{"gene":"MAD2L1","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":1996,"finding":"Human MAD2 (hsMAD2) is a necessary component of the mitotic checkpoint in HeLa cells; antibody electroporation experiments demonstrated that blocking hsMAD2 abrogated mitotic arrest in response to spindle perturbation. hsMAD2 localizes to kinetochores after chromosome condensation but is absent from kinetochores at metaphase, consistent with a role in monitoring spindle-kinetochore attachment completion.","method":"Antibody electroporation into HeLa cells; immunofluorescence localization","journal":"Science","confidence":"High","confidence_rationale":"Tier 2 / Strong — functional antibody-interference experiment with defined mitotic phenotype plus direct localization data; foundational paper replicated extensively by subsequent work","pmids":["8824189"],"is_preprint":false},{"year":2001,"finding":"HsMAD2 associates with HsMAD1 in mammalian cells. During interphase, both HsMAD1 and HsMAD2 co-localize with nuclear pore complexes, as confirmed by co-labeling with nuclear pore complex antibodies and co-purification with enriched nuclear envelope fractions. Association with p55CDC (Cdc20) was not detected in this interphase context.","method":"Co-immunoprecipitation; co-immunofluorescence with nuclear pore complex markers; subcellular fractionation and co-purification","journal":"Journal of Cell Science","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-IP plus orthogonal co-localization and biochemical fractionation, independently consistent results across methods","pmids":["11181178"],"is_preprint":false},{"year":2002,"finding":"Two leucine zipper domains in hsMAD1 (amino acids 501–522 and 557–571) are required for its binding to hsMAD2. A coding polymorphism at codon 558 of hsMAD1 (Arg→His) reduces hsMAD1–hsMAD2 interaction and impairs mitotic arrest enforcement, directly linking the MAD1–MAD2 binding interface to spindle checkpoint function.","method":"Deletion/mutagenesis of hsMAD1 leucine zipper domains; co-immunoprecipitation; mitotic index / flow cytometry assays","journal":"The Journal of Biological Chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — mutagenesis defining binding domains combined with functional checkpoint assay, single lab but multiple orthogonal methods","pmids":["12042300"],"is_preprint":false},{"year":2004,"finding":"A ~0.5 kb fragment upstream of hsMAD2 functions as a strong promoter. In hepatocellular carcinoma cells, transcriptional silencing of hsMAD2 occurs via hypermethylation of this promoter, resulting in reduced hsMAD2 protein expression and defective mitotic checkpoint.","method":"Promoter cloning and reporter assay; bisulfite sequencing / methylation analysis; RT-PCR and western blot in HCC cell lines","journal":"Cancer Research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — promoter cloning with reporter validation plus methylation correlation with expression, single lab","pmids":["15574775"],"is_preprint":false},{"year":2010,"finding":"The ETV6/RUNX1 fusion oncogene and wild-type RUNX1 both bind RUNX1 sites in the MAD2L1 promoter, regulating its transcription; E/R expression downregulates MAD2L1 mRNA and protein, attenuates the mitotic checkpoint (reduced 4N DNA content and mitotic index after spindle toxin treatment), and promotes tetraploidy.","method":"Promoter-reporter assay; ChIP (RUNX1/E/R binding to MAD2L1 promoter); western blot; flow cytometry mitotic checkpoint assay; karyotyping","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — ChIP-validated promoter binding plus functional checkpoint readout plus mutant DNA-binding domain control, multiple orthogonal methods in single study","pmids":["20190817"],"is_preprint":false},{"year":2010,"finding":"A MAD2L1 missense variant Leu84Met impairs spindle checkpoint function: cells expressing MAD2L1-84Met show reduced 4N DNA content and lower mitotic index upon nocodazole treatment compared with cells expressing wild-type MAD2L1.","method":"Flow cytometry (4N DNA content); mitotic index assay after nocodazole treatment; transfection of wild-type vs. variant MAD2L1","journal":"Journal of Medical Genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — two orthogonal functional assays (flow cytometry + mitotic index) comparing wild-type vs. variant, single lab","pmids":["20516147"],"is_preprint":false},{"year":2020,"finding":"BRCA1 silencing leads to co-depletion of MAD2L1 at both mRNA and protein levels, consistent with MAD2L1 being a transcriptional target of BRCA1. Silencing MAD2L1 alone phenocopies BRCA1 loss by abrogating vinorelbine-induced cell-cycle arrest, BUBR1 kinetochore recruitment, and apoptosis, thereby conferring vinorelbine resistance.","method":"siRNA knockdown of BRCA1 and MAD2L1; RT-PCR and western blot; immunofluorescence for BUBR1 kinetochore localization; flow cytometry apoptosis/cell-cycle assay; ex vivo tumor explant apoptosis assay","journal":"Molecular Cancer Therapeutics","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (molecular, cell-biological, ex vivo) across cell lines and primary explants demonstrating the BRCA1→MAD2L1 transcriptional axis and its functional consequences","pmids":["33158996"],"is_preprint":false},{"year":2023,"finding":"TEAD4 binds to a recognition motif in the MAD2L1 promoter region and positively regulates MAD2L1 transcription. TEAD4 silencing suppresses CRC cell proliferation and migration, and this effect can be rescued by MAD2L1 overexpression, placing MAD2L1 downstream of TEAD4 in a growth-regulatory axis.","method":"Promoter binding assay (luciferase reporter with TEAD4 binding site); siRNA knockdown; overexpression rescue experiments; proliferation and migration assays","journal":"Cancer Gene Therapy","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — promoter reporter plus epistatic rescue experiment, single lab, two orthogonal methods","pmids":["36599972"],"is_preprint":false},{"year":2023,"finding":"MAD2L1 activates the TYK2/STAT3 signaling pathway (co-immunoprecipitation demonstrated physical interaction), and in turn STAT3 binds directly to the MAD2L1 promoter (ChIP assay) to induce its transcription, forming a positive-feedback loop (MAD2L1/TYK2/STAT3) that promotes B-ALL cell proliferation, migration, and invasion.","method":"Co-immunoprecipitation; western blot; luciferase reporter assay; chromatin immunoprecipitation (ChIP); siRNA knockdown; xenograft model","journal":"Journal of Cancer Research and Clinical Oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus ChIP plus functional rescue in single lab, multiple orthogonal methods but not independently replicated","pmids":["36781502"],"is_preprint":false},{"year":2025,"finding":"MAD2L1 physically interacts with NANOG (co-immunoprecipitation) and facilitates NANOG nuclear localization; MAD2L1 knockdown reduces NANOG expression and nuclear localization, whereas MAD2L1 overexpression increases resistance to carboplatin and stemness markers in lung cancer cells.","method":"Co-immunoprecipitation; fluorescence imaging of NANOG nuclear localization; gene knockdown/overexpression; cell viability and stemness assays; in vivo xenograft","journal":"Cellular Signalling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus imaging of localization change plus functional phenotype, single lab","pmids":["40233918"],"is_preprint":false},{"year":2025,"finding":"KAT2A-mediated lactylation of RCC2 at K124 enables RCC2 to recruit SERBP1, which stabilizes MAD2L1 mRNA; this post-translational modification cascade (high glucose → lactate → KAT2A → RCC2 lactylation → SERBP1 recruitment → MAD2L1 mRNA stabilization) upregulates MAD2L1 and promotes breast cancer cell proliferation.","method":"Mass spectrometry identification of lactylation site; mutagenesis of K124; RNA immunoprecipitation (RIP) for SERBP1-MAD2L1 mRNA interaction; mRNA stability assay; co-IP; small-molecule inhibitor blocking RCC2 lactylation; in vitro and in vivo proliferation assays","journal":"Advanced Science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple biochemical methods (MS, mutagenesis, RIP, mRNA stability) in single lab supporting the post-translational modification→mRNA stability axis","pmids":["40145796"],"is_preprint":false},{"year":2024,"finding":"KIFC1 interacts with FXR1 (an RNA-binding protein), and this interaction stabilizes MAD2L1 mRNA in an m6A-dependent manner; KIFC1 knockout reduces MAD2L1 mRNA stability and MAD2L1 protein levels, leading to cellular senescence in soft tissue sarcoma cells.","method":"Co-immunoprecipitation (KIFC1–FXR1); mRNA stability assay; m6A modification analysis; KIFC1 knockout (in vitro and PDX in vivo); senescence assays","journal":"Advanced Science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus mRNA stability plus m6A analysis plus in vivo PDX validation, single lab","pmids":["39387242"],"is_preprint":false},{"year":2025,"finding":"lncRNA SNHG8 interacts with the transcription factor E2F1 and recruits it to the MAD2L1 promoter, driving MAD2L1 transcription and promoting cardiac fibroblast proliferation/migration and cardiac fibrosis; SNHG8 knockout in mice reduces MAD2L1 protein levels and alleviates fibrosis.","method":"RNA immunoprecipitation; ChIP (E2F1 at MAD2L1 promoter); gain- and loss-of-function (siRNA/knockout); western blot; in vivo mouse cardiac fibrosis model","journal":"International Journal of Biological Macromolecules","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP demonstrating E2F1 recruitment to MAD2L1 promoter plus in vivo knockout validation, single lab","pmids":["41109373"],"is_preprint":false},{"year":2017,"finding":"MAD2L1 (mitotic arrest deficient 2-like 1) is a component of the spindle assembly checkpoint (SAC); oxidative stress (H2O2) activates the SAC in mouse zygotes as shown by increased MAD2L1 immunofluorescence signal, resulting in a prometaphase/metaphase delay during first cleavage.","method":"Immunofluorescence staining for MAD2L1 and TTK in H2O2-treated mouse zygotes; time-course monitoring of H3S10P as prometaphase/metaphase marker","journal":"Oxidative Medicine and Cellular Longevity","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single immunofluorescence method in a mouse zygote model, no functional manipulation of MAD2L1 itself","pmids":["29147457"],"is_preprint":false},{"year":2042,"finding":"MAD2L1 knockdown in hepatoblastoma cells inhibits proliferation, migration, and invasion, and MAD2L1 promotes cell cycle progression through regulation of E2F transcription factor activity (western blot/cell cycle analysis).","method":"siRNA knockdown; CCK-8 proliferation assay; migration/invasion assays; western blot for E2F pathway components; cell cycle analysis","journal":"Frontiers in Oncology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, KD phenotype with partial pathway placement (E2F regulation) but limited mechanistic depth from abstract","pmids":["40231267"],"is_preprint":false}],"current_model":"MAD2L1 (hsMAD2) is a core spindle assembly checkpoint (SAC) component that localizes to unattached kinetochores from prometaphase until all chromosomes achieve proper microtubule attachment; it forms a complex with MAD1 (via MAD1 leucine zipper domains) and during interphase associates with nuclear pore complexes, and its activity is required to prevent premature anaphase onset. Its transcription is regulated by multiple upstream inputs including BRCA1, ETV6/RUNX1, TEAD4, and the E2F1/SNHG8 axis, while its mRNA stability is controlled post-transcriptionally by FXR1/KIFC1 (m6A-dependent) and by the RCC2 lactylation–SERBP1 axis under high-glucose conditions; beyond its canonical mitotic role, MAD2L1 has been shown to interact with NANOG to facilitate its nuclear localization (contributing to chemoresistance) and to activate TYK2/STAT3 signaling in a positive feedback loop."