulation confirmed, single lab with multiple methods","pmids":["39849382"],"is_preprint":false},{"year":2022,"finding":"Overexpression of HEI10 in Arabidopsis increases crossover number while maintaining interference and sexual dimorphism. Combining HEI10 overexpression with zyp1 (synaptonemal complex) mutation produces a massive synergistic increase in crossovers, supporting a model in which HEI10 diffusion along the SC drives a coarsening process that spaces crossover-promoting foci.","method":"HEI10 overexpression lines, genetic analysis of crossover number and interference, double-mutant epistasis (HEI10-OE × zyp1)","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis with quantitative crossover phenotype, HEI10 overexpression and synaptonemal complex mutant combination, replicated observations","pmids":["36224180"],"is_preprint":false},{"year":2024,"finding":"Rice HEI10 containing a point mutation (Leu→Phe, HEI10tfs2) fails to form nuclear dot-like aggregates at high temperature, resulting in univalent formation and meiotic failure; aggregation is restored at low temperature, restoring fertility. Yeast two-hybrid assays showed HEI10 interacts with RPT4 and SRFP1 (proteasome/ubiquitin-related proteins); aggregation of RPT4 and SRFP1 into foci also depends on HEI10.","method":"EMS mutagenesis, genetic complementation, transient expression aggregation assay (tobacco), yeast two-hybrid","journal":"The Plant journal","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — aggregation assay directly links protein condensation to CO function; Y2H identifies new interactors; single lab","pmids":["38169508"],"is_preprint":false},{"year":2024,"finding":"Rice HEI10 truncated at its N-terminus (lacking the RING domain, sh1 allele) localises correctly to the nucleus and retains protein-protein interaction capacity sufficient to partially restore female fertility in hei10 null lines, but completely fails to support male fertility, demonstrating that the RING domain is essential for male but not female meiosis.","method":"Genetic complementation, allelic tests, nuclear localisation imaging, fertility assays in hei10 null background","journal":"Rice","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — domain loss-of-function with sex-specific phenotypic rescue in clean null background, single lab","pmids":["38180592"],"is_preprint":false},{"year":2025,"finding":"Mouse HEIP1 directly interacts with HEI10 (co-immunoprecipitation) and is required to recruit HEI10, RNF212, and RNF212B to meiotic chromosomes; loss of HEIP1 abolishes crossovers and causes sterility in both sexes, placing HEIP1 upstream of HEI10 in the pro-crossover pathway.","method":"Co-immunoprecipitation, immunolocalisation in Heip1 knockout, genetic analysis of fertility","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal interaction and epistasis established in clean KO, single lab, preprint","pmids":["bio_10.1101_2025.08.25.672081"],"is_preprint":true},{"year":2001,"finding":"In a uterine leiomyoma, HEI10 (at 14q11) is fused to the HMGIC gene (at 12q15) such that the first two exons of HMGIC (encoding DNA-binding domains) are joined to the 3' portion of HEI10, identifying HEI10 as a chromosomal translocation partner.","method":"3' RACE cloning of fusion cDNA, radiation hybrid mapping","journal":"Japanese journal of cancer research","confidence":"Low","confidence_rationale":"Tier 3 / Weak — identifies chromosomal fusion partner but provides no direct functional mechanism for HEI10 itself","pmids":["11223542"],"is_preprint":false}],"current_model":"CCNB1IP1/HEI10 is a RING-domain E3 ubiquitin (and likely SUMO) ligase that forms a 29-nm tetrameric core through coiled-coil dimerisation, enabling higher-order self-assembly required for K63-linked ubiquitin chain formation; during meiosis it undergoes liquid-liquid phase separation (dependent on Ser70) to load onto synaptonemal complex central regions, diffuses and coarsens into discrete foci at future class I crossover sites where it ubiquitinates substrates including RPA1a, and requires its RING domain to promote interference-sensitive crossover maturation while its RXL domain modulates SUMO distribution along the SC; outside meiosis, it suppresses cell invasion by targeting cyclin B/CDK1 for degradation downstream of merlin binding, and in cancer cells it protects MYCN from FBXW7-mediated ubiquitination via a positive transcriptional feedback loop."