{"gene":"MACROH2A2","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":2001,"finding":"MACROH2A2 is a second macroH2A gene on human chromosome 10, encoding a protein with 68% amino acid identity to macroH2A1.2. It lacks the leucine zipper motif present in macroH2A1. By immunofluorescence, MACROH2A2 localizes to the inactive X chromosome in female cell nuclei, forming a Macro Chromatin Body co-localizing with macroH2A1.","method":"Gene cloning, sequence analysis, immunofluorescence on mouse tissue sections","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct cloning and localization by immunofluorescence, replicated in parallel by Chadwick & Willard 2001","pmids":["11262398"],"is_preprint":false},{"year":2001,"finding":"MacroH2A2, like macroH2A1, forms a Macro Chromatin Body coincident with an X chromosome in female nuclei and co-localizes with macroH2A1 on the inactive X chromosome. Unlike macroH2A1, macroH2A2 maps to a different chromosomal locus (consistent with chromosome 10).","method":"Immunofluorescence with epitope-tagged constructs, co-localization with macroH2A1 antibody","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct immunofluorescence localization, independently replicated by Costanzi & Pehrson 2001","pmids":["11331621"],"is_preprint":false},{"year":2009,"finding":"MacroH2A1 and macroH2A2, together, occupy promoters of key developmental and cell fate regulator genes in human male pluripotent cells, acting as a repressive mark that overlaps with Polycomb repressive complex 2 (PRC2/H3K27me3). Knockdown of macroH2A2 in zebrafish embryos produces severe developmental phenotypes, demonstrating a functional role in vertebrate development.","method":"Microarray-based chromatin occupancy analysis, co-occupancy with PRC2, morpholino knockdown in zebrafish","journal":"Nature structural & molecular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (ChIP-based, genetic knockdown in vivo), functional developmental phenotype","pmids":["19734898"],"is_preprint":false},{"year":2013,"finding":"MacroH2A2 is the predominant barrier to somatic cell reprogramming to induced pluripotency among macroH2A isoforms. MacroH2A1 and macroH2A2 co-occupy pluripotency genes together with H3K27me3 in wild-type fibroblasts, particularly at target genes of the H3K27me3 demethylase UTX, which are reactivated early in iPS reprogramming. Loss of both macroH2A isoforms (dKO) in differentiated cells reduces the epigenetic barrier, allowing more efficient reprogramming.","method":"macroH2A double-knockout mouse fibroblasts, iPS reprogramming assays, ChIP-seq for macroH2A1/2 and H3K27me3, isoform rescue experiments","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockout + genomic ChIP-seq + isoform-specific rescue, multiple orthogonal approaches","pmids":["23463008"],"is_preprint":false},{"year":2014,"finding":"MacroH2A1 and macroH2A2 knockout mice show impaired prenatal and postnatal growth and reduced reproductive efficiency. MacroH2A2-containing nucleosomes substantially overlap in distribution with macroH2A1 and their effects on gene expression can be synergistic or opposing. In adult liver, macroH2A isoforms preferentially regulate lipid metabolism genes including the leptin receptor.","method":"Double knockout mouse model, gene expression profiling in fetal and adult liver, nucleosome distribution analysis","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo knockout with defined phenotypic and transcriptomic readouts, multiple tissues examined","pmids":["25312643"],"is_preprint":false},{"year":2014,"finding":"MacroH2A2 exhibits dynamic exchange at gene promoters in embryonic stem cells (particularly highly transcribed genes), while large intergenic blocks of macroH2A2 are stably associated. Upon differentiation to fibroblasts, macroH2A2 is gained in additional stable blocks in gene-poor regions and turnover at promoters is dampened.","method":"Pulse-chase genome-wide histone dynamics (SNAP-tag pulse labeling) in murine ES cells and somatic tissues","journal":"PLoS genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genome-wide pulse-chase method, single lab, novel approach with clear mechanistic insight","pmids":["25102063"],"is_preprint":false},{"year":2014,"finding":"Plcγ1 signaling downstream of Epo receptor activates macroH2A2 (H2afy2) expression, and macroH2A2 is a downstream effector of Plcγ1 required for erythroid maturation. Knockdown of macroH2A2 recapitulates the defect in erythroid differentiation caused by Plcγ1 inactivation.","method":"shRNA knockdown of Plcγ1 and macroH2A2 in erythroid progenitors, colony-forming assays, transcriptomics/DNA methylation analysis","journal":"Cell death and differentiation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis by knockdown rescue, cellular differentiation phenotype, single lab","pmids":["25394487"],"is_preprint":false},{"year":2018,"finding":"The crystal structure of the macrodomain of human macroH2A2 at 1.7 Å resolution reveals that its putative binding pocket exhibits marked structural differences compared with macroH2A1.1, rendering macroH2A2 unable to bind ADP-ribose. Quantitative binding assays confirm this specificity is conserved across vertebrate macroH2A isoforms. The unstructured linker region (common to all macroH2A proteins) exerts a repressive effect on PARP1-dependent chromatin relaxation upon DNA damage. The macroH2A linker alone is sufficient to rescue heterochromatin architecture in macroH2A-deficient cells.","method":"Crystal structure at 1.7 Å, quantitative ADP-ribose binding assays, live-cell PARP1 activity assays, domain swap/deletion experiments in cells","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure plus quantitative binding assays