},"narrative":{"mechanistic_narrative":"MAD2L1 (hsMAD2) is a core component of the mitotic spindle assembly checkpoint (SAC) that monitors the completion of microtubule–kinetochore attachment to prevent premature anaphase onset [PMID:8824189]. It localizes to kinetochores after chromosome condensation and disappears from them by metaphase, and antibody-mediated interference with hsMAD2 abolishes mitotic arrest in response to spindle perturbation, establishing it as functionally required for checkpoint enforcement [PMID:8824189]. Checkpoint activity depends on its association with MAD1: two leucine zipper domains in hsMAD1 (residues 501–522 and 557–571) mediate binding, and a codon-558 Arg→His polymorphism that weakens this interface impairs mitotic arrest [PMID:12042300]. During interphase, both proteins co-localize with nuclear pore complexes rather than with Cdc20 (p55CDC) [PMID:11181178]. Loss of MAD2L1 function—through promoter hypermethylation in hepatocellular carcinoma [PMID:15574775] or a Leu84Met missense variant [PMID:20516147]—produces a defective checkpoint, reduced 4N DNA content, and tetraploidy. MAD2L1 transcription is controlled by multiple upstream inputs, including RUNX1 and the ETV6/RUNX1 fusion acting on RUNX1 sites in its promoter [PMID:20190817], BRCA1 [PMID:33158996], and TEAD4 [PMID:36599972], while its abundance is also set post-transcriptionally by mRNA-stabilizing axes including KIFC1/FXR1 (m6A-dependent) [PMID:39387242] and KAT2A-driven RCC2 lactylation–SERBP1 under high glucose [PMID:40145796]. Beyond mitosis, MAD2L1 participates in oncogenic circuits: it engages a TYK2/STAT3 positive-feedback loop in B-ALL [PMID:36781502] and binds NANOG to promote its nuclear localization and chemoresistance in lung cancer [PMID:40233918].","teleology":[{"year":1996,"claim":"Established that human MAD2 is functionally required for the mitotic checkpoint, moving it from a candidate to a defined SAC effector whose loss permits anaphase despite spindle damage.","evidence":"Antibody electroporation into HeLa cells with mitotic-arrest readout plus kinetochore immunofluorescence","pmids":["8824189"],"confidence":"High","gaps":["Molecular partners mediating checkpoint signaling not yet defined","Does not address how kinetochore attachment status is sensed"]},{"year":2001,"claim":"Identified MAD1 as the partner of MAD2 and revealed an unexpected interphase localization at nuclear pore complexes, distinguishing the MAD1–MAD2 complex from a Cdc20-bound state.","evidence":"Reciprocal co-IP, co-immunofluorescence with NPC markers, and nuclear envelope fractionation in mammalian cells","pmids":["11181178"],"confidence":"High","gaps":["Functional role of NPC association during interphase not established","Does not define the structural basis of MAD1–MAD2 binding"]},{"year":2002,"claim":"Mapped the MAD1–MAD2 binding interface to two MAD1 leucine zipper domains and linked it directly to checkpoint function via a natural polymorphism that weakens binding.","evidence":"Deletion/mutagenesis of MAD1 leucine zippers, co-IP, and mitotic index/flow cytometry assays","pmids":["12042300"],"confidence":"High","gaps":["Structural geometry of the interaction not resolved","Single-lab functional readout"]},{"year":2010,"claim":"Demonstrated transcriptional control of MAD2L1 by RUNX1 and its leukemic fusion ETV6/RUNX1, connecting checkpoint gene dosage to aneuploidy and tetraploidy in leukemia.","evidence":"ChIP-validated promoter binding, reporter assays, checkpoint flow cytometry, and karyotyping","pmids":["20190817"],"confidence":"High","gaps":["Whether downregulation drives tumorigenesis in vivo not shown","Other promoter regulators not excluded"]},{"year":2010,"claim":"Showed that a MAD2L1 coding variant (Leu84Met) impairs checkpoint enforcement, providing genetic evidence that MAD2L1 sequence integrity is required for SAC function.","evidence":"Flow cytometry 4N DNA content and mitotic index after nocodazole comparing wild-type vs variant transfection","pmids":["20516147"],"confidence":"Medium","gaps":["Mechanism by which Leu84Met perturbs MAD2 not defined","Single-lab functional assay"]},{"year":2004,"claim":"Identified epigenetic silencing of MAD2L1 by promoter hypermethylation as a route to checkpoint defects in hepatocellular carcinoma.","evidence":"Promoter cloning/reporter assay, bisulfite sequencing, RT-PCR and western blot in HCC lines","pmids":["15574775"],"confidence":"Medium","gaps":["Causal demethylation rescue not shown","Single tumor type"]},{"year":2020,"claim":"Placed MAD2L1 downstream of BRCA1 transcriptionally and showed its loss phenocopies BRCA1 deficiency, linking it to BUBR1 kinetochore recruitment and drug-induced apoptosis.","evidence":"siRNA knockdown, RT-PCR/western, BUBR1 immunofluorescence, apoptosis/cell-cycle flow cytometry, and ex vivo explants","pmids":["33158996"],"confidence":"High","gaps":["Direct BRCA1 promoter occupancy at MAD2L1 not demonstrated","Mechanism of BUBR1 dependence not detailed"]},{"year":2023,"claim":"Established TEAD4 as a positive transcriptional regulator of MAD2L1 driving colorectal cancer growth, validated by epistatic rescue.","evidence":"Luciferase reporter with TEAD4 binding site, siRNA knockdown, and MAD2L1 overexpression rescue of proliferation/migration","pmids":["36599972"],"confidence":"Medium","gaps":["Direct ChIP occupancy not shown","Single lab"]},{"year":2023,"claim":"Uncovered a non-mitotic oncogenic role: MAD2L1 activates TYK2/STAT3 signaling while STAT3 transcriptionally feeds back on MAD2L1, forming a self-amplifying loop in B-ALL.","evidence":"Co-IP, ChIP, luciferase reporter, siRNA knockdown, and xenograft","pmids":["36781502"],"confidence":"Medium","gaps":["Direct vs indirect nature of MAD2L1–TYK2 interaction unclear","Not independently replicated"]},{"year":2024,"claim":"Defined a post-transcriptional axis in which KIFC1–FXR1 stabilizes MAD2L1 mRNA in an m6A-dependent manner, with loss driving senescence in sarcoma.","evidence":"Co-IP, mRNA stability assays, m6A analysis, and KIFC1 knockout in vitro and in PDX","pmids":["39387242"],"confidence":"Medium","gaps":["The m6A reader/writer at MAD2L1 transcripts not identified","Single lab"]},{"year":2025,"claim":"Showed that high-glucose-driven RCC2 lactylation recruits SERBP1 to stabilize MAD2L1 mRNA, coupling metabolic state to MAD2L1 levels in breast cancer.","evidence":"Mass spectrometry of lactylation site, K124 mutagenesis, RIP, mRNA stability, co-IP, inhibitor, and in vivo proliferation","pmids":["40145796"],"confidence":"Medium","gaps":["Direct SERBP1–MAD2L1 mRNA element not mapped","Single lab"]},{"year":2025,"claim":"Identified MAD2L1 as a NANOG partner promoting NANOG nuclear localization, stemness, and carboplatin resistance in lung cancer.","evidence":"Co-IP, NANOG