},"narrative":{"mechanistic_narrative":"CCNB1IP1 (HEI10) is a RING-domain E3 ubiquitin ligase that governs class I (interference-sensitive) crossover formation during meiosis and modulates cyclin B/CDK1 activity in somatic cells [PMID:17784788, PMID:22792078, PMID:17297447]. Its catalytic activity is coupled to higher-order self-assembly: a 29-nm rod-like tetramer forms through head-to-head association of two coiled-coil dimers, clustering four RING domains at its centre, and this assembly is required to catalyse K63-linked ubiquitin chains in vitro [PMID:42146605]. In meiosis the protein appears on chromosomes during pachynema rather than at early DSB stages, progressing from foci that co-localise with recombination markers to linear signals along the synaptonemal complex central region and finally to discrete foci at future chiasma sites [PMID:22792078, PMID:21779533]. Focus formation depends on liquid-liquid phase separation governed by residue Ser70, and HEI10 diffusion along the SC drives a coarsening process that spaces crossover-promoting foci while preserving interference; ubiquitination of the recombination factor RPA1a is one downstream event promoting its degradation [PMID:38134200, PMID:36224180]. The RING domain mediates the maturation and turnover of sequential recombination complexes and is essential for male but not female meiosis, while the RXL (putative cyclin-binding) domain oppositely modulates SUMO localisation along the SC, and recruitment to chromosomes requires the upstream partner HEIP1 [PMID:24831702, PMID:38180592, PMID:bio_10.1101_2025.08.25.672081]. Outside meiosis, HEI10 suppresses cell migration and invasion by acting upstream of cyclin B/CDK1, an activity linked to its interaction with the tumor suppressor merlin (NF2), and it controls cyclin B1 ubiquitination and degradation in the G2/M radiation response [PMID:17297447, PMID:16532029, PMID:39849382]. In neuroblastoma cells it protects MYCN from FBXW7-mediated degradation within a positive transcriptional feedback loop [PMID:37461251]. Loss of HEI10 abolishes chiasmata and causes sterility in both sexes [PMID:17784788].","teleology":[{"year":2001,"claim":"Identifying HEI10 as a chromosomal translocation partner gave the first hint of a disease association before any functional role was known.","evidence":"3' RACE cloning of an HMGIC-HEI10 fusion cDNA from uterine leiomyoma with radiation hybrid mapping","pmids":["11223542"],"confidence":"Low","gaps":["Provides no functional mechanism for HEI10 itself","Causal role of the fusion in tumorigenesis not established"]},{"year":2006,"claim":"Discovery of a direct merlin (NF2) interaction placed HEI10 in a tumor-suppressor signalling context and mapped the binding interfaces.","evidence":"Co-immunoprecipitation, domain mapping, and co-localisation with constitutively open merlin in human cells","pmids":["16532029"],"confidence":"Medium","gaps":["Functional consequence of the interaction left unresolved","Single lab without reciprocal in vivo validation"]},{"year":2007,"claim":"Two independent lines of evidence established HEI10 both as an essential meiotic crossover factor and as a somatic suppressor of cell invasion acting through cyclin B/CDK1.","evidence":"ENU mutant cytological analysis of mouse spermatocytes/oocytes; siRNA knockdown with migration/invasion assays and Cdk1/cyclin B inhibitor rescue in human cells","pmids":["17784788","17297447"],"confidence":"High","gaps":["Direct ubiquitin ligase activity not biochemically demonstrated","Substrate of the proposed cyclin B ligase activity not identified","Molecular link between merlin and the cyclin B axis untested"]},{"year":2010,"claim":"Pachytene-stage chromosome loading plus a SUMO2 interaction screen reframed HEI10 as a crossover-maturation factor potentially acting as a SUMO ligase.","evidence":"Immunofluorescence localisation with specific antibody and yeast two-hybrid screen against sumoylation-consensus proteins","pmids":["21779533"],"confidence":"Medium","gaps":["SUMO E3 ligase activity inferred but not reconstituted","Y2H interactions not validated by reciprocal binding"]},{"year":2012,"claim":"Rice work pinned HEI10 specifically to the class I crossover pathway and revealed its dynamic focus-to-line-to-focus localisation pattern.","evidence":"Map-based cloning and immunolocalisation on meiotic chromosomes in a hei10 null mutant","pmids":["22792078"],"confidence":"High","gaps":["Mechanism converting linear signal to discrete foci unknown","Substrates ubiquitinated during maturation not identified"]},{"year":2014,"claim":"Domain-specific mutagenesis dissected opposing roles of the RING and RXL domains in recombination-complex turnover and SUMO distribution.","evidence":"Null, RING-binding, and RXL domain mutant analysis with immunolocalisation and recombination nodule ultrastructure in Sordaria","pmids":["24831702"],"confidence":"High","gaps":["Direct catalytic targets of the RING domain not defined","Biochemical basis of RXL-dependent SUMO modulation unresolved"]},{"year":2022,"claim":"Genetic epistasis showed HEI10 dosage and SC diffusion drive a coarsening process that sets crossover number and spacing.","evidence":"HEI10 overexpression lines and HEI10-OE x zyp1 double-mutant crossover/interference analysis in Arabidopsis","pmids":["36224180"],"confidence":"High","gaps":["Physical mechanism of coarsening not directly observed","Conservation of dosage effect in animals untested"]},{"year":2023,"claim":"Phase separation and substrate identification connected HEI10 condensation to its catalytic crossover function and to MYCN stability in cancer.","evidence":"LLPS assay, Ser70Phe mutagenesis, IP-MS, and ubiquitination assay in Arabidopsis; Co-IP, ubiquitination IP, ChIP, and luciferase reporter in neuroblastoma cells","pmids":["38134200","37461251"],"confidence":"High","gaps":["Whether RPA1a ubiquitination is conserved beyond plants unknown","Direct catalytic basis of MYCN protection (competition vs. enzymatic) not