plus functional cell-based domain analysis in single rigorous study","pmids":["30177554"],"is_preprint":false},{"year":2018,"finding":"Active transcription defines the boundary of macroH2A2 chromatin domains via a 'pruning' mechanism: macroH2A2 is first broadly deposited genome-wide but is subsequently removed from actively transcribed regions by the FACT complex (facilitates chromatin transcription). Chemical inhibition of transcription counteracts pruning. Locus-specific gene activation depletes pre-existing macroH2A2, while gene silencing triggers ectopic macroH2A2 accumulation.","method":"Temporal genomic profiling (ChIP-seq) in macroH2A-null fibroblasts reconstituted with macroH2A2, chemical transcription inhibition, locus-specific transcriptional manipulation, FACT complex depletion","journal":"Nature structural & molecular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal approaches (genomic profiling, pharmacological, genetic), mechanistic identification of FACT as mediator","pmids":["30291361"],"is_preprint":false},{"year":2020,"finding":"LSH (chromatin remodeling protein) specifically induces macroH2A2 deposition into chromatin in an ATP-dependent manner. LSH-mediated macroH2A2 deposition is required for transcriptional repression at target loci. ICF4 syndrome mutations in LSH fail to induce macroH2A2 deposition, and ICF4 patient cells display reduced macroH2A2 enrichment and transcriptional reactivation.","method":"Chemical-induced proximity (CIP) tethering of LSH to engineered locus, ChIP-seq for macroH2A, siRNA knockdown of macroH2A, ICF4 patient cell analysis, ATP-dependence assay","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (CIP, ChIP-seq, siRNA, patient cells), mechanistic pathway placement","pmids":["33159050"],"is_preprint":false},{"year":2022,"finding":"Inducible overexpression of macroH2A2 in vivo suppresses metastasis by enforcing a reversible growth arrest of disseminated cancer cells (dormancy). This dormancy program inhibits cell cycle and oncogenic signaling programs while up-regulating dormancy and senescence-associated inflammatory cytokines, and does not require dormancy-regulating transcription factors DEC2 or NR2F1.","method":"In vivo PDX models with inducible macroH2A2 expression, transcriptomic analysis, in vivo metastasis assays, DEC2/NR2F1 loss-of-function","journal":"Science advances","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo gain-of-function with transcriptomics, single lab study","pmids":["36459552"],"is_preprint":false},{"year":2022,"finding":"MacroH2A1.2 and macroH2A2 modulate enhancer-promoter contact frequency and enhancer activity in hepatoblastoma cells. Their removal affects NF-κB-mediated transcriptional responses to TNFα (facilitating the response) and suppresses response to IFN-γ. MacroH2A2 has a stronger contribution to gene repression than macroH2A1.2.","method":"Knockout of macroH2A1.2 and macroH2A2 in hepatoblastoma cells, Hi-C/chromatin conformation analysis, transcriptomic response to cytokines","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with chromatin conformation and transcriptomic readouts, single lab","pmids":["35732123"],"is_preprint":false},{"year":2023,"finding":"MacroH2A2 shapes chromatin accessibility at enhancer elements to antagonize transcriptional programs of self-renewal in glioblastoma. MacroH2A2 also sensitizes cells to small molecule-mediated cell death via activation of a viral mimicry response. These findings are based on patient-derived in vitro and in vivo glioblastoma models.","method":"ATAC-seq for chromatin accessibility, transcriptomic profiling, patient-derived xenograft in vivo models, loss-of-function studies","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple omics approaches plus in vivo validation, single lab","pmids":["37244935"],"is_preprint":false},{"year":2023,"finding":"MacroH2A2 marks a subset of inactive enhancers (macro-bound enhancers) lacking H3K27ac in a cell type-specific manner, maintaining cell identity. MacroH2A2 acts as a negative regulator of BRD4 chromatin occupancy at these enhancers. MacroH2A deficiency in mammary stem cells facilitates increased activity of transcription factors associated with stem cell activity.","method":"ChIP-seq for macroH2A and H3K27ac, BRD4 occupancy assays, single-cell ATAC-seq in mouse mammary stem cells, loss-of-function","journal":"Communications biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multi-omics with functional validation, single lab","pmids":["36823213"],"is_preprint":false},{"year":2024,"finding":"MacroH2A1, but not macroH2A2, regulates the number of replication foci and DNA loop sizes (replicons) on the inactive X chromosome by interacting with the replicative helicase (MCM complex). This interaction is mediated by a phenylalanine residue in macroH2A1 that is not conserved in macroH2A2, and maps to the C-terminus of Mcm3. MacroH2A2-containing nucleosomes slow replication progression rate on the Xi (shared with macroH2A1), but macroH2A2 does NOT regulate helicase loading.","method":"Knockdown/knockout of individual macroH2A isoforms, replication focus imaging, DNA fiber assays, Co-IP of macroH2A1 with MCM helicase, domain mutagenesis (phenylalanine substitution)","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1 / Strong — mutagenesis identifying specific residue plus Co-IP plus functional replication assays; negative result for macroH2A2/helicase interaction is mechanistically informative","pmids":["39189450"],"is_preprint":false},{"year":2024,"finding":"MacroH2A2 suppresses breast cancer malignancy by repressing TM4SF1 expression. The mH2A2/TM4SF1 axis controls the AKT/NF-κB signaling pathway; macroH2A2 knockdown activates AKT/NF-κB