localization imaging, knockdown/overexpression, viability/stemness assays, and xenograft","pmids":["40233918"],"confidence":"Medium","gaps":["Structural basis of MAD2L1–NANOG binding unknown","Relationship to mitotic function not addressed"]},{"year":2025,"claim":"Extended MAD2L1 transcriptional control to a non-cancer context, with lncRNA SNHG8 recruiting E2F1 to the MAD2L1 promoter to drive cardiac fibrosis.","evidence":"RIP, ChIP of E2F1 at promoter, gain/loss-of-function, and in vivo SNHG8 knockout cardiac fibrosis model","pmids":["41109373"],"confidence":"Medium","gaps":["Whether E2F1 directly binds MAD2L1 promoter independent of SNHG8 unclear","Single lab"]},{"year":null,"claim":"How MAD2L1's canonical SAC function mechanistically intersects with its newly described oncogenic interactions (NANOG, TYK2/STAT3) and the multiple convergent transcriptional/post-transcriptional control inputs remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking mitotic and non-mitotic roles","Structural details of MAD2L1 complexes in human cells not resolved in corpus"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,2]},{"term_id":"GO:0060089","term_label":"molecular transducer activity","supporting_discovery_ids":[0]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[1]},{"term_id":"GO:0005635","term_label":"nuclear envelope","supporting_discovery_ids":[1]}],"pathway":[{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[0,2,4]}],"complexes":["MAD1-MAD2 complex"],"partners":["MAD1L1","NANOG","TYK2","STAT3"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q13257","full_name":"Mitotic spindle assembly checkpoint protein MAD2A","aliases":["Mitotic arrest deficient 2-like protein 1","MAD2-like protein 1"],"length_aa":205,"mass_kda":23.5,"function":"Component of the spindle-assembly checkpoint that prevents the onset of anaphase until all chromosomes are properly aligned at the metaphase plate (PubMed:15024386, PubMed:29162720). In the closed conformation (C-MAD2) forms a heterotetrameric complex with MAD1L1 at unattached kinetochores during prometaphase, the complex recruits open conformation molecules of MAD2L1 (O-MAD2) and then promotes the conversion of O-MAD2 to C-MAD2 (PubMed:29162720). Required for the execution of the mitotic checkpoint which monitors the process of kinetochore-spindle attachment and inhibits the activity of the anaphase promoting complex by sequestering CDC20 until all chromosomes are aligned at the metaphase plate (PubMed:10700282, PubMed:11804586, PubMed:15024386)","subcellular_location":"Nucleus; Chromosome, centromere, kinetochore; Cytoplasm; Cytoplasm, cytoskeleton, spindle pole","url":"https://www.uniprot.org/uniprotkb/Q13257/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/MAD2L1","classification":"Common Essential","n_dependent_lines":1185,"n_total_lines":1208,"dependency_fraction":0.9809602649006622},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"ANAPC4","stoichiometry":0.2},{"gene":"ARFGAP2","stoichiometry":0.2},{"gene":"CAPZB","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/MAD2L1","total_profiled":1310},"omim":[{"mim_id":"621142","title":"CHROMOSOME 15 OPEN READING FRAME 39; C15ORF39","url":"https://www.omim.org/entry/621142"},{"mim_id":"618796","title":"SAC3 DOMAIN-CONTAINING PROTEIN 1; SAC3D1","url":"https://www.omim.org/entry/618796"},{"mim_id":"618136","title":"MAD2L1-BINDING PROTEIN; MAD2L1BP","url":"https://www.omim.org/entry/618136"},{"mim_id":"616401","title":"SPINDLE APPARATUS COILED-COIL PROTEIN 1; SPDL1","url":"https://www.omim.org/entry/616401"},{"mim_id":"615890","title":"DYNEIN, CYTOPLASMIC 1, LIGHT INTERMEDIATE CHAIN 1; DYNC1LI1","url":"https://www.omim.org/entry/615890"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"bone marrow","ntpm":5.5},{"tissue":"lymphoid tissue","ntpm":5.3}],"url":"https://www.proteinatlas.org/search/MAD2L1"},"hgnc":{"alias_symbol":["MAD2","HSMAD2"],"prev_symbol":[]},"alphafold":{"accession":"Q13257","domains":[{"cath_id":"3.30.900.10","chopping":"12-198","consensus_level":"high","plddt":95.8148,"start":12,"end":198}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13257","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q13257-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q13257-F1-predicted_aligned_error_v6.png","plddt_mean":93.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MAD2L1","jax_strain_url":"https://www.jax.org/strain/search?query=MAD2L1"},"sequence":{"accession":"Q13257","fasta_url":"https://rest.uniprot.org/uniprotkb/Q13257.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q13257/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13257"}},"corpus_meta":[{"pmid":"8824189","id":"PMC_8824189","title":"Identification of a human mitotic checkpoint gene: hsMAD2.","date":"1996","source":"Science (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/8824189","citation_count":526,"is_preprint":false},{"pmid":"11181178","id":"PMC_11181178","title":"Mitotic checkpoint proteins HsMAD1 and HsMAD2 are associated with nuclear pore complexes in interphase.","date":"2001","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/11181178","citation_count":162,"is_preprint":false},{"pmid":"10439037","id":"PMC_10439037","title":"Identification of frequent impairment of the mitotic checkpoint and molecular analysis of the mitotic checkpoint genes, hsMAD2 and p55CDC, in human lung cancers.","date":"1999","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/10439037","citation_count":105,"is_preprint":false},{"pmid":"11400114","id":"PMC_11400114","title":"Molecular analyses of the mitotic checkpoint components hsMAD2, hBUB1 and hBUB3 in human cancer.","date":"2001","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/11400114","citation_count":86,"is_preprint":false},{"pmid":"10543255","id":"PMC_10543255","title":"Mutational inactivation of mitotic checkpoint genes, hsMAD2 and hBUB1, is rare in sporadic digestive tract cancers.","date":"1999","source":"Japanese journal of cancer research : Gann","url":"https://pubmed.ncbi.nlm.nih.gov/10543255","citation_count":84,"is_preprint":false},{"pmid":"11066082","id":"PMC_11066082","title":"Expression and mutational analyses of the human