{"gene":"SMARCAD1","run_date":"2026-06-10T07:46:35","timeline":{"discoveries":[{"year":2012,"finding":"SMARCAD1 (and its yeast ortholog Fun30) is recruited to DNA double-strand break ends and directly promotes both Exo1- and Sgs1-dependent 5'-to-3' end resection through a mechanism requiring its ATPase activity, facilitating homologous recombination repair.","method":"Chromatin immunoprecipitation at DSBs, ATPase-dead mutant analysis, epistasis with Exo1/Sgs1, camptothecin/PARP inhibitor sensitivity assays","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal genetic and biochemical analysis in both yeast and human cells, ATPase mutant validation, multiple orthogonal methods, replicated across organisms","pmids":["22960744"],"is_preprint":false},{"year":2011,"finding":"SMARCAD1's ATPase activity is required for global deacetylation of histones H3/H4, which promotes H3K9 methylation and heterochromatin establishment; SMARCAD1 associates with KAP1, HDAC1/2, and G9a/GLP, modulates HDAC1-KAP1 interaction at heterochromatin, and directly interacts with PCNA to be recruited to replication sites.","method":"ATPase mutant complementation, Co-immunoprecipitation, histone modification ChIP, live-cell imaging at replication foci, chromosome segregation assay","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (Co-IP, ChIP, ATPase mutant, PCNA interaction), direct interaction with replication machinery demonstrated","pmids":["21549307"],"is_preprint":false},{"year":2018,"finding":"ATM kinase phosphorylates SMARCAD1 at T906 in response to ionizing radiation; this phosphorylation is required for SMARCAD1 recruitment to DSBs, and T906 phosphorylation also enables subsequent ubiquitination of SMARCAD1 at K905 by RING1. Both PTMs are required for SMARCAD1's role in DNA end resection and HR-mediated repair.","method":"Site-directed mutagenesis of T906 and K905, phospho-specific antibodies, Co-immunoprecipitation, IR-induced foci assays, HR reporter assay","journal":"iScience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis plus functional assays in single lab, two orthogonal PTM modifications demonstrated","pmids":["29888761"],"is_preprint":false},{"year":2017,"finding":"SMARCAD1 preferentially binds H3R26-citrullinated histone peptides and co-localizes genome-wide with H3R26Cit; SMARCAD1 occupancy at H3R26Cit sites suppresses H3K9me3 accumulation, and its knockdown increases H3K9me3 at those loci, linking it to maintenance of naive pluripotency.","method":"Histone peptide array binding (384 modifications), ChIP-seq, Smarcad1 knockdown, gene expression analysis, embryoid body and chimera assays","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — histone peptide array plus ChIP-seq and KD phenotype, single lab, multiple orthogonal approaches","pmids":["28355564"],"is_preprint":false},{"year":2017,"finding":"The CUE1 domain of SMARCAD1 directly mediates binding to the RBCC domain of KAP1 (TRIM28); this interaction occurs on chromatin and is required for SMARCAD1 nuclear retention and its association with KAP1 target genes including ZFP and imprinted genes.","method":"Co-immunoprecipitation of endogenous proteins, CUE1 domain mutations in vitro and in vivo, ChIP, nuclear fractionation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct interaction confirmed by in vitro binding with purified proteins plus in vivo Co-IP, domain-mapping mutations, ChIP validation, multiple orthogonal methods","pmids":["29284678"],"is_preprint":false},{"year":2018,"finding":"In Xenopus egg extracts, Smarcad1 is recruited to mismatch-containing DNA in an Msh2-dependent but Mlh1-independent manner, and facilitates nucleosome exclusion around mismatches; it assists mismatch repair when nucleosomes are preassembled on DNA. In yeast, Fun30 deletion combined with MSH6 or MSH3 deletion synergistically increases spontaneous mutations.","method":"Xenopus egg extract chromatin assembly/disassembly assay, immunodepletion, genetic epistasis in yeast (double mutants), nucleosome occupancy assays","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — reconstitution in Xenopus extracts plus yeast genetic epistasis, multiple orthogonal approaches, mechanistic pathway placement","pmids":["29899141"],"is_preprint":false},{"year":2019,"finding":"SMARCAD1 ATPase activity is required for recruitment of MutLα (MLH1-PMS2) to chromatin-bound MutSα (MSH2-MSH6) after alkylating-agent-induced DNA damage; loss of SMARCAD1 impairs this recruitment, suppresses apoptosis, and increases mutation frequency.","method":"SMARCAD1 knockout cells, MNU treatment, co-immunoprecipitation of MutSα and MutLα from chromatin fractions, ATPase-dead mutant complementation, sub-G1/caspase assays","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO plus ATPase mutant rescue, Co-IP from chromatin fractions, single lab with multiple functional readouts","pmids":["31843968"],"is_preprint":false},{"year":2021,"finding":"SMARCAD1 stabilizes active replication forks by preventing accumulation of 53BP1-associated nucleosomes at forks; in SMARCAD1-deficient cells, 53BP1 mediates premature PCNA removal via the PCNA-unloader ATAD5, causing fork stalling and ssDNA accumulation. Loss of 53BP1 rescues these defects but requires BRCA1-mediated fork protection.","method":"SMARCAD1 KO/knockdown, 53BP1 co-depletion epistasis, DNA fiber assays, PCNA/ATAD5 interaction studies, iPOND, genetic rescue experiments","journal":"Science advances","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis (SMARCAD1/53BP1/BRCA1/ATAD5), DNA fiber assay, iPOND, multiple orthogonal methods in single rigorous study","pmids":["33952518"],"is_preprint":false},{"year":2021,"finding":"SMARCAD1 can transfer an entire histone octamer from one DNA segment to another in an ATP-dependent manner (histone octamer exchange), and can also perform de novo nucleosome assembly from histone octamer due to its ability to simultaneously bind all four histones. Cryo-EM reveals that the ATPase domains engage the nucleosome differently from other chromatin remodelers.","method":"In vitro histone exchange assay, de novo nucleosome assembly assay, cryo-EM structure determination, biochemical binding assays","journal":"Science advances","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with purified components, cryo-EM structure, multiple biochemical assays in single rigorous study","pmids":["34652950"],"is_preprint":false},{"year":2016,"finding":"SMARCAD1 acts as an ATP-dependent stimulator of CBP-mediated H2A acetylation (K5 and K8) on nucleosomes; SMARCAD1 enhances CBP acetyltransferase activity in an ATP-dependent manner and activates transcription of target genes using native chromatin templates. Drosophila genetic experiments show functional interaction between SMARCAD1/Etl1 and CBP/nej during development.","method":"Column purification of activity from Drosophila nuclear extracts, in vitro H2A acetylation assay, knockdown expression arrays, ChIP-seq, in vitro transcription on native chromatin, Drosophila genetics","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution of acetyltransferase stimulation activity, ChIP-seq, in vitro transcription, genetic interaction, multiple orthogonal methods single lab","pmids":["26888216"],"is_preprint":false},{"year":2008,"finding":"Endogenous SMARCAD1 binds TRIM28 (KAP1) as detected by protein co-immunoprecipitation, and chromatin immunoprecipitation with tiling microarrays shows SMARCAD1 binding near transcriptional start sites of 69 candidate target genes.","method":"Co-immunoprecipitation with specific antibody, ChIP with genome tiling microarray","journal":"Journal of molecular biology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — endogenous Co-IP plus ChIP-chip, single lab, two orthogonal methods","pmids":["18675275"],"is_preprint":false},{"year":2011,"finding":"A heterozygous splice-site mutation in a skin-specific short isoform of SMARCAD1 (disrupting exon donor site) causes autosomal-dominant adermatoglyphia by decreasing stability of the short skin-specific RNA isoform, as demonstrated by minigene splicing assay.","method":"Linkage analysis, Sanger sequencing, minigene splicing assay, RT-PCR stability analysis","journal":"American journal of human genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — minigene functional