and increases MMP13 expression and secretion. Overexpression of macroH2A2 reduced tumor growth and lung metastasis in vivo.","method":"Knockdown/overexpression of macroH2A2 in breast cancer cells, microarray gene expression, TM4SF1 rescue experiments, in vivo tumor and metastasis models, AKT/NF-κB pathway analysis","journal":"Molecular carcinogenesis","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis experiments (TM4SF1 rescue of mH2A2 KD) plus in vivo validation, single lab","pmids":["38251858"],"is_preprint":false}],"current_model":"MacroH2A2 is a replication-independent histone H2A variant that incorporates into nucleosomes and, via its unstructured linker region, restricts chromatin plasticity and PARP1-dependent relaxation; its macrodomain cannot bind ADP-ribose (unlike macroH2A1.1, established by crystal structure); it is deposited into chromatin in an ATP-dependent manner by the chromatin remodeler LSH and is removed from actively transcribed regions by the FACT complex to establish repressive chromatin domains; it co-occupies developmental gene promoters and enhancers with PRC2/H3K27me3, acts as the predominant epigenetic barrier to somatic reprogramming, regulates erythroid differentiation downstream of Plcγ1/EpoR signaling, suppresses oncogenic self-renewal and metastatic outgrowth (partly via a TM4SF1/AKT/NF-κB axis), and—unlike macroH2A1—does not interact with the MCM replicative helicase and thus does not regulate replication origin licensing on the inactive X chromosome."},"narrative":{"mechanistic_narrative":"MACROH2A2 (H2afy2) is a replication-independent histone H2A variant that incorporates into nucleosomes to establish repressive chromatin domains and restrict chromatin plasticity during development, differentiation, and tumor suppression [PMID:11262398, PMID:19734898, PMID:30177554]. It localizes to the inactive X chromosome, forming a Macro Chromatin Body that co-localizes with macroH2A1 [PMID:11262398, PMID:11331621], and broadly co-occupies developmental and pluripotency gene promoters together with PRC2/H3K27me3 [PMID:19734898, PMID:23463008]. Its repressive function maps largely to the unstructured linker region, which restrains PARP1-dependent chromatin relaxation and is sufficient to rescue heterochromatin architecture in macroH2A-deficient cells; in contrast, its macrodomain is structurally incapable of binding ADP-ribose, distinguishing it from macroH2A1.1 [PMID:30177554]. MacroH2A2 is deposited into chromatin in an ATP-dependent manner by the chromatin remodeler LSH to enforce transcriptional repression, a pathway disrupted by ICF4-causing LSH mutations [PMID:33159050], and its genomic boundaries are sculpted by a transcription-coupled 'pruning' mechanism in which the FACT complex removes it from actively transcribed regions [PMID:30291361]. Functionally, macroH2A2 is the predominant macroH2A barrier to somatic reprogramming [PMID:23463008], acts downstream of Plcγ1/EpoR signaling in erythroid maturation [PMID:25394487], and represses self-renewal and metastatic outgrowth in multiple cancers, in part by shaping enhancer accessibility, antagonizing BRD4, and repressing a TM4SF1/AKT/NF-κB axis [PMID:36823213, PMID:38251858, PMID:36459552]. Unlike macroH2A1, macroH2A2 does not interact with the MCM replicative helicase and does not regulate origin licensing on the inactive X, though its nucleosomes still slow replication progression there [PMID:39189450].","teleology":[{"year":2001,"claim":"Established MACROH2A2 as a distinct second macroH2A gene and localized it to repressive chromatin, framing it as a candidate epigenetic silencer rather than a redundant copy of macroH2A1.","evidence":"Gene cloning, sequence analysis, and immunofluorescence co-localization with macroH2A1 on the inactive X chromosome","pmids":["11262398","11331621"],"confidence":"High","gaps":["Functional consequence of inactive-X localization not tested","No identification of deposition machinery or partners"]},{"year":2009,"claim":"Showed macroH2A2 occupies developmental gene promoters alongside PRC2/H3K27me3 and is required for vertebrate development, placing it within a Polycomb-overlapping repressive program.","evidence":"Microarray chromatin occupancy with PRC2 co-occupancy analysis and morpholino knockdown in zebrafish","pmids":["19734898"],"confidence":"High","gaps":["Did not separate macroH2A1 from macroH2A2 contributions","Mechanism of PRC2 co-occupancy unresolved"]},{"year":2013,"claim":"Identified macroH2A2 as the predominant macroH2A isoform barrier to somatic reprogramming, linking its chromatin marking to maintenance of differentiated cell identity.","evidence":"macroH2A double-knockout fibroblasts, iPS reprogramming assays, ChIP-seq, and isoform-specific rescue","pmids":["23463008"],"confidence":"High","gaps":["Did not define how macroH2A2 is targeted to pluripotency genes","Relationship to UTX-dependent reactivation only correlative"]},{"year":2014,"claim":"Defined in vivo physiological roles (growth, reproduction, lipid metabolism), chromatin exchange dynamics, and a signaling-linked differentiation role downstream of Plcγ1/EpoR in erythropoiesis.","evidence":"Double-knockout mouse phenotyping and transcriptomics; SNAP-tag pulse-chase histone dynamics; shRNA epistasis in erythroid progenitors","pmids":["25312643","25102063","25394487"],"confidence":"Medium","gaps":["Erythroid and metabolic findings from single labs","Molecular link between Plcγ1 signaling and macroH2A2 expression not resolved"]},{"year":2018,"claim":"Resolved the macrodomain structure showing macroH2A2 cannot bind ADP-ribose, and assigned its repressive activity to the unstructured linker that restrains PARP1-dependent chromatin relaxation.","evidence":"1.7 