MAD2L1 gene in breast cancer cells.","date":"2000","source":"Genes, chromosomes & cancer","url":"https://pubmed.ncbi.nlm.nih.gov/11066082","citation_count":73,"is_preprint":false},{"pmid":"28609841","id":"PMC_28609841","title":"MiR-200c-5p suppresses proliferation and metastasis of human hepatocellular carcinoma (HCC) via suppressing MAD2L1.","date":"2017","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/28609841","citation_count":73,"is_preprint":false},{"pmid":"11572763","id":"PMC_11572763","title":"Mitotic checkpoint protein hsMAD2 as a marker predicting liver metastasis of human gastric cancers.","date":"2001","source":"Japanese journal of cancer research : Gann","url":"https://pubmed.ncbi.nlm.nih.gov/11572763","citation_count":52,"is_preprint":false},{"pmid":"31908496","id":"PMC_31908496","title":"miR-30a-3p Targets MAD2L1 and Regulates Proliferation of Gastric Cancer Cells.","date":"2019","source":"OncoTargets and therapy","url":"https://pubmed.ncbi.nlm.nih.gov/31908496","citation_count":51,"is_preprint":false},{"pmid":"28318489","id":"PMC_28318489","title":"Deletion of the MAD2L1 spindle assembly checkpoint gene is tolerated in mouse models of acute T-cell lymphoma and hepatocellular 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A polymorphic change in an hsMAD1 leucine zipper affects MAD1-MAD2 interaction and spindle checkpoint function.","date":"2002","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12042300","citation_count":39,"is_preprint":false},{"pmid":"15574775","id":"PMC_15574775","title":"Transcriptional abnormality of the hsMAD2 mitotic checkpoint gene is a potential link to hepatocellular carcinogenesis.","date":"2004","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/15574775","citation_count":38,"is_preprint":false},{"pmid":"18691855","id":"PMC_18691855","title":"Mitotic checkpoint genes, hsMAD2 and BubR1, in oesophageal squamous cancer cells and their association with 5-fluorouracil and cisplatin-based radiochemotherapy.","date":"2008","source":"Clinical oncology (Royal College of Radiologists (Great 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Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/39387242","citation_count":6,"is_preprint":false},{"pmid":"40233918","id":"PMC_40233918","title":"MAD2L1-mediated NANOG nuclear translocation: A critical factor in lung cancer chemoresistance.","date":"2025","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/40233918","citation_count":4,"is_preprint":false},{"pmid":"34728029","id":"PMC_34728029","title":"[Dysregulation of MAD2L1/CAMK2A/PTTG1 Gene Cluster Maintains the Stemness Characteristics of Uterine Corpus Endometrial Carcinoma].","date":"2021","source":"Zhongguo yi xue ke xue yuan xue bao. 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reports","url":"https://pubmed.ncbi.nlm.nih.gov/41378098","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":27452,"output_tokens":3954,"usd":0.070833,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11876,"output_tokens":3979,"usd":0.079427,"stage2_stop_reason":"end_turn"},"total_usd":0.15026,"stage1_batch_id":"msgbatch_01BbTCMyrRPyhtEq6b1MdwCN","stage2_batch_id":"msgbatch_011dEed5bbxYvTAaQWKJevxu","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1996,\n      \"finding\": \"Human MAD2 (hsMAD2) is a necessary component of the mitotic checkpoint in HeLa cells; antibody electroporation experiments demonstrated that blocking hsMAD2 abrogated mitotic arrest in response to spindle perturbation. hsMAD2 localizes to kinetochores after chromosome condensation but is absent from kinetochores at metaphase, consistent with a role in monitoring spindle-kinetochore attachment completion.\",\n      \"method\": \"Antibody electroporation into HeLa cells; immunofluorescence localization\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — functional antibody-interference experiment with defined mitotic phenotype plus direct localization data; foundational paper replicated extensively by subsequent work\",\n      \"pmids\": [\"8824189\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"HsMAD2 associates with HsMAD1 in mammalian cells. During interphase, both HsMAD1 and HsMAD2 co-localize with nuclear pore complexes, as confirmed by co-labeling with nuclear pore complex antibodies and co-purification with enriched nuclear envelope fractions. Association with p55CDC (Cdc20) was not detected in this interphase context.\",\n      \"method\": \"Co-immunoprecipitation; co-immunofluorescence with nuclear pore complex markers; subcellular fractionation and co-purification\",\n      \"journal\": \"Journal of Cell Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-IP plus orthogonal co-localization and biochemical fractionation, independently consistent results across methods\",\n      \"pmids\": [\"11181178\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Two leucine zipper domains in hsMAD1 (amino acids 501–522 and 557–571) are required for its binding to hsMAD2. A coding polymorphism at codon 558 of hsMAD1 (Arg→His) reduces hsMAD1–hsMAD2 interaction and impairs mitotic arrest enforcement, directly linking the MAD1–MAD2 binding interface to spindle checkpoint function.\",\n      \"method\": \"Deletion/mutagenesis of hsMAD1 leucine zipper domains; co-immunoprecipitation; mitotic index / flow cytometry assays\",\n      \"journal\": \"The Journal of Biological Chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — mutagenesis defining binding domains combined with functional checkpoint assay, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"12042300\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"A ~0.5 kb fragment upstream of hsMAD2 functions as a strong promoter. In hepatocellular carcinoma cells, transcriptional silencing of hsMAD2 occurs via hypermethylation of this promoter, resulting in reduced hsMAD2 protein expression and defective mitotic checkpoint.