validation of splice defect plus family segregation, single lab","pmids":["21820097"],"is_preprint":false},{"year":2023,"finding":"MSH2-MSH3 mismatch repair complex is recruited to DSB sites through direct interaction with SMARCAD1; this complex then facilitates EXO1 recruitment and enhances EXO1 enzymatic activity for long-range end resection, while also blocking POLθ access to DSBs to prevent TMEJ.","method":"Co-immunoprecipitation, in vitro EXO1 activity assay, DSB recruitment assays, HR vs TMEJ reporter assays, knockdown epistasis","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, in vitro enzymatic assay, pathway epistasis, single lab with multiple orthogonal methods","pmids":["37140056"],"is_preprint":false},{"year":2024,"finding":"Phosphorylation of SMARCAD1 reduces its binding to nucleosomes, DNA, and histones H2A-H2B, and impairs ATP hydrolysis and histone exchange activity, but has only marginal effect on histone H3-H4 binding and nucleosome assembly. The flexible N-terminal region of SMARCAD1 is critical for nucleosome assembly and histone exchange.","method":"Mutational analysis of phosphorylation sites, in vitro activity assays (ATPase, histone exchange, nucleosome assembly), mass spectrometry, nucleosome binding assays","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro biochemical assays with mutational analysis and mass spectrometry, single lab","pmids":["39424143"],"is_preprint":false},{"year":2023,"finding":"SMARCAD1 interacts directly with TFIIIC (RNA polymerase III general transcription factor) in mouse and human cells; this interaction is conserved across somatic and pluripotent cell types. SMARCAD1 also associates with cohesin, laminB, and DDX5 in mammalian cells.","method":"Endogenous co-immunoprecipitation in multiple cell types, purified-protein direct interaction assay, gene expression analysis","journal":"Genes","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — endogenous Co-IP plus purified-protein direct binding, conservation across cell types, single lab","pmids":["37761933"],"is_preprint":false},{"year":2025,"finding":"SMARCAD1 exhibits substrate preference for subnucleosomal hexasomes over canonical nucleosomes; cryo-EM structures show SMARCAD1 binds hexasome through family-specific elements required for function in vitro and in cells, and binds the canonical nucleosome in an inactive conformation. The FACT complex acts synergistically with H2A-H2B to promote SMARCAD1 remodeling activity on nucleosomes.","method":"Cryo-EM structure determination of SMARCAD1-hexasome and SMARCAD1-nucleosome complexes, in vitro remodeling assays, mutagenesis of family-specific elements, FACT complex co-activity assays, cell-based functional assays","journal":"Nature","confidence":"High","confidence_rationale":"Tier 1 / Strong — high-resolution cryo-EM structures with functional mutagenesis validation and in vitro reconstitution, multiple orthogonal methods","pmids":["40468067"],"is_preprint":false},{"year":2025,"finding":"SMARCAD1 associates with TOPBP1 and both localize to H3K9me3 heterochromatin in mouse ESCs; SMARCAD1 nuclear localization is lost in 2C-like cells, and depletion of SMARCAD1 or TOPBP1 in mouse embryos leads to developmental arrest, reduction of H3K9me3, and remodeling of heterochromatin foci.","method":"Chromatome profiling (chromatin-bound proteome), live-cell imaging of nuclear localization in ESCs vs 2C-like cells, SMARCAD1/TOPBP1 depletion in mouse embryos, H3K9me3 ChIP/immunostaining","journal":"eLife","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — chromatome profiling, live imaging, in vivo embryo depletion with defined phenotypes, single lab","pmids":["39969508"],"is_preprint":false},{"year":2020,"finding":"Fun30 (yeast SMARCAD1 ortholog) is enriched in gene bodies of intron-containing genes, and its depletion impairs pre-mRNA splicing efficiency and spliceosome recruitment in a manner dependent on Fun30's chromatin remodeling activity. The mammalian homolog SMARCAD1 was shown to regulate alternative splicing.","method":"RNA-seq splicing analysis in Fun30-depleted yeast, ChIP of Fun30 at intron-containing genes, spliceosome recruitment assay, ATPase mutant analysis, mammalian alternative splicing analysis","journal":"Biochemical and biophysical research communications","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, limited mechanistic detail in abstract for mammalian SMARCAD1, primarily yeast data","pmids":["32234239"],"is_preprint":false},{"year":2024,"finding":"On broken replication forks (single-ended DSBs), SMARCAD1 displaces 53BP1 to facilitate localization of ubiquitinated PCNA and PIF1 to DSBs for break-induced replication (BIR) activation.","method":"Genetic epistasis, foci analysis, BIR reporter assay, KO cell lines","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 3 / Weak — preprint, single lab, mechanism described but limited biochemical detail in abstract","pmids":["bio_10.1101_2024.09.11.612483"],"is_preprint":true},{"year":2024,"finding":"SMARCAD1 directly binds R-loops via its ATPase domain and associates with the replisome through its N-terminus; both interactions are required for resolving R-loops at active replication forks. SMARCAD1 mutant cells accumulate excess R-loops genome-wide, particularly at regions that overlap with cancer mutation hotspots in germline tumors.","method":"In vitro R-loop binding assay, replisome co-immunoprecipitation, ATPase-domain and N-terminus mutant analysis, genome-wide R-loop mapping (DRIP-seq), mutagenesis analysis in cancer data","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro R-loop binding plus domain mutants plus genome-wide assay, preprint status lowers confidence","pmids":["bio_10.1101_2024.09.13.612941"],"is_preprint":true},{"year":2025,"finding":"In yeast, Fun30 (SMARCAD1 ortholog) displaces the checkpoint mediator Rad9 at replication stress sites together with Slx4, locally dampening S-phase checkpoint signaling; this allows Exo1-dependent resection of stalled forks and homologous recombination factor access for fork stabilization.","method":"Locus-specific ChIP at CPT-stalled forks, genetic epistasis (Fun30/Slx4/Exo1 mutants), checkpoint signaling assays, DNA fiber analysis","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — locus-specific ChIP epistasis plus genetic analysis, yeast ortholog, single lab","pmids":["41978269"],"is_preprint":false},{"year":2025,"finding":"SMARCAD1 depletion in Xenopus egg extract impairs retention of single-strand breaks generated during futile MMR cycling on O6-methylguanine-containing chromatin, establishing Smarcad1 as a chromatin remodeler that facilitates MMR activity in the chromatin context during replication across meG lesions.","method":"Xenopus egg extract reconstitution of MMR on replication-competent chromatin, Smarcad1 immunodepletion, single-strand break retention assay","journal":"Journal of biochemistry","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution in Xenopus extracts with immunodepletion, single lab","pmids":["39882945"],"is_preprint":false},{"year":2025,"finding":"SMARCA4 binds the transcriptional regulatory region of SMARCAD1 and acts as a transcriptional suppressor of SMARCAD1; under replication stress, SMARCA4 binding to the SMARCAD1 locus decreases, leading to upregulation of SMARCAD1, which then accumulates at stalled replication forks.","method":"ChIP assay at SMARCAD1 regulatory region, quantitative RT-PCR, immunofluorescence at stalled forks, clonogenic assays in NSCLC cell lines","journal":"Fujita medical journal","confidence":"Low","confidence_rationale":"Tier 3 / Weak — ChIP and expression data from single lab, limited mechanistic depth about SMARCAD1's own activity","pmids":["41641123"],"is_preprint":false},{"year":2024,"finding":"SMARCAD1 is recruited to MLV provirus immediately after integration in mouse ESCs; Smarcad1 is critical for establishment and maintenance of MLV repression, stabilizes Trim28 binding to the provirus over time, and its presence is required for proper deposition of histone variant H3.3 on the provirus. Combined depletion of Smarcad1 and Trim28 causes enhanced derepression, suggesting partially independent mechanisms.","method":"MLV-GFP reporter repression assay, ChIP at provirus for Trim28 and H3.3, Smarcad1/Trim28 single