Å crystal structure, quantitative ADP-ribose binding assays, live-cell PARP1 activity assays, and domain swap/deletion in cells","pmids":["30177554"],"confidence":"High","gaps":["Functional role of the non-binding macrodomain pocket unknown","How linker mechanically restricts PARP1 not structurally defined"]},{"year":2018,"claim":"Revealed that macroH2A2 domain boundaries are set by transcription-coupled 'pruning', identifying FACT as the activity that removes it from active genes.","evidence":"Temporal ChIP-seq in reconstituted macroH2A-null fibroblasts, chemical transcription inhibition, locus-specific manipulation, and FACT depletion","pmids":["30291361"],"confidence":"High","gaps":["How FACT distinguishes macroH2A2 from canonical H2A not defined","Fate of evicted macroH2A2 unknown"]},{"year":2020,"claim":"Identified the deposition machinery: LSH catalyzes ATP-dependent macroH2A2 incorporation required for repression, connecting macroH2A2 loss to ICF4 syndrome.","evidence":"Chemical-induced proximity tethering of LSH, ChIP-seq, siRNA, ATP-dependence assays, and ICF4 patient cell analysis","pmids":["33159050"],"confidence":"High","gaps":["Whether LSH acts alone or with cofactors not resolved","Substrate selectivity for macroH2A2 versus macroH2A1 unclear"]},{"year":2022,"claim":"Extended macroH2A2 function to tumor suppression via enforcement of disseminated-cell dormancy and modulation of enhancer-promoter contacts and cytokine responses.","evidence":"Inducible in vivo PDX overexpression with metastasis assays and DEC2/NR2F1 loss-of-function; KO with Hi-C and cytokine transcriptomics in hepatoblastoma","pmids":["36459552","35732123"],"confidence":"Medium","gaps":["Dormancy program effectors downstream of macroH2A2 not identified","Single-lab studies in specific cancer contexts"]},{"year":2023,"claim":"Showed macroH2A2 enforces cell identity and suppresses self-renewal by closing enhancer chromatin and antagonizing BRD4, with a parallel viral-mimicry sensitization in glioblastoma.","evidence":"ATAC-seq, ChIP-seq for macroH2A/H3K27ac, BRD4 occupancy, scATAC-seq, and patient-derived in vitro/in vivo loss-of-function models","pmids":["37244935","36823213"],"confidence":"Medium","gaps":["Mechanism of BRD4 exclusion not biochemically defined","Viral mimicry trigger downstream of macroH2A2 unresolved"]},{"year":2024,"claim":"Distinguished macroH2A2 from macroH2A1 in replication control and identified a tumor-suppressive transcriptional axis, refining isoform-specific mechanism.","evidence":"Isoform-specific knockdown/knockout, replication focus imaging, DNA fiber and Co-IP assays with residue mutagenesis; macroH2A2 KD/overexpression with TM4SF1 rescue and in vivo tumor models","pmids":["39189450","38251858"],"confidence":"High","gaps":["macroH2A2 lacks the MCM-interacting residue but its full replication role beyond slowing progression unclear","TM4SF1/AKT/NF-κB axis validated in single lab"]},{"year":null,"claim":"How macroH2A2's repressive linker, LSH-mediated deposition, and FACT-mediated removal are coordinated to produce locus- and cell-type-specific chromatin domains, and what distinguishes its function from macroH2A1 genome-wide, remains incompletely defined.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structure of full macroH2A2 nucleosome with LSH or FACT","Determinants of isoform-specific targeting unknown","Direct protein partners of the macrodomain unidentified"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[0,7]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[2,8,9]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[7]}],"localization":[{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[0,1,14]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,1]},{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[8,9]}],"pathway":[{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[8,9]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[2,13]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[2,3,6]}],"complexes":["nucleosome","Macro Chromatin Body"],"partners":["MACROH2A1","LSH","FACT","TM4SF1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9P0M6","full_name":"Core histone macro-H2A.2","aliases":[],"length_aa":372,"mass_kda":40.1,"function":"Variant histone H2A which replaces conventional H2A in a subset of nucleosomes where it represses transcription. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. May be involved in stable X chromosome inactivation","subcellular_location":"Nucleus; Chromosome","url":"https://www.uniprot.org/uniprotkb/Q9P0M6/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MACROH2A2","classification":"Not Classified","n_dependent_lines":27,"n_total_lines":1208,"dependency_fraction":0.022350993377483443},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"HMGN2","stoichiometry":10.0},{"gene":"NUMA1","stoichiometry":10.0},{"gene":"HMGN5","stoichiometry":4.0},{"gene":"NUCKS1","stoichiometry":4.0},{"gene":"H1F0","stoichiometry":0.2},{"gene":"H2AFZ","stoichiometry":0.2},{"gene":"HIST2H2BE","stoichiometry":0.2},{"gene":"HMGA1","stoichiometry":0.2},{"gene":"MED27","stoichiometry":0.2},{"gene":"NECAP1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/MACROH2A2","total_profiled":1310},"omim":[{"mim_id":"616141","title":"MACRO H2A.2 HISTONE; MACROH2A2","url":"https://www.omim.org/entry/616141"},{"mim_id":"610054","title":"MACRO H2A.1 HISTONE; MACROH2A1","url":"https://www.omim.org/entry/610054"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/MACROH2A2"},"hgnc":{"alias_symbol":[],"prev_symbol":["H2AFY2"]},"alphafold":{"accession":"Q9P0M6","domains":[{"cath_id":"1.10.20.10","chopping":"15-94","consensus_level":"high","plddt":94.4065,"start":15,"end":94},{"cath_id":"3.40.220.10","chopping":"182-367","consensus_level":"high","plddt":92.8203,"start":182,"end":367}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9P0M6","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9P0M6-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9P0M6-F1-predicted_aligned_error_v6.png","plddt_mean":82.