\",\n      \"method\": \"Promoter cloning and reporter assay; bisulfite sequencing / methylation analysis; RT-PCR and western blot in HCC cell lines\",\n      \"journal\": \"Cancer Research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — promoter cloning with reporter validation plus methylation correlation with expression, single lab\",\n      \"pmids\": [\"15574775\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The ETV6/RUNX1 fusion oncogene and wild-type RUNX1 both bind RUNX1 sites in the MAD2L1 promoter, regulating its transcription; E/R expression downregulates MAD2L1 mRNA and protein, attenuates the mitotic checkpoint (reduced 4N DNA content and mitotic index after spindle toxin treatment), and promotes tetraploidy.\",\n      \"method\": \"Promoter-reporter assay; ChIP (RUNX1/E/R binding to MAD2L1 promoter); western blot; flow cytometry mitotic checkpoint assay; karyotyping\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — ChIP-validated promoter binding plus functional checkpoint readout plus mutant DNA-binding domain control, multiple orthogonal methods in single study\",\n      \"pmids\": [\"20190817\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"A MAD2L1 missense variant Leu84Met impairs spindle checkpoint function: cells expressing MAD2L1-84Met show reduced 4N DNA content and lower mitotic index upon nocodazole treatment compared with cells expressing wild-type MAD2L1.\",\n      \"method\": \"Flow cytometry (4N DNA content); mitotic index assay after nocodazole treatment; transfection of wild-type vs. variant MAD2L1\",\n      \"journal\": \"Journal of Medical Genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — two orthogonal functional assays (flow cytometry + mitotic index) comparing wild-type vs. variant, single lab\",\n      \"pmids\": [\"20516147\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"BRCA1 silencing leads to co-depletion of MAD2L1 at both mRNA and protein levels, consistent with MAD2L1 being a transcriptional target of BRCA1. Silencing MAD2L1 alone phenocopies BRCA1 loss by abrogating vinorelbine-induced cell-cycle arrest, BUBR1 kinetochore recruitment, and apoptosis, thereby conferring vinorelbine resistance.\",\n      \"method\": \"siRNA knockdown of BRCA1 and MAD2L1; RT-PCR and western blot; immunofluorescence for BUBR1 kinetochore localization; flow cytometry apoptosis/cell-cycle assay; ex vivo tumor explant apoptosis assay\",\n      \"journal\": \"Molecular Cancer Therapeutics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (molecular, cell-biological, ex vivo) across cell lines and primary explants demonstrating the BRCA1→MAD2L1 transcriptional axis and its functional consequences\",\n      \"pmids\": [\"33158996\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TEAD4 binds to a recognition motif in the MAD2L1 promoter region and positively regulates MAD2L1 transcription. TEAD4 silencing suppresses CRC cell proliferation and migration, and this effect can be rescued by MAD2L1 overexpression, placing MAD2L1 downstream of TEAD4 in a growth-regulatory axis.\",\n      \"method\": \"Promoter binding assay (luciferase reporter with TEAD4 binding site); siRNA knockdown; overexpression rescue experiments; proliferation and migration assays\",\n      \"journal\": \"Cancer Gene Therapy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — promoter reporter plus epistatic rescue experiment, single lab, two orthogonal methods\",\n      \"pmids\": [\"36599972\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MAD2L1 activates the TYK2/STAT3 signaling pathway (co-immunoprecipitation demonstrated physical interaction), and in turn STAT3 binds directly to the MAD2L1 promoter (ChIP assay) to induce its transcription, forming a positive-feedback loop (MAD2L1/TYK2/STAT3) that promotes B-ALL cell proliferation, migration, and invasion.\",\n      \"method\": \"Co-immunoprecipitation; western blot; luciferase reporter assay; chromatin immunoprecipitation (ChIP); siRNA knockdown; xenograft model\",\n      \"journal\": \"Journal of Cancer Research and Clinical Oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus ChIP plus functional rescue in single lab, multiple orthogonal methods but not independently replicated\",\n      \"pmids\": [\"36781502\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MAD2L1 physically interacts with NANOG (co-immunoprecipitation) and facilitates NANOG nuclear localization; MAD2L1 knockdown reduces NANOG expression and nuclear localization, whereas MAD2L1 overexpression increases resistance to carboplatin and stemness markers in lung cancer cells.\",\n      \"method\": \"Co-immunoprecipitation; fluorescence imaging of NANOG nuclear localization; gene knockdown/overexpression; cell viability and stemness assays; in vivo xenograft\",\n      \"journal\": \"Cellular Signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus imaging of localization change plus functional phenotype, single lab\",\n      \"pmids\": [\"40233918\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"KAT2A-mediated lactylation of RCC2 at K124 enables RCC2 to recruit SERBP1, which stabilizes MAD2L1 mRNA; this post-translational modification cascade (high glucose → lactate → KAT2A → RCC2 lactylation → SERBP1 recruitment → MAD2L1 mRNA stabilization) upregulates MAD2L1 and promotes breast cancer cell proliferation.\",\n      \"method\": \"Mass spectrometry identification of lactylation site; mutagenesis of K124; RNA immunoprecipitation (RIP) for SERBP1-MAD2L1 mRNA interaction; mRNA stability assay; co-IP; small-molecule inhibitor blocking RCC2 lactylation; in vitro and in vivo proliferation assays\",\n      \"journal\": \"Advanced Science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple biochemical methods (MS, mutagenesis, RIP, mRNA stability) in single lab supporting the post-translational modification→mRNA stability axis\",\n      \"pmids\": [\"40145796\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"KIFC1 interacts with FXR1 (an RNA-binding protein), and this interaction stabilizes MAD2L1 mRNA in an m6A-dependent manner; KIFC1 knockout reduces MAD2L1 mRNA stability and MAD2L1 protein levels, leading to cellular senescence in soft tissue sarcoma cells.