and double knockdown","journal":"Mobile DNA","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP plus functional reporter assay plus double KD epistasis, single lab, multiple orthogonal approaches","pmids":["38468276"],"is_preprint":false}],"current_model":"SMARCAD1 is an ATP-dependent SWI/SNF-family chromatin remodeler that acts at DNA double-strand breaks to promote 5'-to-3' end resection (via Exo1/Sgs1-dependent pathways) through its ATPase-dependent nucleosome remodeling, is recruited to DSBs via ATM-mediated phosphorylation at T906 (enabling RING1-mediated ubiquitination at K905), stabilizes active replication forks by evicting 53BP1-associated nucleosomes to prevent premature PCNA unloading by ATAD5, maintains heterochromatin after replication by interacting with PCNA, KAP1/TRIM28, HDAC1/2, and G9a/GLP to promote H3K9 methylation, facilitates mismatch repair on chromatin by enabling nucleosome exclusion at mismatches (Msh2-dependent) and MutLα recruitment to chromatin-bound MutSα, and biochemically can perform ATP-dependent histone octamer exchange, de novo nucleosome assembly, and CBP-stimulated H2A acetylation—with substrate preference for hexasomes over canonical nucleosomes as revealed by cryo-EM, while its CUE1 domain mediates direct interaction with KAP1 for nuclear retention and genomic targeting."},"narrative":{"mechanistic_narrative":"SMARCAD1 is an ATP-dependent SWI/SNF-family chromatin remodeler that uses nucleosome mobilization to coordinate DNA double-strand break repair, replication fork integrity, mismatch repair, and heterochromatin maintenance [PMID:22960744, PMID:21549307, PMID:34652950]. Biochemically it can transfer entire histone octamers between DNA segments, assemble nucleosomes de novo by simultaneously engaging all four histones, and stimulate CBP-mediated H2A acetylation in an ATP-dependent manner, with a strong substrate preference for subnucleosomal hexasomes over canonical nucleosomes that is structurally explained by family-specific elements engaging the hexasome and an inactive binding mode on the full nucleosome [PMID:34652950, PMID:26888216, PMID:40468067]. At DNA breaks SMARCAD1 promotes Exo1- and Sgs1-dependent 5'-to-3' end resection through its ATPase activity, channeling repair toward homologous recombination [PMID:22960744]; recruitment to breaks depends on ATM phosphorylation at T906, which licenses RING1-mediated ubiquitination at K905 [PMID:29888761], and is reinforced by direct interaction with the MSH2-MSH3 complex that enhances EXO1 activity while blocking POLθ-dependent end joining [PMID:37140056]. At replication forks SMARCAD1 prevents accumulation of 53BP1-associated nucleosomes, thereby blocking 53BP1/ATAD5-mediated premature PCNA unloading and stabilizing active forks [PMID:33952518]. In heterochromatin, its ATPase activity drives histone H3/H4 deacetylation and H3K9 methylation in concert with KAP1/TRIM28, HDAC1/2, and G9a/GLP, with the CUE1 domain binding the KAP1 RBCC domain to mediate nuclear retention and genomic targeting [PMID:21549307, PMID:29284678]. SMARCAD1 also facilitates mismatch repair in a chromatin context by enabling nucleosome exclusion at mismatches and recruitment of MutLα to chromatin-bound MutSα [PMID:29899141, PMID:31843968]. A splice-site mutation in a skin-specific short isoform of SMARCAD1 causes autosomal-dominant adermatoglyphia [PMID:21820097].","teleology":[{"year":2008,"claim":"Established the first physical and chromatin-binding context for SMARCAD1, linking it to the corepressor KAP1/TRIM28 and to promoter-proximal genomic sites.","evidence":"Endogenous Co-IP and ChIP with tiling microarrays in human cells","pmids":["18675275"],"confidence":"Medium","gaps":["No remodeling activity demonstrated","Functional consequence of TRIM28 binding undefined"]},{"year":2011,"claim":"Defined SMARCAD1 as an ATPase-dependent driver of histone deacetylation and H3K9 methylation that couples heterochromatin maintenance to replication via PCNA.","evidence":"ATPase mutant complementation, Co-IP with KAP1/HDAC1-2/G9a-GLP, histone-mark ChIP, replication-foci imaging","pmids":["21549307"],"confidence":"High","gaps":["Direct enzymatic remodeling step not reconstituted in vitro","Order of deacetylation vs methylation events unresolved"]},{"year":2011,"claim":"Connected SMARCAD1 to a human Mendelian phenotype, showing a skin-specific isoform splice defect underlies adermatoglyphia.","evidence":"Linkage, Sanger sequencing, minigene splicing assay, RT-PCR stability","pmids":["21820097"],"confidence":"Medium","gaps":["Mechanism linking isoform loss to dermatoglyph development unknown","Single-family/locus depth"]},{"year":2012,"claim":"Placed SMARCAD1/Fun30 directly in DSB end resection, identifying it as an ATPase-dependent promoter of Exo1/Sgs1 pathways feeding homologous recombination.","evidence":"ChIP at DSBs, ATPase-dead mutants, epistasis with Exo1/Sgs1, drug-sensitivity assays in yeast and human cells","pmids":["22960744"],"confidence":"High","gaps":["Nucleosome substrate at the break not structurally defined","Recruitment signal to DSBs not identified"]},{"year":2016,"claim":"Showed SMARCAD1 acts as a positive cofactor for histone acetylation/transcription, broadening its activity beyond repression.","evidence":"Activity purification from Drosophila extracts, in vitro H2A acetylation and transcription assays, ChIP-seq, fly genetics","pmids":["26888216"],"confidence":"High","gaps":["Mechanism by which ATPase stimulates CBP unclear","Mammalian generality of transcriptional activation not established"]},{"year":2017,"claim":"Mapped the CUE1 domain to KAP1 RBCC binding, explaining how SMARCAD1 achieves nuclear retention and targeting to imprinted/ZFP loci.","evidence":"Endogenous Co-IP, purified-protein binding, domain mutants, ChIP, nuclear fractionation","pmids":["29284678"],"confidence":"High","gaps":["Whether KAP1 binding regulates remodeling activity untested","Targeting at non-KAP1 loci unexplained"]},{"year":2017,"claim":"Linked SMARCAD1 to a histone-mark reader function (H3R26 citrullination) that restrains H3K9me3 and supports naive pluripotency.","evidence":"Histone peptide array, ChIP-seq, knockdown, embryoid body/chimera assays","pmids":["28355564"],"confidence":"Medium","gaps":["Direct binding domain for H3R26Cit not mapped","Relationship to its heterochromatin-promoting role unresolved"]},{"year":2018,"claim":"Identified the ATM-T906 phosphorylation/RING1-K905 ubiquitination switch governing SMARCAD1 recruitment to breaks for resection and HR.","evidence":"T906/K905 mutagenesis, phospho-specific antibodies, IR-foci and HR reporter assays","pmids":["29888761"],"confidence":"Medium","gaps":["RING1 E3 specificity not validated reciprocally","Single-lab data"]},{"year":2018,"claim":"Extended SMARCAD1 function to mismatch repair, showing Msh2-dependent recruitment and nucleosome exclusion around mismatches.","evidence":"Xenopus extract chromatin assembly/disassembly, immunodepletion, yeast genetic epistasis with MSH6/MSH3","pmids":["29899141"],"confidence":"High","gaps":["Whether remodeling precedes or follows MutSα binding unclear","Direct MSH2 contact not mapped"]},{"year":2019,"claim":"Showed SMARCAD1 ATPase activity is needed for MutLα recruitment to chromatin-bound MutSα, coupling remodeling to MMR signaling and apoptosis.","evidence":"KO and ATPase-mutant rescue, chromatin-fraction Co-IP after MNU, sub-G1/caspase readouts","pmids":["31843968"],"confidence":"Medium","gaps":["Direct vs indirect effect on MutLα loading unresolved","Single-lab"]},{"year":2021,"claim":"Defined a replication-fork protection role: SMARCAD1 evicts 53BP1-associated nucleosomes to prevent ATAD5-driven premature PCNA unloading.","evidence":"KO/KD, 53BP1/BRCA1/ATAD5 epistasis, DNA fiber, iPOND, rescue experiments","pmids":["33952518"],"confidence":"High","gaps":["Structural basis of 53BP1-nucleosome eviction not defined","How SMARCAD1 distinguishes fork nucleosomes unknown"]},{"year":2021,"claim":"Provided the biochemical/structural foundation: SMARCAD1 performs ATP-dependent octamer exchange and de novo assembly, binding all four histones, with an atypical ATPase-nucleosome engagement.","evidence":"In vitro histone exchange/assembly assays and cryo-EM of purified components","pmids":["34652950"],"confidence":"High","gaps":["In