fully separated"]},{"year":2024,"claim":"Condensation requirement, sex-specific RING dependence, and new interactors refined how HEI10 assembly and partners drive meiosis.","evidence":"Temperature-sensitive aggregation mutant (HEI10tfs2) and RING-truncation complementation in rice with Y2H against RPT4/SRFP1","pmids":["38169508","38180592"],"confidence":"Medium","gaps":["Basis of sex-specific RING requirement unexplained","RPT4/SRFP1 interactions not validated beyond Y2H"]},{"year":2025,"claim":"Identification of upstream regulators and a radiation-response substrate connected HEI10 recruitment and cyclin B1 control to physiological pathways.","evidence":"Heip1 knockout immunolocalisation and Co-IP in mouse; ubiquitination IP with rescue and ESR1/AdipoR1 transcriptional analysis in somatic cells","pmids":["bio_10.1101_2025.08.25.672081","39849382"],"confidence":"Medium","gaps":["Mechanism by which HEIP1 nucleates HEI10/RNF212 loading unresolved","HEIP1 finding is a preprint awaiting peer review","Direct cyclin B1 ubiquitination by HEI10 versus indirect effect not fully separated"]},{"year":2026,"claim":"A crystal structure established the architectural basis linking higher-order self-assembly to E3 ligase catalysis.","evidence":"Crystal structure, structure-guided mutagenesis, and in vitro ubiquitin ligase assay of human HEI10 (preprint)","pmids":["42146605"],"confidence":"High","gaps":["Whether meiotic foci adopt the same tetrameric architecture in vivo untested","Substrate-specifying determinants of the assembled ligase not defined"]},{"year":null,"claim":"How HEI10's catalytic assembly, phase separation, and substrate choice are integrated to select discrete crossover sites and how these mechanisms translate to its somatic cyclin B/MYCN roles remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking in vitro tetramer assembly to in vivo foci","Full substrate repertoire of the E3 ligase undefined","Relationship between meiotic and oncogenic functions unestablished"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[0,7]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,7,8,9]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[8,5]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[3,11,12]},{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[2,3,7]}],"pathway":[{"term_id":"R-HSA-1474165","term_label":"Reproduction","supporting_discovery_ids":[1,2,10]},{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[5,9]},{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,7,8]}],"complexes":["synaptonemal complex central region"],"partners":["NF2","MYCN","FBXW7","RPA1A","HEIP1","RNF212","RPT4","SRFP1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9NPC3","full_name":"E3 ubiquitin-protein ligase CCNB1IP1","aliases":["Cyclin-B1-interacting protein 1","Human enhancer of invasion 10","RING-type E3 ubiquitin transferase CCNB1IP1"],"length_aa":277,"mass_kda":31.5,"function":"Ubiquitin E3 ligase that acts as a limiting factor for crossing-over during meiosis: required during zygonema to limit the colocalization of RNF212 with MutS-gamma-associated recombination sites and thereby establish early differentiation of crossover and non-crossover sites. Later, it is directed by MutL-gamma to stably accumulate at designated crossover sites. Probably promotes the dissociation of RNF212 and MutS-gamma to allow the progression of recombination and the implementation of the final steps of crossing over (By similarity). Modulates cyclin-B levels and participates in the regulation of cell cycle progression through the G2 phase. Overexpression causes delayed entry into mitosis","subcellular_location":"Nucleus; Chromosome","url":"https://www.uniprot.org/uniprotkb/Q9NPC3/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CCNB1IP1","classification":"Not Classified","n_dependent_lines":98,"n_total_lines":1208,"dependency_fraction":0.08112582781456953},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CCNB1IP1","total_profiled":1310},"omim":[{"mim_id":"621020","title":"RING FINGER PROTEIN 212B; RNF212B","url":"https://www.omim.org/entry/621020"},{"mim_id":"620495","title":"REGULATOR OF DNA CLASS I CROSSOVER INTERMEDIATES 1; REDIC1","url":"https://www.omim.org/entry/620495"},{"mim_id":"618166","title":"CYCLIN N-TERMINAL DOMAIN-CONTAINING PROTEIN 1; CNTD1","url":"https://www.omim.org/entry/618166"},{"mim_id":"612041","title":"RING FINGER PROTEIN 212; RNF212","url":"https://www.omim.org/entry/612041"},{"mim_id":"608249","title":"CYCLIN B1 INTERACTING PROTEIN 1; CCNB1IP1","url":"https://www.omim.org/entry/608249"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/CCNB1IP1"},"hgnc":{"alias_symbol":["HEI10"],"prev_symbol":["C14orf18"]},"alphafold":{"accession":"Q9NPC3","domains":[{"cath_id":"3.30.40.10","chopping":"7-76","consensus_level":"medium","plddt":94.6726,"start":7,"end":76}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NPC3","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NPC3-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NPC3-F1-predicted_aligned_error_v6.png","plddt_mean":76.88},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CCNB1IP1","jax_strain_url":"https://www.jax.org/strain/search?query=CCNB1IP1"},"sequence":{"accession":"Q9NPC3","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9NPC3.