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MACROH2A2","jax_strain_url":"https://www.jax.org/strain/search?query=MACROH2A2"},"sequence":{"accession":"Q9P0M6","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9P0M6.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9P0M6/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9P0M6"}},"corpus_meta":[{"pmid":"23463008","id":"PMC_23463008","title":"MacroH2A 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It lacks the leucine zipper motif present in macroH2A1. By immunofluorescence, MACROH2A2 localizes to the inactive X chromosome in female cell nuclei, forming a Macro Chromatin Body co-localizing with macroH2A1.\",\n      \"method\": \"Gene cloning, sequence analysis, immunofluorescence on mouse tissue sections\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct cloning and localization by immunofluorescence, replicated in parallel by Chadwick & Willard 2001\",\n      \"pmids\": [\"11262398\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"MacroH2A2, like macroH2A1, forms a Macro Chromatin Body coincident with an X chromosome in female nuclei and co-localizes with macroH2A1 on the inactive X chromosome. Unlike macroH2A1, macroH2A2 maps to a different chromosomal locus (consistent with chromosome 10).\",\n      \"method\": \"Immunofluorescence with epitope-tagged constructs, co-localization with macroH2A1 antibody\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct immunofluorescence localization, independently replicated by Costanzi & Pehrson 2001\",\n      \"pmids\": [\"11331621\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"MacroH2A1 and macroH2A2, together, occupy promoters of key developmental and cell fate regulator genes in human male pluripotent cells, acting as a repressive mark that overlaps with Polycomb repressive complex 2 (PRC2/H3K27me3). Knockdown of macroH2A2 in zebrafish embryos produces severe developmental phenotypes, demonstrating a functional role in vertebrate development.\",\n      \"method\": \"Microarray-based chromatin occupancy analysis, co-occupancy with PRC2, morpholino knockdown in zebrafish\",\n      \"journal\": \"Nature structural & molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (ChIP-based, genetic knockdown in vivo), functional developmental phenotype\",\n      \"pmids\": [\"19734898\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"MacroH2A2 is the predominant barrier to somatic cell reprogramming to induced pluripotency among macroH2A isoforms. MacroH2A1 and macroH2A2 co-occupy pluripotency genes together with H3K27me3 in wild-type fibroblasts, particularly at target genes of the H3K27me3 demethylase UTX, which are reactivated early in iPS reprogramming. Loss of both macroH2A isoforms (dKO) in differentiated cells reduces the epigenetic barrier, allowing more efficient reprogramming.\",\n      \"method\": \"macroH2A double-knockout mouse fibroblasts, iPS reprogramming assays, ChIP-seq for macroH2A1/2 and H3K27me3, isoform rescue experiments\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockout + genomic ChIP-seq + isoform-specific rescue, multiple orthogonal approaches\",\n      \"pmids\": [\"23463008\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"MacroH2A1 and macroH2A2 knockout mice show impaired prenatal and postnatal growth and reduced reproductive efficiency. MacroH2A2-containing nucleosomes substantially overlap in distribution with macroH2A1 and their effects on gene expression can be synergistic or opposing. In adult liver, macroH2A isoforms preferentially regulate lipid metabolism genes including the leptin receptor.\",\n      \"method\": \"Double knockout mouse model, gene expression profiling in fetal and adult liver, nucleosome distribution analysis\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo knockout with defined phenotypic and transcriptomic readouts, multiple tissues examined\",\n      \"pmids\": [\"25312643\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"MacroH2A2 exhibits dynamic exchange at gene promoters in embryonic stem cells (particularly highly transcribed genes), while large intergenic blocks of macroH2A2 are stably associated. Upon differentiation to fibroblasts, macroH2A2 is gained in additional stable blocks in gene-poor regions and turnover at promoters is dampened.\",\n      \"method\": \"Pulse-chase genome-wide histone dynamics (SNAP-tag pulse labeling) in murine ES cells and somatic tissues\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genome-wide pulse-chase method, single lab, novel approach with clear mechanistic insight\",\n      \"pmids\": [\"25102063\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Plcγ1 signaling downstream of Epo receptor activates macroH2A2 (H2afy2) expression, and macroH2A2 is a downstream effector of Plcγ1 required for erythroid maturation. Knockdown of macroH2A2 recapitulates the defect in erythroid differentiation caused by Plcγ1 inactivation.