vivo substrate that requires octamer transfer not pinpointed","Regulation of assembly vs eviction modes unclear"]},{"year":2023,"claim":"Identified MSH2-MSH3 as a direct DSB partner that, with SMARCAD1, enhances EXO1 resection and suppresses POLθ/TMEJ.","evidence":"Co-IP, in vitro EXO1 activity assays, recruitment and HR/TMEJ reporters, knockdown epistasis","pmids":["37140056"],"confidence":"Medium","gaps":["Stoichiometry/order of SMARCAD1-MSH2/3-EXO1 assembly unresolved","Single-lab"]},{"year":2023,"claim":"Expanded the SMARCAD1 interactome to TFIIIC, cohesin, laminB and DDX5, implicating it in higher-order chromatin organization and Pol III contexts.","evidence":"Endogenous Co-IP across cell types plus purified-protein direct binding","pmids":["37761933"],"confidence":"Medium","gaps":["Functional consequence of TFIIIC interaction untested","Whether interactions are simultaneous or distinct complexes unknown"]},{"year":2024,"claim":"Showed phosphorylation tunes SMARCAD1 activity by weakening nucleosome/DNA/H2A-H2B binding and ATP hydrolysis, and identified the N-terminus as critical for assembly/exchange.","evidence":"In vitro ATPase/exchange/assembly assays with phospho-site mutants and mass spectrometry","pmids":["39424143"],"confidence":"Medium","gaps":["Responsible kinase(s) in this context not defined","In vivo relevance of these phospho-sites untested"]},{"year":2024,"claim":"Implicated SMARCAD1 in proviral silencing, showing it stabilizes Trim28 binding and H3.3 deposition to repress MLV in ESCs.","evidence":"MLV-GFP reporter, ChIP for Trim28/H3.3, single and double knockdown","pmids":["38468276"],"confidence":"Medium","gaps":["Mechanism of H3.3 deposition support unclear","Trim28-independent component undefined"]},{"year":2024,"claim":"Proposed SMARCAD1 as an R-loop-resolving factor at replication forks, binding R-loops via its ATPase domain and the replisome via its N-terminus (preprint).","evidence":"In vitro R-loop binding, replisome Co-IP, domain mutants, DRIP-seq (preprint)","pmids":["bio_10.1101_2024.09.13.612941"],"confidence":"Medium","gaps":["Preprint, not peer-reviewed","Direct enzymatic R-loop resolution vs displacement not distinguished"]},{"year":2025,"claim":"Resolved the structural basis of substrate selectivity, showing SMARCAD1 prefers hexasomes over canonical nucleosomes and is co-activated by FACT plus H2A-H2B.","evidence":"Cryo-EM of SMARCAD1-hexasome and -nucleosome complexes, remodeling assays, mutagenesis of family-specific elements, FACT co-activity","pmids":["40468067"],"confidence":"High","gaps":["When hexasome substrates arise in vivo not defined","Link between hexasome preference and specific repair pathways unclear"]},{"year":2025,"claim":"Tied SMARCAD1 to embryonic heterochromatin via TOPBP1 partnership, with depletion causing H3K9me3 loss and developmental arrest.","evidence":"Chromatome profiling, live-cell imaging in ESC vs 2C-like cells, embryo depletion, H3K9me3 ChIP/immunostaining","pmids":["39969508"],"confidence":"Medium","gaps":["Direct vs indirect TOPBP1 contact not mapped","Mechanism of nuclear export in 2C-like state unknown"]},{"year":2025,"claim":"Reconstituted SMARCAD1's role in chromatin-context MMR across O6-methylguanine lesions, showing it sustains single-strand break retention during futile MMR cycling.","evidence":"Xenopus egg extract MMR reconstitution with Smarcad1 immunodepletion","pmids":["39882945"],"confidence":"Medium","gaps":["Molecular step of SSB retention unclear","Mammalian cell confirmation lacking"]},{"year":2025,"claim":"Showed the yeast ortholog Fun30 dampens checkpoint signaling by displacing Rad9 with Slx4, enabling Exo1 resection and fork stabilization.","evidence":"Locus-specific ChIP at CPT-stalled forks, Fun30/Slx4/Exo1 epistasis, checkpoint and fiber assays","pmids":["41978269"],"confidence":"Medium","gaps":["Conservation of Rad9/53BP1 displacement mechanism to human SMARCAD1 untested at this locus","Yeast ortholog data"]},{"year":null,"claim":"How SMARCAD1's distinct activities (resection, fork protection, MMR, heterochromatin assembly, transcriptional activation) are selectively deployed at the right substrate and locus remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking hexasome preference and phospho-regulation to pathway choice","In vivo upstream signals that partition functions undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[0,1,8,15]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[8,9,15]},{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[3,8]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[19]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[8,13]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[4,16]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[0,7]},{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[1,5,6]}],"pathway":[{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[0,2,12]},{"term_id":"R-HSA-69306","term_label":"DNA Replication","supporting_discovery_ids":[1,7]},{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[1,4,16]}],"complexes":[],"partners":["TRIM28","PCNA","HDAC1","MSH2","MSH6","MLH1","TFIIIC","TOPBP1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9H4L7","full_name":"SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A containing DEAD/H box 1","aliases":[],"length_aa":1026,"mass_kda":117.4,"function":"Protein that possesses intrinsic ATP-dependent nucleosome-remodeling activity and is both required for DNA repair and heterochromatin organization (PubMed:22960744, PubMed:21820097). Combines the ATP-dependent ability to exchange histones, with the chaperone-like ATP-independent activity to deposit histones and assemble nucleosomes (PubMed:21820097). Promotes DNA end resection of double-strand breaks (DSBs) following DNA damage: probably acts by weakening histone DNA interactions in nucleosomes flanking DSBs (PubMed:22960744). Required for the restoration of heterochromatin organization after replication (PubMed:21549307). Acts at replication sites to facilitate the maintenance of heterochromatin by directing H3 and H4 histones deacetylation, H3 'Lys-9' trimethylation (H3K9me3) and restoration of silencing (PubMed:21549307)","subcellular_location":"Nucleus; Chromosome","url":"https://www.uniprot.org/uniprotkb/Q9H4L7/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/SMARCAD1","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1208,"dependency_fraction":0.0008278145695364238},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000163104","cell_line_id":"CID001674","localizations":[{"compartment":"nucleoplasm","grade":3},{"compartment":"chromatin","grade":2}],"interactors":[{"gene":"MSH6","stoichiometry":0.2},{"gene":"TRIM28","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID001674","total_profiled":1310},"omim":[{"mim_id":"612761","title":"SWI/SNF-RELATED, MATRIX-ASSOCIATED ACTIN-DEPENDENT REGULATOR OF CHROMATIN, SUBFAMILY A, DEAD/H BOX-CONTAINING, 1; SMARCAD1","url":"https://www.omim.org/entry/612761"},{"mim_id":"181600","title":"HURIEZ SYNDROME; HRZ","url":"https://www.omim.org/entry/181600"},{"mim_id":"136000","title":"ADERMATOGLYPHIA; ADERM","url":"https://www.omim.org/entry/136000"},{"mim_id":"129200","title":"BASAN SYNDROME","url":"https://www.omim.org/entry/129200"},{"mim_id":"125590","title":"DERMATOGLYPHICS--FINGERPRINT PATTERN","url":"https://www.omim.org/entry/125590"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Enhanced","locations":[{"location":"Nucleoplasm","reliability":"Enhanced"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/SMARCAD1"},"hgnc":{"alias_symbol":["ETL1","DKFZP762K2015","KIAA1122","DKFZp762K2015"],"prev_symbol":["HPGDS-AS1"]},"alphafold":{"accession":"Q9H4L7","domains":[{"cath_id":"-","chopping":"386-454","consensus_level":"high","plddt":77.2725,"start":386,"end":454},{"cath_id":"3.40.50.10810","chopping":"484-728","consensus_level":"high","plddt":80.3118,"start":484,"end":728},{"cath_id":"3.40.50.300","chopping":"735-744_852-1025","consensus_level":"high","plddt":83.4452,"start":735,"end":1025},{"cath_id":"-","chopping":"793-845","consensus_level":"medium","plddt":87.7687,"start":793,"end":845}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9H4L7","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9H4L7-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9H4L7-F1-predicted_aligned_error_v6.png","plddt_mean":67.06},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=SMARCAD1","jax_strain_url":"https://www.jax.org/strain/search?query=SMARCAD1"},"sequence":{"accession":"Q9H4L7","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9H4L7.