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9NPC3/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NPC3"}},"corpus_meta":[{"pmid":"22792078","id":"PMC_22792078","title":"The role of rice HEI10 in the formation of meiotic crossovers.","date":"2012","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/22792078","citation_count":120,"is_preprint":false},{"pmid":"17784788","id":"PMC_17784788","title":"Mutation in mouse hei10, an e3 ubiquitin ligase, disrupts meiotic crossing over.","date":"2007","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/17784788","citation_count":100,"is_preprint":false},{"pmid":"24831702","id":"PMC_24831702","title":"E3 ligase Hei10: a multifaceted structure-based signaling molecule with roles within and beyond meiosis.","date":"2014","source":"Genes & development","url":"https://pubmed.ncbi.nlm.nih.gov/24831702","citation_count":85,"is_preprint":false},{"pmid":"36224180","id":"PMC_36224180","title":"Joint control of meiotic crossover patterning by the synaptonemal complex and HEI10 dosage.","date":"2022","source":"Nature 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Gann","url":"https://pubmed.ncbi.nlm.nih.gov/11223542","citation_count":31,"is_preprint":false},{"pmid":"16532029","id":"PMC_16532029","title":"A functional association between merlin and HEI10, a cell cycle regulator.","date":"2006","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/16532029","citation_count":24,"is_preprint":false},{"pmid":"38134200","id":"PMC_38134200","title":"HEI10 is subject to phase separation and mediates RPA1a degradation during meiotic interference-sensitive crossover formation.","date":"2023","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/38134200","citation_count":10,"is_preprint":false},{"pmid":"38838583","id":"PMC_38838583","title":"HEI10 coarsening, chromatin and sequence polymorphism shape the plant meiotic recombination landscape.","date":"2024","source":"Current opinion in plant 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N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/38180592","citation_count":1,"is_preprint":false},{"pmid":"39849382","id":"PMC_39849382","title":"AdipoR1 enhances the radiation resistance via ESR1/CCNB1IP1/cyclin B1 pathway in hepatocellular carcinoma cells.","date":"2025","source":"Molecular medicine (Cambridge, Mass.)","url":"https://pubmed.ncbi.nlm.nih.gov/39849382","citation_count":1,"is_preprint":false},{"pmid":"42146605","id":"PMC_42146605","title":"Molecular architecture of meiotic pro-crossover factor HEI10 reveals coupling of higher-order assembly and ubiquitin chain formation.","date":"2026","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/42146605","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.04.02.25325097","title":"Common variation in meiosis genes shapes human recombination phenotypes and aneuploidy risk","date":"2025-04-04","source":"bioRxiv","url":"https://doi.org/10.1101/2025.04.02.25325097","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.06.20.599484","title":"Individual variation in meiotic crossover positioning, rate and interference are associated with distinct genetic processes in domestic pigs","date":"2024-06-24","source":"bioRxiv","url":"https://doi.org/10.1101/2024.06.20.599484","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.08.25.672081","title":"HEIP1 orchestrates pro-crossover protein activity during mammalian meiosis","date":"2025-08-28","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.25.672081","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.08.08.669263","title":"Sex chromosome pairing and multivalent associations during meiosis in diploid and polyploid  <i>Silene latifolia</i>","date":"2025-08-11","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.08.669263","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12175,"output_tokens":3938,"usd":0.047797,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11695,"output_tokens":3835,"usd":0.077175,"stage2_stop_reason":"end_turn"},"total_usd":0.124972,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2026,\n      \"finding\": \"Human HEI10 (CCNB1IP1) has E3-ubiquitin ligase activity that depends on its higher-order assembly. Crystal structure reveals a 29-nm rod-like tetramer formed through head-to-head association of two coiled-coil dimers, clustering four RING domains at the molecular centre. HEI10 tetramers self-assemble into fibrous and spherical higher-order structures via RING, coiled-coil, and C-terminal interfaces. Structure-guided mutants show higher-order assembly is required for HEI10 to catalyse K63-linked ubiquitin chain formation in vitro.\",\n      \"method\": \"Crystal structure determination, in vitro ubiquitin ligase assay, structure-guided mutagenesis\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with functional validation by mutagenesis and in vitro reconstitution of E3 ligase activity in single rigorous study\",\n      \"pmids\": [\"42146605\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Mouse HEI10 (Ccnb1ip1/mei4) is required for meiotic crossing over; loss-of-function causes absence of chiasmata, failure of CDK2 and mismatch repair protein association with chromosome cores, premature bivalent separation at diplotene, and sterility in both sexes. The protein is identified as a putative B-type cyclin E3 ubiquitin ligase.