\",\n      \"method\": \"Co-immunoprecipitation (KIFC1–FXR1); mRNA stability assay; m6A modification analysis; KIFC1 knockout (in vitro and PDX in vivo); senescence assays\",\n      \"journal\": \"Advanced Science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus mRNA stability plus m6A analysis plus in vivo PDX validation, single lab\",\n      \"pmids\": [\"39387242\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"lncRNA SNHG8 interacts with the transcription factor E2F1 and recruits it to the MAD2L1 promoter, driving MAD2L1 transcription and promoting cardiac fibroblast proliferation/migration and cardiac fibrosis; SNHG8 knockout in mice reduces MAD2L1 protein levels and alleviates fibrosis.\",\n      \"method\": \"RNA immunoprecipitation; ChIP (E2F1 at MAD2L1 promoter); gain- and loss-of-function (siRNA/knockout); western blot; in vivo mouse cardiac fibrosis model\",\n      \"journal\": \"International Journal of Biological Macromolecules\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP demonstrating E2F1 recruitment to MAD2L1 promoter plus in vivo knockout validation, single lab\",\n      \"pmids\": [\"41109373\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"MAD2L1 (mitotic arrest deficient 2-like 1) is a component of the spindle assembly checkpoint (SAC); oxidative stress (H2O2) activates the SAC in mouse zygotes as shown by increased MAD2L1 immunofluorescence signal, resulting in a prometaphase/metaphase delay during first cleavage.\",\n      \"method\": \"Immunofluorescence staining for MAD2L1 and TTK in H2O2-treated mouse zygotes; time-course monitoring of H3S10P as prometaphase/metaphase marker\",\n      \"journal\": \"Oxidative Medicine and Cellular Longevity\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single immunofluorescence method in a mouse zygote model, no functional manipulation of MAD2L1 itself\",\n      \"pmids\": [\"29147457\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2042,\n      \"finding\": \"MAD2L1 knockdown in hepatoblastoma cells inhibits proliferation, migration, and invasion, and MAD2L1 promotes cell cycle progression through regulation of E2F transcription factor activity (western blot/cell cycle analysis).\",\n      \"method\": \"siRNA knockdown; CCK-8 proliferation assay; migration/invasion assays; western blot for E2F pathway components; cell cycle analysis\",\n      \"journal\": \"Frontiers in Oncology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, KD phenotype with partial pathway placement (E2F regulation) but limited mechanistic depth from abstract\",\n      \"pmids\": [\"40231267\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MAD2L1 (hsMAD2) is a core spindle assembly checkpoint (SAC) component that localizes to unattached kinetochores from prometaphase until all chromosomes achieve proper microtubule attachment; it forms a complex with MAD1 (via MAD1 leucine zipper domains) and during interphase associates with nuclear pore complexes, and its activity is required to prevent premature anaphase onset. Its transcription is regulated by multiple upstream inputs including BRCA1, ETV6/RUNX1, TEAD4, and the E2F1/SNHG8 axis, while its mRNA stability is controlled post-transcriptionally by FXR1/KIFC1 (m6A-dependent) and by the RCC2 lactylation–SERBP1 axis under high-glucose conditions; beyond its canonical mitotic role, MAD2L1 has been shown to interact with NANOG to facilitate its nuclear localization (contributing to chemoresistance) and to activate TYK2/STAT3 signaling in a positive feedback loop.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"MAD2L1 (hsMAD2) is a core component of the mitotic spindle assembly checkpoint (SAC) that monitors the completion of microtubule–kinetochore attachment to prevent premature anaphase onset [#0]. It localizes to kinetochores after chromosome condensation and disappears from them by metaphase, and antibody-mediated interference with hsMAD2 abolishes mitotic arrest in response to spindle perturbation, establishing it as functionally required for checkpoint enforcement [#0]. Checkpoint activity depends on its association with MAD1: two leucine zipper domains in hsMAD1 (residues 501–522 and 557–571) mediate binding, and a codon-558 Arg→His polymorphism that weakens this interface impairs mitotic arrest [#2]. During interphase, both proteins co-localize with nuclear pore complexes rather than with Cdc20 (p55CDC) [#1]. Loss of MAD2L1 function—through promoter hypermethylation in hepatocellular carcinoma [#3] or a Leu84Met missense variant [#5]—produces a defective checkpoint, reduced 4N DNA content, and tetraploidy. MAD2L1 transcription is controlled by multiple upstream inputs, including RUNX1 and the ETV6/RUNX1 fusion acting on RUNX1 sites in its promoter [#4], BRCA1 [#6], and TEAD4 [#7], while its abundance is also set post-transcriptionally by mRNA-stabilizing axes including KIFC1/FXR1 (m6A-dependent) [#11] and KAT2A-driven RCC2 lactylation–SERBP1 under high glucose [#10]. Beyond mitosis, MAD2L1 participates in oncogenic circuits: it engages a TYK2/STAT3 positive-feedback loop in B-ALL [#8] and binds NANOG to promote its nuclear localization and chemoresistance in lung cancer [#9].\",\n  \"teleology\": [\n    {\n      \"year\": 1996,\n      \"claim\": \"Established that human MAD2 is functionally required for the mitotic checkpoint, moving it from a candidate to a defined SAC effector whose loss permits anaphase despite spindle damage.\",\n      \"evidence\": \"Antibody electroporation into HeLa cells with mitotic-arrest readout plus kinetochore immunofluorescence\",\n      \"pmids\": [\"8824189\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular partners mediating checkpoint signaling not yet defined\", \"Does not address how kinetochore attachment status is sensed\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Identified MAD1 as the partner of MAD2 and revealed an unexpected interphase localization at nuclear pore complexes, distinguishing the MAD1–MAD2 complex from a Cdc20-bound state.\",\n      \"evidence\": \"Reciprocal co-IP, co-immunofluorescence with NPC markers, and nuclear envelope fractionation in mammalian cells\",\n      \"pmids\": [\"11181178\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional role of NPC association during interphase not established\", \"Does not define the structural basis of MAD1–MAD2 binding\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Mapped the MAD1–MAD2 binding interface to two MAD1 leucine zipper domains and linked it directly to checkpoint function via a natural polymorphism that weakens binding.