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9H4L7/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9H4L7"}},"corpus_meta":[{"pmid":"22960744","id":"PMC_22960744","title":"The 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genomics","url":"https://pubmed.ncbi.nlm.nih.gov/37165199","citation_count":3,"is_preprint":false},{"pmid":"39424143","id":"PMC_39424143","title":"Phosphorylation regulates the chromatin remodeler SMARCAD1 in nucleosome binding, ATP hydrolysis, and histone exchange.","date":"2024","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/39424143","citation_count":2,"is_preprint":false},{"pmid":"39969508","id":"PMC_39969508","title":"SMARCAD1 and TOPBP1 contribute to heterochromatin maintenance at the transition from the 2C-like to the pluripotent state.","date":"2025","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/39969508","citation_count":2,"is_preprint":false},{"pmid":"32234239","id":"PMC_32234239","title":"Role of the ATP-dependent chromatin remodeling enzyme Fun30/Smarcad1 in the regulation of mRNA splicing.","date":"2020","source":"Biochemical and biophysical research 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mutant analysis, epistasis with Exo1/Sgs1, camptothecin/PARP inhibitor sensitivity assays\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal genetic and biochemical analysis in both yeast and human cells, ATPase mutant validation, multiple orthogonal methods, replicated across organisms\",\n      \"pmids\": [\"22960744\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"SMARCAD1's ATPase activity is required for global deacetylation of histones H3/H4, which promotes H3K9 methylation and heterochromatin establishment; SMARCAD1 associates with KAP1, HDAC1/2, and G9a/GLP, modulates HDAC1-KAP1 interaction at heterochromatin, and directly interacts with PCNA to be recruited to replication sites.\",\n      \"method\": \"ATPase mutant complementation, Co-immunoprecipitation, histone modification ChIP, live-cell imaging at replication foci, chromosome segregation assay\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (Co-IP, ChIP, ATPase mutant, PCNA interaction), direct interaction with replication machinery demonstrated\",\n      \"pmids\": [\"21549307\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"ATM kinase phosphorylates SMARCAD1 at T906 in response to ionizing radiation; this phosphorylation is required for SMARCAD1 recruitment to DSBs, and T906 phosphorylation also enables subsequent ubiquitination of SMARCAD1 at K905 by RING1. Both PTMs are required for SMARCAD1's role in DNA end resection and HR-mediated repair.\",\n      \"method\": \"Site-directed mutagenesis of T906 and K905, phospho-specific antibodies, Co-immunoprecipitation, IR-induced foci assays, HR reporter assay\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis plus functional assays in single lab, two orthogonal PTM modifications demonstrated\",\n      \"pmids\": [\"29888761\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"SMARCAD1 preferentially binds H3R26-citrullinated histone peptides and co-localizes genome-wide with H3R26Cit; SMARCAD1 occupancy at H3R26Cit sites suppresses H3K9me3 accumulation, and its knockdown increases H3K9me3 at those loci, linking it to maintenance of naive pluripotency.\",\n      \"method\": \"Histone peptide array binding (384 modifications), ChIP-seq, Smarcad1 knockdown, gene expression analysis, embryoid body and chimera assays\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — histone peptide array plus ChIP-seq and KD phenotype, single lab, multiple orthogonal approaches\",\n      \"pmids\": [\"28355564\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"The CUE1 domain of SMARCAD1 directly mediates binding to the RBCC domain of KAP1 (TRIM28); this interaction occurs on chromatin and is required for SMARCAD1 nuclear retention and its association with KAP1 target genes including ZFP and imprinted genes.\",\n      \"method\": \"Co-immunoprecipitation of endogenous proteins, CUE1 domain mutations in vitro and in vivo, ChIP, nuclear fractionation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct interaction confirmed by in vitro binding with purified proteins plus in vivo Co-IP, domain-mapping mutations, ChIP validation, multiple orthogonal methods\",\n      \"pmids\": [\"29284678\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"In Xenopus egg extracts, Smarcad1 is recruited to mismatch-containing DNA in an Msh2-dependent but Mlh1-independent manner, and facilitates nucleosome exclusion around mismatches; it assists mismatch repair when nucleosomes are preassembled on DNA. In yeast, Fun30 deletion combined with MSH6 or MSH3 deletion synergistically increases spontaneous mutations.\",\n      \"method\": \"Xenopus egg extract chromatin assembly/disassembly assay, immunodepletion, genetic epistasis in yeast (double mutants), nucleosome occupancy assays\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — reconstitution in Xenopus extracts plus yeast genetic epistasis, multiple orthogonal approaches, mechanistic pathway placement\",\n      \"pmids\": [\"29899141\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"SMARCAD1 ATPase activity is required for recruitment of MutLα (MLH1-PMS2) to chromatin-bound MutSα (MSH2-MSH6) after alkylating-agent-induced DNA damage; loss of SMARCAD1 impairs this recruitment, suppresses apoptosis, and increases mutation frequency.\",\n      \"method\": \"SMARCAD1 knockout cells, MNU treatment, co-immunoprecipitation of MutSα and MutLα from chromatin fractions, ATPase-dead mutant complementation, sub-G1/caspase assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO plus ATPase mutant rescue, Co-IP from chromatin fractions, single lab with multiple functional readouts\",\n      \"pmids\": [\"31843968\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"SMARCAD1 stabilizes active replication forks by preventing accumulation of 53BP1-associated nucleosomes at forks; in SMARCAD1-deficient cells, 53BP1 mediates premature PCNA removal via the PCNA-unloader ATAD5, causing fork stalling and ssDNA accumulation. Loss of 53BP1 rescues these defects but requires BRCA1-mediated fork protection.\",\n      \"method\": \"SMARCAD1 KO/knockdown, 53BP1 co-depletion epistasis, DNA fiber assays, PCNA/ATAD5 interaction studies, iPOND, genetic rescue experiments\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis (SMARCAD1/53BP1/BRCA1/ATAD5), DNA fiber assay, iPOND, multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"33952518\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"SMARCAD1 can transfer an entire histone octamer from one DNA segment to another in an ATP-dependent manner (histone octamer exchange), and can also perform de novo nucleosome assembly from histone octamer due to its ability to simultaneously bind all four histones. Cryo-EM reveals that the ATPase domains engage the nucleosome differently from other chromatin remodelers.\",\n      \"method\": \"In vitro histone exchange assay, de novo nucleosome assembly assay, cryo-EM structure determination, biochemical binding assays\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with purified components, cryo-EM structure, multiple biochemical assays in single rigorous study\",\n      \"pmids\": [\"34652950\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"SMARCAD1 acts as an ATP-dependent stimulator of CBP-mediated H2A acetylation (K5 and K8) on nucleosomes; SMARCAD1 enhances CBP acetyltransferase activity in an ATP-dependent manner and activates transcription of target genes using native chromatin templates. Drosophila genetic experiments show functional interaction between SMARCAD1/Etl1 and CBP/nej during development.