\",\n      \"method\": \"ENU mutagenesis, genetic mapping, splice-site mutation characterisation, cytological analysis of spermatocytes/oocytes\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean loss-of-function allele with defined cellular phenotype, replicated across sexes, molecular cause identified\",\n      \"pmids\": [\"17784788\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Rice HEI10 is required specifically for class I (interference-sensitive) crossover formation but not for early recombination events or synaptonemal complex assembly. HEI10 protein first appears as foci co-localising with MER3, then extends as linear signals along ZEP1-marked SC central regions, and finally restricts to prominent foci at chiasma sites, indicating a dynamic role in crossover intermediate maturation.\",\n      \"method\": \"Map-based cloning, immunolocalisation on meiotic chromosomes, cytological analysis of hei10 mutant\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct localisation with functional consequence in clean loss-of-function mutant, multiple cytological methods\",\n      \"pmids\": [\"22792078\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"CCNB1IP1 protein appears on meiotic chromosomes during pachynema (not leptotene), implicating it in crossover intermediate maturation rather than early DSB specification. Yeast two-hybrid screen identified interaction with SUMO2 and proteins enriched for sumoylation consensus sites, suggesting CCNB1IP1 functions as an E3 SUMO ligase in meiotic cells.\",\n      \"method\": \"Immunofluorescence with specific antibody (localization), yeast two-hybrid screen\",\n      \"journal\": \"Genes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — direct localisation experiment plus Y2H interaction screen; SUMO E3 ligase activity inferred but not biochemically reconstituted\",\n      \"pmids\": [\"21779533\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"In Sordaria, Hei10 makes three successive types of foci along SC central regions. The RING domain mediates development and turnover of sequential recombination complexes and positively modulates SUMO localisation along SCs. The RXL (putative cyclin-binding) domain negatively modulates SUMO localisation. Null, RING-binding, and RXL domain mutants show distinct defects, establishing that both domains are required for Hei10's pro-crossover function.\",\n      \"method\": \"Null and domain-specific mutant analysis (RING, RXL), immunolocalisation, ultrastructural analysis of recombination nodules\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — domain-specific mutagenesis with multiple orthogonal readouts (localisation, SUMO modulation, nodule ultrastructure) in a single rigorous study\",\n      \"pmids\": [\"24831702\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"HEI10 depletion in human cells increases cell migration and invasion and post-transcriptionally upregulates promotility proteins including p130Cas, paxillin, Cdk1, and cyclin B2. Specific inhibition of Cdk1/cyclin B activity reverses the motility and invasion phenotype of HEI10-depleted cells, placing HEI10 upstream of cyclin B/Cdk1 in suppressing cell invasion.\",\n      \"method\": \"siRNA knockdown, migration/invasion assays, immunoblotting, pharmacological inhibition of Cdk1/cyclin B\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function with defined phenotypic readout and epistasis experiment (Cdk1 inhibitor rescue), single lab\",\n      \"pmids\": [\"17297447\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"HEI10 physically interacts with the tumor suppressor merlin (NF2); the interaction is mediated by the alpha-helical domain of merlin and the coiled-coil domain of HEI10 and requires conformational opening of merlin. HEI10 and merlin show partial cell cycle-dependent and adhesion-dependent subcellular co-localisation. Expression of a constitutively open merlin construct affects HEI10 protein integrity.\",\n      \"method\": \"Co-immunoprecipitation, domain-mapping, immunofluorescence co-localisation, transfection of constitutively open merlin\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — reciprocal binding and domain mapping demonstrated, single lab, multiple methods\",\n      \"pmids\": [\"16532029\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Arabidopsis HEI10 forms foci on chromatin via liquid-liquid phase separation (LLPS) dependent on residue Ser70; a HEI10S70F allele abolishes LLPS and class I CO formation. HEI10 ubiquitinates RPA1a (identified by immunoprecipitation-mass spectrometry as a HEI10-interacting protein), promoting RPA1a degradation. HEI10 is also required for condensation of other class I CO factors.