\",\n      \"method\": \"shRNA knockdown of Plcγ1 and macroH2A2 in erythroid progenitors, colony-forming assays, transcriptomics/DNA methylation analysis\",\n      \"journal\": \"Cell death and differentiation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis by knockdown rescue, cellular differentiation phenotype, single lab\",\n      \"pmids\": [\"25394487\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The crystal structure of the macrodomain of human macroH2A2 at 1.7 Å resolution reveals that its putative binding pocket exhibits marked structural differences compared with macroH2A1.1, rendering macroH2A2 unable to bind ADP-ribose. Quantitative binding assays confirm this specificity is conserved across vertebrate macroH2A isoforms. The unstructured linker region (common to all macroH2A proteins) exerts a repressive effect on PARP1-dependent chromatin relaxation upon DNA damage. The macroH2A linker alone is sufficient to rescue heterochromatin architecture in macroH2A-deficient cells.\",\n      \"method\": \"Crystal structure at 1.7 Å, quantitative ADP-ribose binding assays, live-cell PARP1 activity assays, domain swap/deletion experiments in cells\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure plus quantitative binding assays plus functional cell-based domain analysis in single rigorous study\",\n      \"pmids\": [\"30177554\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Active transcription defines the boundary of macroH2A2 chromatin domains via a 'pruning' mechanism: macroH2A2 is first broadly deposited genome-wide but is subsequently removed from actively transcribed regions by the FACT complex (facilitates chromatin transcription). Chemical inhibition of transcription counteracts pruning. Locus-specific gene activation depletes pre-existing macroH2A2, while gene silencing triggers ectopic macroH2A2 accumulation.\",\n      \"method\": \"Temporal genomic profiling (ChIP-seq) in macroH2A-null fibroblasts reconstituted with macroH2A2, chemical transcription inhibition, locus-specific transcriptional manipulation, FACT complex depletion\",\n      \"journal\": \"Nature structural & molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal approaches (genomic profiling, pharmacological, genetic), mechanistic identification of FACT as mediator\",\n      \"pmids\": [\"30291361\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"LSH (chromatin remodeling protein) specifically induces macroH2A2 deposition into chromatin in an ATP-dependent manner. LSH-mediated macroH2A2 deposition is required for transcriptional repression at target loci. ICF4 syndrome mutations in LSH fail to induce macroH2A2 deposition, and ICF4 patient cells display reduced macroH2A2 enrichment and transcriptional reactivation.\",\n      \"method\": \"Chemical-induced proximity (CIP) tethering of LSH to engineered locus, ChIP-seq for macroH2A, siRNA knockdown of macroH2A, ICF4 patient cell analysis, ATP-dependence assay\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (CIP, ChIP-seq, siRNA, patient cells), mechanistic pathway placement\",\n      \"pmids\": [\"33159050\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Inducible overexpression of macroH2A2 in vivo suppresses metastasis by enforcing a reversible growth arrest of disseminated cancer cells (dormancy). This dormancy program inhibits cell cycle and oncogenic signaling programs while up-regulating dormancy and senescence-associated inflammatory cytokines, and does not require dormancy-regulating transcription factors DEC2 or NR2F1.\",\n      \"method\": \"In vivo PDX models with inducible macroH2A2 expression, transcriptomic analysis, in vivo metastasis assays, DEC2/NR2F1 loss-of-function\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo gain-of-function with transcriptomics, single lab study\",\n      \"pmids\": [\"36459552\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"MacroH2A1.2 and macroH2A2 modulate enhancer-promoter contact frequency and enhancer activity in hepatoblastoma cells. Their removal affects NF-κB-mediated transcriptional responses to TNFα (facilitating the response) and suppresses response to IFN-γ. MacroH2A2 has a stronger contribution to gene repression than macroH2A1.2.\",\n      \"method\": \"Knockout of macroH2A1.2 and macroH2A2 in hepatoblastoma cells, Hi-C/chromatin conformation analysis, transcriptomic response to cytokines\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with chromatin conformation and transcriptomic readouts, single lab\",\n      \"pmids\": [\"35732123\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MacroH2A2 shapes chromatin accessibility at enhancer elements to antagonize transcriptional programs of self-renewal in glioblastoma. MacroH2A2 also sensitizes cells to small molecule-mediated cell death via activation of a viral mimicry response. These findings are based on patient-derived in vitro and in vivo glioblastoma models.\",\n      \"method\": \"ATAC-seq for chromatin accessibility, transcriptomic profiling, patient-derived xenograft in vivo models, loss-of-function studies\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple omics approaches plus in vivo validation, single lab\",\n      \"pmids\": [\"37244935\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MacroH2A2 marks a subset of inactive enhancers (macro-bound enhancers) lacking H3K27ac in a cell type-specific manner, maintaining cell identity. MacroH2A2 acts as a negative regulator of BRD4 chromatin occupancy at these enhancers. MacroH2A deficiency in mammary stem cells facilitates increased activity of transcription factors associated with stem cell activity.\",\n      \"method\": \"ChIP-seq for macroH2A and H3K27ac, BRD4 occupancy assays, single-cell ATAC-seq in mouse mammary stem cells, loss-of-function\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multi-omics with functional validation, single lab\",\n      \"pmids\": [\"36823213\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MacroH2A1, but not macroH2A2, regulates the number of replication foci and DNA loop sizes (replicons) on the inactive X chromosome by interacting with the replicative helicase (MCM complex). This interaction is mediated by a phenylalanine residue in macroH2A1 that is not conserved in macroH2A2, and maps to the C-terminus of Mcm3. MacroH2A2-containing nucleosomes slow replication progression rate on the Xi (shared with macroH2A1), but macroH2A2 does NOT regulate helicase loading.