\",\n      \"method\": \"Column purification of activity from Drosophila nuclear extracts, in vitro H2A acetylation assay, knockdown expression arrays, ChIP-seq, in vitro transcription on native chromatin, Drosophila genetics\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution of acetyltransferase stimulation activity, ChIP-seq, in vitro transcription, genetic interaction, multiple orthogonal methods single lab\",\n      \"pmids\": [\"26888216\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Endogenous SMARCAD1 binds TRIM28 (KAP1) as detected by protein co-immunoprecipitation, and chromatin immunoprecipitation with tiling microarrays shows SMARCAD1 binding near transcriptional start sites of 69 candidate target genes.\",\n      \"method\": \"Co-immunoprecipitation with specific antibody, ChIP with genome tiling microarray\",\n      \"journal\": \"Journal of molecular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — endogenous Co-IP plus ChIP-chip, single lab, two orthogonal methods\",\n      \"pmids\": [\"18675275\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"A heterozygous splice-site mutation in a skin-specific short isoform of SMARCAD1 (disrupting exon donor site) causes autosomal-dominant adermatoglyphia by decreasing stability of the short skin-specific RNA isoform, as demonstrated by minigene splicing assay.\",\n      \"method\": \"Linkage analysis, Sanger sequencing, minigene splicing assay, RT-PCR stability analysis\",\n      \"journal\": \"American journal of human genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — minigene functional validation of splice defect plus family segregation, single lab\",\n      \"pmids\": [\"21820097\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MSH2-MSH3 mismatch repair complex is recruited to DSB sites through direct interaction with SMARCAD1; this complex then facilitates EXO1 recruitment and enhances EXO1 enzymatic activity for long-range end resection, while also blocking POLθ access to DSBs to prevent TMEJ.\",\n      \"method\": \"Co-immunoprecipitation, in vitro EXO1 activity assay, DSB recruitment assays, HR vs TMEJ reporter assays, knockdown epistasis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, in vitro enzymatic assay, pathway epistasis, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"37140056\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Phosphorylation of SMARCAD1 reduces its binding to nucleosomes, DNA, and histones H2A-H2B, and impairs ATP hydrolysis and histone exchange activity, but has only marginal effect on histone H3-H4 binding and nucleosome assembly. The flexible N-terminal region of SMARCAD1 is critical for nucleosome assembly and histone exchange.\",\n      \"method\": \"Mutational analysis of phosphorylation sites, in vitro activity assays (ATPase, histone exchange, nucleosome assembly), mass spectrometry, nucleosome binding assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro biochemical assays with mutational analysis and mass spectrometry, single lab\",\n      \"pmids\": [\"39424143\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"SMARCAD1 interacts directly with TFIIIC (RNA polymerase III general transcription factor) in mouse and human cells; this interaction is conserved across somatic and pluripotent cell types. SMARCAD1 also associates with cohesin, laminB, and DDX5 in mammalian cells.\",\n      \"method\": \"Endogenous co-immunoprecipitation in multiple cell types, purified-protein direct interaction assay, gene expression analysis\",\n      \"journal\": \"Genes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — endogenous Co-IP plus purified-protein direct binding, conservation across cell types, single lab\",\n      \"pmids\": [\"37761933\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"SMARCAD1 exhibits substrate preference for subnucleosomal hexasomes over canonical nucleosomes; cryo-EM structures show SMARCAD1 binds hexasome through family-specific elements required for function in vitro and in cells, and binds the canonical nucleosome in an inactive conformation. The FACT complex acts synergistically with H2A-H2B to promote SMARCAD1 remodeling activity on nucleosomes.\",\n      \"method\": \"Cryo-EM structure determination of SMARCAD1-hexasome and SMARCAD1-nucleosome complexes, in vitro remodeling assays, mutagenesis of family-specific elements, FACT complex co-activity assays, cell-based functional assays\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — high-resolution cryo-EM structures with functional mutagenesis validation and in vitro reconstitution, multiple orthogonal methods\",\n      \"pmids\": [\"40468067\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"SMARCAD1 associates with TOPBP1 and both localize to H3K9me3 heterochromatin in mouse ESCs; SMARCAD1 nuclear localization is lost in 2C-like cells, and depletion of SMARCAD1 or TOPBP1 in mouse embryos leads to developmental arrest, reduction of H3K9me3, and remodeling of heterochromatin foci.\",\n      \"method\": \"Chromatome profiling (chromatin-bound proteome), live-cell imaging of nuclear localization in ESCs vs 2C-like cells, SMARCAD1/TOPBP1 depletion in mouse embryos, H3K9me3 ChIP/immunostaining\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — chromatome profiling, live imaging, in vivo embryo depletion with defined phenotypes, single lab\",\n      \"pmids\": [\"39969508\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Fun30 (yeast SMARCAD1 ortholog) is enriched in gene bodies of intron-containing genes, and its depletion impairs pre-mRNA splicing efficiency and spliceosome recruitment in a manner dependent on Fun30's chromatin remodeling activity. The mammalian homolog SMARCAD1 was shown to regulate alternative splicing.\",\n      \"method\": \"RNA-seq splicing analysis in Fun30-depleted yeast, ChIP of Fun30 at intron-containing genes, spliceosome recruitment assay, ATPase mutant analysis, mammalian alternative splicing analysis\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, limited mechanistic detail in abstract for mammalian SMARCAD1, primarily yeast data\",\n      \"pmids\": [\"32234239\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"On broken replication forks (single-ended DSBs), SMARCAD1 displaces 53BP1 to facilitate localization of ubiquitinated PCNA and PIF1 to DSBs for break-induced replication (BIR) activation.\",\n      \"method\": \"Genetic epistasis, foci analysis, BIR reporter assay, KO cell lines\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — preprint, single lab, mechanism described but limited biochemical detail in abstract\",\n      \"pmids\": [\"bio_10.1101_2024.09.11.612483\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"SMARCAD1 directly binds R-loops via its ATPase domain and associates with the replisome through its N-terminus; both interactions are required for resolving R-loops at active replication forks. SMARCAD1 mutant cells accumulate excess R-loops genome-wide, particularly at regions that overlap with cancer mutation hotspots in germline tumors.\",\n      \"method\": \"In vitro R-loop binding assay, replisome co-immunoprecipitation, ATPase-domain and N-terminus mutant analysis, genome-wide R-loop mapping (DRIP-seq), mutagenesis analysis in cancer data\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro R-loop binding plus domain mutants plus genome-wide assay, preprint status lowers confidence\",\n      \"pmids\": [\"bio_10.1101_2024.09.13.612941\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In yeast, Fun30 (SMARCAD1 ortholog) displaces the checkpoint mediator Rad9 at replication stress sites together with Slx4, locally dampening S-phase checkpoint signaling; this allows Exo1-dependent resection of stalled forks and homologous recombination factor access for fork stabilization.\",\n      \"method\": \"Locus-specific ChIP at CPT-stalled forks, genetic epistasis (Fun30/Slx4/Exo1 mutants), checkpoint signaling assays, DNA fiber analysis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — locus-specific ChIP epistasis plus genetic analysis, yeast ortholog, single lab\",\n      \"pmids\": [\"41978269\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"SMARCAD1 depletion in Xenopus egg extract impairs retention of single-strand breaks generated during futile MMR cycling on O6-methylguanine-containing chromatin, establishing Smarcad1 as a chromatin remodeler that facilitates MMR activity in the chromatin context during replication across meG lesions.