\",\n      \"method\": \"LLPS assay, site-directed mutagenesis (Ser70Phe), immunoprecipitation-mass spectrometry, ubiquitination assay, immunolocalisation\",\n      \"journal\": \"PNAS\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vitro LLPS reconstitution, mutagenesis, MS-identified substrate, ubiquitination assay, multiple orthogonal methods in single study\",\n      \"pmids\": [\"38134200\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CCNB1IP1 physically interacts with MYCN (co-immunoprecipitation), protects MYCN from ubiquitination-mediated degradation by competing with FBXW7 for MYCN binding, and does so in a C-terminal domain-dependent manner. MYCN in turn directly transcribes CCNB1IP1 (ChIP + luciferase assay), establishing a positive feedback loop.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination IP assay, dual-luciferase reporter, chromatin immunoprecipitation, gain/loss-of-function experiments\",\n      \"journal\": \"Clinical and translational medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, ubiquitination assay, and ChIP in single lab; multiple orthogonal methods\",\n      \"pmids\": [\"37461251\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CCNB1IP1 regulates ubiquitination and degradation of cyclin B1, modulating G2/M phase arrest after radiation. ESR1 (estrogen receptor 1) acts as a transcription factor that inhibits CCNB1IP1 transcription; AdipoR1 promotes ESR1 nuclear translocation, thereby suppressing CCNB1IP1 and increasing cyclin B1 levels.\",\n      \"method\": \"Ubiquitination IP assay, rescue experiment, transcription factor database analysis combined with AdipoR1 transcriptome sequencing, nuclear translocation imaging\",\n      \"journal\": \"Molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ubiquitination assay with rescue, transcriptional regulation confirmed, single lab with multiple methods\",\n      \"pmids\": [\"39849382\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Overexpression of HEI10 in Arabidopsis increases crossover number while maintaining interference and sexual dimorphism. Combining HEI10 overexpression with zyp1 (synaptonemal complex) mutation produces a massive synergistic increase in crossovers, supporting a model in which HEI10 diffusion along the SC drives a coarsening process that spaces crossover-promoting foci.\",\n      \"method\": \"HEI10 overexpression lines, genetic analysis of crossover number and interference, double-mutant epistasis (HEI10-OE × zyp1)\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis with quantitative crossover phenotype, HEI10 overexpression and synaptonemal complex mutant combination, replicated observations\",\n      \"pmids\": [\"36224180\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Rice HEI10 containing a point mutation (Leu→Phe, HEI10tfs2) fails to form nuclear dot-like aggregates at high temperature, resulting in univalent formation and meiotic failure; aggregation is restored at low temperature, restoring fertility. Yeast two-hybrid assays showed HEI10 interacts with RPT4 and SRFP1 (proteasome/ubiquitin-related proteins); aggregation of RPT4 and SRFP1 into foci also depends on HEI10.\",\n      \"method\": \"EMS mutagenesis, genetic complementation, transient expression aggregation assay (tobacco), yeast two-hybrid\",\n      \"journal\": \"The Plant journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — aggregation assay directly links protein condensation to CO function; Y2H identifies new interactors; single lab\",\n      \"pmids\": [\"38169508\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Rice HEI10 truncated at its N-terminus (lacking the RING domain, sh1 allele) localises correctly to the nucleus and retains protein-protein interaction capacity sufficient to partially restore female fertility in hei10 null lines, but completely fails to support male fertility, demonstrating that the RING domain is essential for male but not female meiosis.\",\n      \"method\": \"Genetic complementation, allelic tests, nuclear localisation imaging, fertility assays in hei10 null background\",\n      \"journal\": \"Rice\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain loss-of-function with sex-specific phenotypic rescue in clean null background, single lab\",\n      \"pmids\": [\"38180592\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Mouse HEIP1 directly interacts with HEI10 (co-immunoprecipitation) and is required to recruit HEI10, RNF212, and RNF212B to meiotic chromosomes; loss of HEIP1 abolishes crossovers and causes sterility in both sexes, placing HEIP1 upstream of HEI10 in the pro-crossover pathway.\",\n      \"method\": \"Co-immunoprecipitation, immunolocalisation in Heip1 knockout, genetic analysis of fertility\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal interaction and epistasis established in clean KO, single lab, preprint\",\n      \"pmids\": [\"bio_10.1101_2025.08.25.672081\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"In a uterine leiomyoma, HEI10 (at 14q11) is fused to the HMGIC gene (at 12q15) such that the first two exons of HMGIC (encoding DNA-binding domains) are joined to the 3' portion of HEI10, identifying HEI10 as a chromosomal translocation partner.