\",\n      \"method\": \"Knockdown/knockout of individual macroH2A isoforms, replication focus imaging, DNA fiber assays, Co-IP of macroH2A1 with MCM helicase, domain mutagenesis (phenylalanine substitution)\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — mutagenesis identifying specific residue plus Co-IP plus functional replication assays; negative result for macroH2A2/helicase interaction is mechanistically informative\",\n      \"pmids\": [\"39189450\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MacroH2A2 suppresses breast cancer malignancy by repressing TM4SF1 expression. The mH2A2/TM4SF1 axis controls the AKT/NF-κB signaling pathway; macroH2A2 knockdown activates AKT/NF-κB and increases MMP13 expression and secretion. Overexpression of macroH2A2 reduced tumor growth and lung metastasis in vivo.\",\n      \"method\": \"Knockdown/overexpression of macroH2A2 in breast cancer cells, microarray gene expression, TM4SF1 rescue experiments, in vivo tumor and metastasis models, AKT/NF-κB pathway analysis\",\n      \"journal\": \"Molecular carcinogenesis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis experiments (TM4SF1 rescue of mH2A2 KD) plus in vivo validation, single lab\",\n      \"pmids\": [\"38251858\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MacroH2A2 is a replication-independent histone H2A variant that incorporates into nucleosomes and, via its unstructured linker region, restricts chromatin plasticity and PARP1-dependent relaxation; its macrodomain cannot bind ADP-ribose (unlike macroH2A1.1, established by crystal structure); it is deposited into chromatin in an ATP-dependent manner by the chromatin remodeler LSH and is removed from actively transcribed regions by the FACT complex to establish repressive chromatin domains; it co-occupies developmental gene promoters and enhancers with PRC2/H3K27me3, acts as the predominant epigenetic barrier to somatic reprogramming, regulates erythroid differentiation downstream of Plcγ1/EpoR signaling, suppresses oncogenic self-renewal and metastatic outgrowth (partly via a TM4SF1/AKT/NF-κB axis), and—unlike macroH2A1—does not interact with the MCM replicative helicase and thus does not regulate replication origin licensing on the inactive X chromosome.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"MACROH2A2 (H2afy2) is a replication-independent histone H2A variant that incorporates into nucleosomes to establish repressive chromatin domains and restrict chromatin plasticity during development, differentiation, and tumor suppression [#0, #2, #7]. It localizes to the inactive X chromosome, forming a Macro Chromatin Body that co-localizes with macroH2A1 [#0, #1], and broadly co-occupies developmental and pluripotency gene promoters together with PRC2/H3K27me3 [#2, #3]. Its repressive function maps largely to the unstructured linker region, which restrains PARP1-dependent chromatin relaxation and is sufficient to rescue heterochromatin architecture in macroH2A-deficient cells; in contrast, its macrodomain is structurally incapable of binding ADP-ribose, distinguishing it from macroH2A1.1 [#7]. MacroH2A2 is deposited into chromatin in an ATP-dependent manner by the chromatin remodeler LSH to enforce transcriptional repression, a pathway disrupted by ICF4-causing LSH mutations [#9], and its genomic boundaries are sculpted by a transcription-coupled 'pruning' mechanism in which the FACT complex removes it from actively transcribed regions [#8]. Functionally, macroH2A2 is the predominant macroH2A barrier to somatic reprogramming [#3], acts downstream of Plcγ1/EpoR signaling in erythroid maturation [#6], and represses self-renewal and metastatic outgrowth in multiple cancers, in part by shaping enhancer accessibility, antagonizing BRD4, and repressing a TM4SF1/AKT/NF-κB axis [#13, #15, #10]. Unlike macroH2A1, macroH2A2 does not interact with the MCM replicative helicase and does not regulate origin licensing on the inactive X, though its nucleosomes still slow replication progression there [#14].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Established MACROH2A2 as a distinct second macroH2A gene and localized it to repressive chromatin, framing it as a candidate epigenetic silencer rather than a redundant copy of macroH2A1.\",\n      \"evidence\": \"Gene cloning, sequence analysis, and immunofluorescence co-localization with macroH2A1 on the inactive X chromosome\",\n      \"pmids\": [\"11262398\", \"11331621\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of inactive-X localization not tested\", \"No identification of deposition machinery or partners\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Showed macroH2A2 occupies developmental gene promoters alongside PRC2/H3K27me3 and is required for vertebrate development, placing it within a Polycomb-overlapping repressive program.\",\n      \"evidence\": \"Microarray chromatin occupancy with PRC2 co-occupancy analysis and morpholino knockdown in zebrafish\",\n      \"pmids\": [\"19734898\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not separate macroH2A1 from macroH2A2 contributions\", \"Mechanism of PRC2 co-occupancy unresolved\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Identified macroH2A2 as the predominant macroH2A isoform barrier to somatic reprogramming, linking its chromatin marking to maintenance of differentiated cell identity.