\",\n      \"method\": \"Xenopus egg extract reconstitution of MMR on replication-competent chromatin, Smarcad1 immunodepletion, single-strand break retention assay\",\n      \"journal\": \"Journal of biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution in Xenopus extracts with immunodepletion, single lab\",\n      \"pmids\": [\"39882945\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"SMARCA4 binds the transcriptional regulatory region of SMARCAD1 and acts as a transcriptional suppressor of SMARCAD1; under replication stress, SMARCA4 binding to the SMARCAD1 locus decreases, leading to upregulation of SMARCAD1, which then accumulates at stalled replication forks.\",\n      \"method\": \"ChIP assay at SMARCAD1 regulatory region, quantitative RT-PCR, immunofluorescence at stalled forks, clonogenic assays in NSCLC cell lines\",\n      \"journal\": \"Fujita medical journal\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — ChIP and expression data from single lab, limited mechanistic depth about SMARCAD1's own activity\",\n      \"pmids\": [\"41641123\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"SMARCAD1 is recruited to MLV provirus immediately after integration in mouse ESCs; Smarcad1 is critical for establishment and maintenance of MLV repression, stabilizes Trim28 binding to the provirus over time, and its presence is required for proper deposition of histone variant H3.3 on the provirus. Combined depletion of Smarcad1 and Trim28 causes enhanced derepression, suggesting partially independent mechanisms.\",\n      \"method\": \"MLV-GFP reporter repression assay, ChIP at provirus for Trim28 and H3.3, Smarcad1/Trim28 single and double knockdown\",\n      \"journal\": \"Mobile DNA\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP plus functional reporter assay plus double KD epistasis, single lab, multiple orthogonal approaches\",\n      \"pmids\": [\"38468276\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"SMARCAD1 is an ATP-dependent SWI/SNF-family chromatin remodeler that acts at DNA double-strand breaks to promote 5'-to-3' end resection (via Exo1/Sgs1-dependent pathways) through its ATPase-dependent nucleosome remodeling, is recruited to DSBs via ATM-mediated phosphorylation at T906 (enabling RING1-mediated ubiquitination at K905), stabilizes active replication forks by evicting 53BP1-associated nucleosomes to prevent premature PCNA unloading by ATAD5, maintains heterochromatin after replication by interacting with PCNA, KAP1/TRIM28, HDAC1/2, and G9a/GLP to promote H3K9 methylation, facilitates mismatch repair on chromatin by enabling nucleosome exclusion at mismatches (Msh2-dependent) and MutLα recruitment to chromatin-bound MutSα, and biochemically can perform ATP-dependent histone octamer exchange, de novo nucleosome assembly, and CBP-stimulated H2A acetylation—with substrate preference for hexasomes over canonical nucleosomes as revealed by cryo-EM, while its CUE1 domain mediates direct interaction with KAP1 for nuclear retention and genomic targeting.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"SMARCAD1 is an ATP-dependent SWI/SNF-family chromatin remodeler that uses nucleosome mobilization to coordinate DNA double-strand break repair, replication fork integrity, mismatch repair, and heterochromatin maintenance [#0, #1, #8]. Biochemically it can transfer entire histone octamers between DNA segments, assemble nucleosomes de novo by simultaneously engaging all four histones, and stimulate CBP-mediated H2A acetylation in an ATP-dependent manner, with a strong substrate preference for subnucleosomal hexasomes over canonical nucleosomes that is structurally explained by family-specific elements engaging the hexasome and an inactive binding mode on the full nucleosome [#8, #9, #15]. At DNA breaks SMARCAD1 promotes Exo1- and Sgs1-dependent 5'-to-3' end resection through its ATPase activity, channeling repair toward homologous recombination [#0]; recruitment to breaks depends on ATM phosphorylation at T906, which licenses RING1-mediated ubiquitination at K905 [#2], and is reinforced by direct interaction with the MSH2-MSH3 complex that enhances EXO1 activity while blocking POL\\u03b8-dependent end joining [#12]. At replication forks SMARCAD1 prevents accumulation of 53BP1-associated nucleosomes, thereby blocking 53BP1/ATAD5-mediated premature PCNA unloading and stabilizing active forks [#7]. In heterochromatin, its ATPase activity drives histone H3/H4 deacetylation and H3K9 methylation in concert with KAP1/TRIM28, HDAC1/2, and G9a/GLP, with the CUE1 domain binding the KAP1 RBCC domain to mediate nuclear retention and genomic targeting [#1, #4]. SMARCAD1 also facilitates mismatch repair in a chromatin context by enabling nucleosome exclusion at mismatches and recruitment of MutL\\u03b1 to chromatin-bound MutS\\u03b1 [#5, #6]. A splice-site mutation in a skin-specific short isoform of SMARCAD1 causes autosomal-dominant adermatoglyphia [#11].\",\n  \"teleology\": [\n    {\n      \"year\": 2008,\n      \"claim\": \"Established the first physical and chromatin-binding context for SMARCAD1, linking it to the corepressor KAP1/TRIM28 and to promoter-proximal genomic sites.\",\n      \"evidence\": \"Endogenous Co-IP and ChIP with tiling microarrays in human cells\",\n      \"pmids\": [\"18675275\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No remodeling activity demonstrated\", \"Functional consequence of TRIM28 binding undefined\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Defined SMARCAD1 as an ATPase-dependent driver of histone deacetylation and H3K9 methylation that couples heterochromatin maintenance to replication via PCNA.\",\n      \"evidence\": \"ATPase mutant complementation, Co-IP with KAP1/HDAC1-2/G9a-GLP, histone-mark ChIP, replication-foci imaging\",\n      \"pmids\": [\"21549307\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct enzymatic remodeling step not reconstituted in vitro\", \"Order of deacetylation vs methylation events unresolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Connected SMARCAD1 to a human Mendelian phenotype, showing a skin-specific isoform splice defect underlies adermatoglyphia.\",\n      \"evidence\": \"Linkage, Sanger sequencing, minigene splicing assay, RT-PCR stability\",\n      \"pmids\": [\"21820097\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism linking isoform loss to dermatoglyph development unknown\", \"Single-family/locus depth\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Placed SMARCAD1/Fun30 directly in DSB end resection, identifying it as an ATPase-dependent promoter of Exo1/Sgs1 pathways feeding homologous recombination.\",\n      \"evidence\": \"ChIP at DSBs, ATPase-dead mutants, epistasis with Exo1/Sgs1, drug-sensitivity assays in yeast and human cells\",\n      \"pmids\": [\"22960744\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Nucleosome substrate at the break not structurally defined\", \"Recruitment signal to DSBs not identified\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Showed SMARCAD1 acts as a positive cofactor for histone acetylation/transcription, broadening its activity beyond repression.\",\n      \"evidence\": \"Activity purification from Drosophila extracts, in vitro H2A acetylation and transcription assays, ChIP-seq, fly genetics\",\n      \"pmids\": [\"26888216\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which ATPase stimulates CBP unclear\", \"Mammalian generality of transcriptional activation not established\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Mapped the CUE1 domain to KAP1 RBCC binding, explaining how SMARCAD1 achieves nuclear retention and targeting to imprinted/ZFP loci.\",\n      \"evidence\": \"Endogenous Co-IP, purified-protein binding, domain mutants, ChIP, nuclear fractionation\",\n      \"pmids\": [\"29284678\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether KAP1 binding regulates remodeling activity untested\", \"Targeting at non-KAP1 loci unexplained\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Linked SMARCAD1 to a histone-mark reader function (H3R26 citrullination) that restrains H3K9me3 and supports naive pluripotency.