\",\n      \"method\": \"3' RACE cloning of fusion cDNA, radiation hybrid mapping\",\n      \"journal\": \"Japanese journal of cancer research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — identifies chromosomal fusion partner but provides no direct functional mechanism for HEI10 itself\",\n      \"pmids\": [\"11223542\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CCNB1IP1/HEI10 is a RING-domain E3 ubiquitin (and likely SUMO) ligase that forms a 29-nm tetrameric core through coiled-coil dimerisation, enabling higher-order self-assembly required for K63-linked ubiquitin chain formation; during meiosis it undergoes liquid-liquid phase separation (dependent on Ser70) to load onto synaptonemal complex central regions, diffuses and coarsens into discrete foci at future class I crossover sites where it ubiquitinates substrates including RPA1a, and requires its RING domain to promote interference-sensitive crossover maturation while its RXL domain modulates SUMO distribution along the SC; outside meiosis, it suppresses cell invasion by targeting cyclin B/CDK1 for degradation downstream of merlin binding, and in cancer cells it protects MYCN from FBXW7-mediated ubiquitination via a positive transcriptional feedback loop.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CCNB1IP1 (HEI10) is a RING-domain E3 ubiquitin ligase that governs class I (interference-sensitive) crossover formation during meiosis and modulates cyclin B/CDK1 activity in somatic cells [#1, #2, #5]. Its catalytic activity is coupled to higher-order self-assembly: a 29-nm rod-like tetramer forms through head-to-head association of two coiled-coil dimers, clustering four RING domains at its centre, and this assembly is required to catalyse K63-linked ubiquitin chains in vitro [#0]. In meiosis the protein appears on chromosomes during pachynema rather than at early DSB stages, progressing from foci that co-localise with recombination markers to linear signals along the synaptonemal complex central region and finally to discrete foci at future chiasma sites [#2, #3]. Focus formation depends on liquid-liquid phase separation governed by residue Ser70, and HEI10 diffusion along the SC drives a coarsening process that spaces crossover-promoting foci while preserving interference; ubiquitination of the recombination factor RPA1a is one downstream event promoting its degradation [#7, #10]. The RING domain mediates the maturation and turnover of sequential recombination complexes and is essential for male but not female meiosis, while the RXL (putative cyclin-binding) domain oppositely modulates SUMO localisation along the SC, and recruitment to chromosomes requires the upstream partner HEIP1 [#4, #12, #13]. Outside meiosis, HEI10 suppresses cell migration and invasion by acting upstream of cyclin B/CDK1, an activity linked to its interaction with the tumor suppressor merlin (NF2), and it controls cyclin B1 ubiquitination and degradation in the G2/M radiation response [#5, #6, #9]. In neuroblastoma cells it protects MYCN from FBXW7-mediated degradation within a positive transcriptional feedback loop [#8]. Loss of HEI10 abolishes chiasmata and causes sterility in both sexes [#1].\"\n,\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Identifying HEI10 as a chromosomal translocation partner gave the first hint of a disease association before any functional role was known.\",\n      \"evidence\": \"3' RACE cloning of an HMGIC-HEI10 fusion cDNA from uterine leiomyoma with radiation hybrid mapping\",\n      \"pmids\": [\"11223542\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Provides no functional mechanism for HEI10 itself\", \"Causal role of the fusion in tumorigenesis not established\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Discovery of a direct merlin (NF2) interaction placed HEI10 in a tumor-suppressor signalling context and mapped the binding interfaces.\",\n      \"evidence\": \"Co-immunoprecipitation, domain mapping, and co-localisation with constitutively open merlin in human cells\",\n      \"pmids\": [\"16532029\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of the interaction left unresolved\", \"Single lab without reciprocal in vivo validation\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Two independent lines of evidence established HEI10 both as an essential meiotic crossover factor and as a somatic suppressor of cell invasion acting through cyclin B/CDK1.\",\n      \"evidence\": \"ENU mutant cytological analysis of mouse spermatocytes/oocytes; siRNA knockdown with migration/invasion assays and Cdk1/cyclin B inhibitor rescue in human cells\",\n      \"pmids\": [\"17784788\", \"17297447\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct ubiquitin ligase activity not biochemically demonstrated\", \"Substrate of the proposed cyclin B ligase activity not identified\", \"Molecular link between merlin and the cyclin B axis untested\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Pachytene-stage chromosome loading plus a SUMO2 interaction screen reframed HEI10 as a crossover-maturation factor potentially acting as a SUMO ligase.\",\n      \"evidence\": \"Immunofluorescence localisation with specific antibody and yeast two-hybrid screen against sumoylation-consensus proteins\",\n      \"pmids\": [\"21779533\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"SUMO E3 ligase activity inferred but not reconstituted\", \"Y2H interactions not validated by reciprocal binding\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Rice work pinned HEI10 specifically to the class I crossover pathway and revealed its dynamic focus-to-line-to-focus localisation pattern.