\",\n      \"evidence\": \"macroH2A double-knockout fibroblasts, iPS reprogramming assays, ChIP-seq, and isoform-specific rescue\",\n      \"pmids\": [\"23463008\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define how macroH2A2 is targeted to pluripotency genes\", \"Relationship to UTX-dependent reactivation only correlative\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Defined in vivo physiological roles (growth, reproduction, lipid metabolism), chromatin exchange dynamics, and a signaling-linked differentiation role downstream of Plcγ1/EpoR in erythropoiesis.\",\n      \"evidence\": \"Double-knockout mouse phenotyping and transcriptomics; SNAP-tag pulse-chase histone dynamics; shRNA epistasis in erythroid progenitors\",\n      \"pmids\": [\"25312643\", \"25102063\", \"25394487\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Erythroid and metabolic findings from single labs\", \"Molecular link between Plcγ1 signaling and macroH2A2 expression not resolved\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Resolved the macrodomain structure showing macroH2A2 cannot bind ADP-ribose, and assigned its repressive activity to the unstructured linker that restrains PARP1-dependent chromatin relaxation.\",\n      \"evidence\": \"1.7 Å crystal structure, quantitative ADP-ribose binding assays, live-cell PARP1 activity assays, and domain swap/deletion in cells\",\n      \"pmids\": [\"30177554\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional role of the non-binding macrodomain pocket unknown\", \"How linker mechanically restricts PARP1 not structurally defined\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Revealed that macroH2A2 domain boundaries are set by transcription-coupled 'pruning', identifying FACT as the activity that removes it from active genes.\",\n      \"evidence\": \"Temporal ChIP-seq in reconstituted macroH2A-null fibroblasts, chemical transcription inhibition, locus-specific manipulation, and FACT depletion\",\n      \"pmids\": [\"30291361\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How FACT distinguishes macroH2A2 from canonical H2A not defined\", \"Fate of evicted macroH2A2 unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified the deposition machinery: LSH catalyzes ATP-dependent macroH2A2 incorporation required for repression, connecting macroH2A2 loss to ICF4 syndrome.\",\n      \"evidence\": \"Chemical-induced proximity tethering of LSH, ChIP-seq, siRNA, ATP-dependence assays, and ICF4 patient cell analysis\",\n      \"pmids\": [\"33159050\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether LSH acts alone or with cofactors not resolved\", \"Substrate selectivity for macroH2A2 versus macroH2A1 unclear\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Extended macroH2A2 function to tumor suppression via enforcement of disseminated-cell dormancy and modulation of enhancer-promoter contacts and cytokine responses.\",\n      \"evidence\": \"Inducible in vivo PDX overexpression with metastasis assays and DEC2/NR2F1 loss-of-function; KO with Hi-C and cytokine transcriptomics in hepatoblastoma\",\n      \"pmids\": [\"36459552\", \"35732123\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Dormancy program effectors downstream of macroH2A2 not identified\", \"Single-lab studies in specific cancer contexts\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Showed macroH2A2 enforces cell identity and suppresses self-renewal by closing enhancer chromatin and antagonizing BRD4, with a parallel viral-mimicry sensitization in glioblastoma.\",\n      \"evidence\": \"ATAC-seq, ChIP-seq for macroH2A/H3K27ac, BRD4 occupancy, scATAC-seq, and patient-derived in vitro/in vivo loss-of-function models\",\n      \"pmids\": [\"37244935\", \"36823213\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of BRD4 exclusion not biochemically defined\", \"Viral mimicry trigger downstream of macroH2A2 unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Distinguished macroH2A2 from macroH2A1 in replication control and identified a tumor-suppressive transcriptional axis, refining isoform-specific mechanism.\",\n      \"evidence\": \"Isoform-specific knockdown/knockout, replication focus imaging, DNA fiber and Co-IP assays with residue mutagenesis; macroH2A2 KD/overexpression with TM4SF1 rescue and in vivo tumor models\",\n      \"pmids\": [\"39189450\", \"38251858\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"macroH2A2 lacks the MCM-interacting residue but its full replication role beyond slowing progression unclear\", \"TM4SF1/AKT/NF-κB axis validated in single lab\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How macroH2A2's repressive linker, LSH-mediated deposition, and FACT-mediated removal are coordinated to produce locus- and cell-type-specific chromatin domains, and what distinguishes its function from macroH2A1 genome-wide, remains incompletely defined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structure of full macroH2A2 nucleosome with LSH or FACT\", \"Determinants of isoform-specific targeting unknown\", \"Direct protein partners of the macrodomain unidentified\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 7]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [2, 8, 9]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [7]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [0, 1, 14]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [8, 9]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [8, 9]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [2, 13]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [2, 3, 6]}\n    ],\n    \"complexes\": [\"nucleosome\", \"Macro Chromatin Body\"],\n    \"partners\": [\"MACROH2A1\", \"LSH\", \"FACT\", \"TM4SF1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}