\",\n      \"evidence\": \"Histone peptide array, ChIP-seq, knockdown, embryoid body/chimera assays\",\n      \"pmids\": [\"28355564\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct binding domain for H3R26Cit not mapped\", \"Relationship to its heterochromatin-promoting role unresolved\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Identified the ATM-T906 phosphorylation/RING1-K905 ubiquitination switch governing SMARCAD1 recruitment to breaks for resection and HR.\",\n      \"evidence\": \"T906/K905 mutagenesis, phospho-specific antibodies, IR-foci and HR reporter assays\",\n      \"pmids\": [\"29888761\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"RING1 E3 specificity not validated reciprocally\", \"Single-lab data\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Extended SMARCAD1 function to mismatch repair, showing Msh2-dependent recruitment and nucleosome exclusion around mismatches.\",\n      \"evidence\": \"Xenopus extract chromatin assembly/disassembly, immunodepletion, yeast genetic epistasis with MSH6/MSH3\",\n      \"pmids\": [\"29899141\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether remodeling precedes or follows MutS\\u03b1 binding unclear\", \"Direct MSH2 contact not mapped\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Showed SMARCAD1 ATPase activity is needed for MutL\\u03b1 recruitment to chromatin-bound MutS\\u03b1, coupling remodeling to MMR signaling and apoptosis.\",\n      \"evidence\": \"KO and ATPase-mutant rescue, chromatin-fraction Co-IP after MNU, sub-G1/caspase readouts\",\n      \"pmids\": [\"31843968\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct vs indirect effect on MutL\\u03b1 loading unresolved\", \"Single-lab\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Defined a replication-fork protection role: SMARCAD1 evicts 53BP1-associated nucleosomes to prevent ATAD5-driven premature PCNA unloading.\",\n      \"evidence\": \"KO/KD, 53BP1/BRCA1/ATAD5 epistasis, DNA fiber, iPOND, rescue experiments\",\n      \"pmids\": [\"33952518\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of 53BP1-nucleosome eviction not defined\", \"How SMARCAD1 distinguishes fork nucleosomes unknown\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Provided the biochemical/structural foundation: SMARCAD1 performs ATP-dependent octamer exchange and de novo assembly, binding all four histones, with an atypical ATPase-nucleosome engagement.\",\n      \"evidence\": \"In vitro histone exchange/assembly assays and cryo-EM of purified components\",\n      \"pmids\": [\"34652950\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo substrate that requires octamer transfer not pinpointed\", \"Regulation of assembly vs eviction modes unclear\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identified MSH2-MSH3 as a direct DSB partner that, with SMARCAD1, enhances EXO1 resection and suppresses POL\\u03b8/TMEJ.\",\n      \"evidence\": \"Co-IP, in vitro EXO1 activity assays, recruitment and HR/TMEJ reporters, knockdown epistasis\",\n      \"pmids\": [\"37140056\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Stoichiometry/order of SMARCAD1-MSH2/3-EXO1 assembly unresolved\", \"Single-lab\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Expanded the SMARCAD1 interactome to TFIIIC, cohesin, laminB and DDX5, implicating it in higher-order chromatin organization and Pol III contexts.\",\n      \"evidence\": \"Endogenous Co-IP across cell types plus purified-protein direct binding\",\n      \"pmids\": [\"37761933\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of TFIIIC interaction untested\", \"Whether interactions are simultaneous or distinct complexes unknown\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Showed phosphorylation tunes SMARCAD1 activity by weakening nucleosome/DNA/H2A-H2B binding and ATP hydrolysis, and identified the N-terminus as critical for assembly/exchange.\",\n      \"evidence\": \"In vitro ATPase/exchange/assembly assays with phospho-site mutants and mass spectrometry\",\n      \"pmids\": [\"39424143\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Responsible kinase(s) in this context not defined\", \"In vivo relevance of these phospho-sites untested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Implicated SMARCAD1 in proviral silencing, showing it stabilizes Trim28 binding and H3.3 deposition to repress MLV in ESCs.\",\n      \"evidence\": \"MLV-GFP reporter, ChIP for Trim28/H3.3, single and double knockdown\",\n      \"pmids\": [\"38468276\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of H3.3 deposition support unclear\", \"Trim28-independent component undefined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Proposed SMARCAD1 as an R-loop-resolving factor at replication forks, binding R-loops via its ATPase domain and the replisome via its N-terminus (preprint).\",\n      \"evidence\": \"In vitro R-loop binding, replisome Co-IP, domain mutants, DRIP-seq (preprint)\",\n      \"pmids\": [\"bio_10.1101_2024.09.13.612941\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not peer-reviewed\", \"Direct enzymatic R-loop resolution vs displacement not distinguished\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Resolved the structural basis of substrate selectivity, showing SMARCAD1 prefers hexasomes over canonical nucleosomes and is co-activated by FACT plus H2A-H2B.\",\n      \"evidence\": \"Cryo-EM of SMARCAD1-hexasome and -nucleosome complexes, remodeling assays, mutagenesis of family-specific elements, FACT co-activity\",\n      \"pmids\": [\"40468067\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"When hexasome substrates arise in vivo not defined\", \"Link between hexasome preference and specific repair pathways unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Tied SMARCAD1 to embryonic heterochromatin via TOPBP1 partnership, with depletion causing H3K9me3 loss and developmental arrest.\",\n      \"evidence\": \"Chromatome profiling, live-cell imaging in ESC vs 2C-like cells, embryo depletion, H3K9me3 ChIP/immunostaining\",\n      \"pmids\": [\"39969508\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct vs indirect TOPBP1 contact not mapped\", \"Mechanism of nuclear export in 2C-like state unknown\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Reconstituted SMARCAD1's role in chromatin-context MMR across O6-methylguanine lesions, showing it sustains single-strand break retention during futile MMR cycling.\",\n      \"evidence\": \"Xenopus egg extract MMR reconstitution with Smarcad1 immunodepletion\",\n      \"pmids\": [\"39882945\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular step of SSB retention unclear\", \"Mammalian cell confirmation lacking\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Showed the yeast ortholog Fun30 dampens checkpoint signaling by displacing Rad9 with Slx4, enabling Exo1 resection and fork stabilization.\",\n      \"evidence\": \"Locus-specific ChIP at CPT-stalled forks, Fun30/Slx4/Exo1 epistasis, checkpoint and fiber assays\",\n      \"pmids\": [\"41978269\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conservation of Rad9/53BP1 displacement mechanism to human SMARCAD1 untested at this locus\", \"Yeast ortholog data\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How SMARCAD1's distinct activities (resection, fork protection, MMR, heterochromatin assembly, transcriptional activation) are selectively deployed at the right substrate and locus remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking hexasome preference and phospho-regulation to pathway choice\", \"In vivo upstream signals that partition functions undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [0, 1, 8, 15]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [8, 9, 15]},\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [3, 8]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [19]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [8, 13]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [4, 16]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [0, 7]},\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [1, 5, 6]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [0, 2, 12]},\n      {\"term_id\": \"R-HSA-69306\", \"supporting_discovery_ids\": [1, 7]},\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [1, 4, 16]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TRIM28\", \"PCNA\", \"HDAC1\", \"MSH2\", \"MSH6\", \"MLH1\", \"TFIIIC\", \"TOPBP1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}