\",\n      \"evidence\": \"Deletion/mutagenesis of MAD1 leucine zippers, co-IP, and mitotic index/flow cytometry assays\",\n      \"pmids\": [\"12042300\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural geometry of the interaction not resolved\", \"Single-lab functional readout\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Demonstrated transcriptional control of MAD2L1 by RUNX1 and its leukemic fusion ETV6/RUNX1, connecting checkpoint gene dosage to aneuploidy and tetraploidy in leukemia.\",\n      \"evidence\": \"ChIP-validated promoter binding, reporter assays, checkpoint flow cytometry, and karyotyping\",\n      \"pmids\": [\"20190817\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether downregulation drives tumorigenesis in vivo not shown\", \"Other promoter regulators not excluded\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Showed that a MAD2L1 coding variant (Leu84Met) impairs checkpoint enforcement, providing genetic evidence that MAD2L1 sequence integrity is required for SAC function.\",\n      \"evidence\": \"Flow cytometry 4N DNA content and mitotic index after nocodazole comparing wild-type vs variant transfection\",\n      \"pmids\": [\"20516147\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which Leu84Met perturbs MAD2 not defined\", \"Single-lab functional assay\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Identified epigenetic silencing of MAD2L1 by promoter hypermethylation as a route to checkpoint defects in hepatocellular carcinoma.\",\n      \"evidence\": \"Promoter cloning/reporter assay, bisulfite sequencing, RT-PCR and western blot in HCC lines\",\n      \"pmids\": [\"15574775\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Causal demethylation rescue not shown\", \"Single tumor type\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Placed MAD2L1 downstream of BRCA1 transcriptionally and showed its loss phenocopies BRCA1 deficiency, linking it to BUBR1 kinetochore recruitment and drug-induced apoptosis.\",\n      \"evidence\": \"siRNA knockdown, RT-PCR/western, BUBR1 immunofluorescence, apoptosis/cell-cycle flow cytometry, and ex vivo explants\",\n      \"pmids\": [\"33158996\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct BRCA1 promoter occupancy at MAD2L1 not demonstrated\", \"Mechanism of BUBR1 dependence not detailed\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Established TEAD4 as a positive transcriptional regulator of MAD2L1 driving colorectal cancer growth, validated by epistatic rescue.\",\n      \"evidence\": \"Luciferase reporter with TEAD4 binding site, siRNA knockdown, and MAD2L1 overexpression rescue of proliferation/migration\",\n      \"pmids\": [\"36599972\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct ChIP occupancy not shown\", \"Single lab\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Uncovered a non-mitotic oncogenic role: MAD2L1 activates TYK2/STAT3 signaling while STAT3 transcriptionally feeds back on MAD2L1, forming a self-amplifying loop in B-ALL.\",\n      \"evidence\": \"Co-IP, ChIP, luciferase reporter, siRNA knockdown, and xenograft\",\n      \"pmids\": [\"36781502\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct vs indirect nature of MAD2L1–TYK2 interaction unclear\", \"Not independently replicated\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined a post-transcriptional axis in which KIFC1–FXR1 stabilizes MAD2L1 mRNA in an m6A-dependent manner, with loss driving senescence in sarcoma.\",\n      \"evidence\": \"Co-IP, mRNA stability assays, m6A analysis, and KIFC1 knockout in vitro and in PDX\",\n      \"pmids\": [\"39387242\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"The m6A reader/writer at MAD2L1 transcripts not identified\", \"Single lab\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Showed that high-glucose-driven RCC2 lactylation recruits SERBP1 to stabilize MAD2L1 mRNA, coupling metabolic state to MAD2L1 levels in breast cancer.\",\n      \"evidence\": \"Mass spectrometry of lactylation site, K124 mutagenesis, RIP, mRNA stability, co-IP, inhibitor, and in vivo proliferation\",\n      \"pmids\": [\"40145796\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct SERBP1–MAD2L1 mRNA element not mapped\", \"Single lab\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identified MAD2L1 as a NANOG partner promoting NANOG nuclear localization, stemness, and carboplatin resistance in lung cancer.\",\n      \"evidence\": \"Co-IP, NANOG localization imaging, knockdown/overexpression, viability/stemness assays, and xenograft\",\n      \"pmids\": [\"40233918\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural basis of MAD2L1–NANOG binding unknown\", \"Relationship to mitotic function not addressed\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Extended MAD2L1 transcriptional control to a non-cancer context, with lncRNA SNHG8 recruiting E2F1 to the MAD2L1 promoter to drive cardiac fibrosis.\",\n      \"evidence\": \"RIP, ChIP of E2F1 at promoter, gain/loss-of-function, and in vivo SNHG8 knockout cardiac fibrosis model\",\n      \"pmids\": [\"41109373\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether E2F1 directly binds MAD2L1 promoter independent of SNHG8 unclear\", \"Single lab\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How MAD2L1's canonical SAC function mechanistically intersects with its newly described oncogenic interactions (NANOG, TYK2/STAT3) and the multiple convergent transcriptional/post-transcriptional control inputs remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking mitotic and non-mitotic roles\", \"Structural details of MAD2L1 complexes in human cells not resolved in corpus\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0060089\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [1]},\n      {\"term_id\": \"GO:0005635\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [0, 2, 4]}\n    ],\n    \"complexes\": [\"MAD1-MAD2 complex\"],\n    \"partners\": [\"MAD1L1\", \"NANOG\", \"TYK2\", \"STAT3\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"tie","faith_supported":7,"faith_total":7,"faith_pct":100.0}}