\",\n      \"evidence\": \"Map-based cloning and immunolocalisation on meiotic chromosomes in a hei10 null mutant\",\n      \"pmids\": [\"22792078\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism converting linear signal to discrete foci unknown\", \"Substrates ubiquitinated during maturation not identified\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Domain-specific mutagenesis dissected opposing roles of the RING and RXL domains in recombination-complex turnover and SUMO distribution.\",\n      \"evidence\": \"Null, RING-binding, and RXL domain mutant analysis with immunolocalisation and recombination nodule ultrastructure in Sordaria\",\n      \"pmids\": [\"24831702\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct catalytic targets of the RING domain not defined\", \"Biochemical basis of RXL-dependent SUMO modulation unresolved\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Genetic epistasis showed HEI10 dosage and SC diffusion drive a coarsening process that sets crossover number and spacing.\",\n      \"evidence\": \"HEI10 overexpression lines and HEI10-OE x zyp1 double-mutant crossover/interference analysis in Arabidopsis\",\n      \"pmids\": [\"36224180\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physical mechanism of coarsening not directly observed\", \"Conservation of dosage effect in animals untested\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Phase separation and substrate identification connected HEI10 condensation to its catalytic crossover function and to MYCN stability in cancer.\",\n      \"evidence\": \"LLPS assay, Ser70Phe mutagenesis, IP-MS, and ubiquitination assay in Arabidopsis; Co-IP, ubiquitination IP, ChIP, and luciferase reporter in neuroblastoma cells\",\n      \"pmids\": [\"38134200\", \"37461251\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether RPA1a ubiquitination is conserved beyond plants unknown\", \"Direct catalytic basis of MYCN protection (competition vs. enzymatic) not fully separated\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Condensation requirement, sex-specific RING dependence, and new interactors refined how HEI10 assembly and partners drive meiosis.\",\n      \"evidence\": \"Temperature-sensitive aggregation mutant (HEI10tfs2) and RING-truncation complementation in rice with Y2H against RPT4/SRFP1\",\n      \"pmids\": [\"38169508\", \"38180592\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Basis of sex-specific RING requirement unexplained\", \"RPT4/SRFP1 interactions not validated beyond Y2H\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identification of upstream regulators and a radiation-response substrate connected HEI10 recruitment and cyclin B1 control to physiological pathways.\",\n      \"evidence\": \"Heip1 knockout immunolocalisation and Co-IP in mouse; ubiquitination IP with rescue and ESR1/AdipoR1 transcriptional analysis in somatic cells\",\n      \"pmids\": [\"bio_10.1101_2025.08.25.672081\", \"39849382\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which HEIP1 nucleates HEI10/RNF212 loading unresolved\", \"HEIP1 finding is a preprint awaiting peer review\", \"Direct cyclin B1 ubiquitination by HEI10 versus indirect effect not fully separated\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"A crystal structure established the architectural basis linking higher-order self-assembly to E3 ligase catalysis.\",\n      \"evidence\": \"Crystal structure, structure-guided mutagenesis, and in vitro ubiquitin ligase assay of human HEI10 (preprint)\",\n      \"pmids\": [\"42146605\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether meiotic foci adopt the same tetrameric architecture in vivo untested\", \"Substrate-specifying determinants of the assembled ligase not defined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How HEI10's catalytic assembly, phase separation, and substrate choice are integrated to select discrete crossover sites and how these mechanisms translate to its somatic cyclin B/MYCN roles remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking in vitro tetramer assembly to in vivo foci\", \"Full substrate repertoire of the E3 ligase undefined\", \"Relationship between meiotic and oncogenic functions unestablished\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [0, 7]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 7, 8, 9]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [8, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [3, 11, 12]},\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [2, 3, 7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1474165\", \"supporting_discovery_ids\": [1, 2, 10]},\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [5, 9]},\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 7, 8]}\n    ],\n    \"complexes\": [\"synaptonemal complex central region\"],\n    \"partners\": [\"NF2\", \"MYCN\", \"FBXW7\", \"RPA1a\", \"HEIP1\", \"RNF212\", \"RPT4\", \"SRFP1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}