{"gene":"ANP32E","run_date":"2026-06-09T22:02:43","timeline":{"discoveries":[{"year":2014,"finding":"ANP32E is a histone chaperone that specifically removes H2A.Z from chromatin. It is a member of the p400/TIP60 H2A.Z histone-exchange complex and interacts with a short region of the docking domain of H2A.Z through a novel motif called the H2A.Z interacting domain (ZID). Crystal structure at 1.48 Å of the ANP32E-ZID/H2A.Z/H2B complex reveals that ANP32E stabilizes the H2A.Z/H2B dimer through a specific extension of the H2A.Z C-terminal α-helix. In ANP32E-knockout cells, H2A.Z shows genome-wide enrichment and accumulation at enhancers and insulators.","method":"Crystal structure (1.48 Å), Co-IP, co-fractionation, biochemical pulldown, chromatin immunoprecipitation followed by sequencing (ChIP-seq) in ANP32E-/- cells","journal":"Nature","confidence":"High","confidence_rationale":"Tier 1 / Strong — high-resolution crystal structure plus mutagenesis, biochemical reconstitution, and genome-wide functional validation; independently corroborated by other labs","pmids":["24463511"],"is_preprint":false},{"year":2014,"finding":"Anp32e preferentially associates with H2A.Z-H2B dimers over canonical H2A-H2B dimers both in vitro and in vivo. Crystal structure of the Anp32e chaperone domain (residues 186–232) bound to H2A.Z-H2B shows that residues 214–224 (absent in other Anp32 family members) specifically contact the extended H2A.Z αC helix. Overexpression of Anp32e causes global H2A.Z loss at +1 nucleosomes; depletion causes moderate global H2A.Z increase at +1 nucleosomes.","method":"Crystal structure, in vitro binding assays, genome-wide ChIP-seq, gain- and loss-of-function experiments","journal":"Cell Research","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with functional validation across multiple orthogonal methods; independently replicates and extends PMID:24463511","pmids":["24613878"],"is_preprint":false},{"year":2015,"finding":"Anp32e is rapidly recruited to DNA double-strand breaks (DSBs) and removes H2A.Z from nucleosomes, returning H2A.Z levels to basal within 10 min of DNA damage. H2A.Z removal by Anp32e disrupts inhibitory interactions between the histone H4 tail and the nucleosome surface, facilitating H4 acetylation. Loss of Anp32e leads to elevated nucleosomal H2A.Z, hypoacetylated chromatin at DSBs, increased CtIP-dependent end resection, ssDNA accumulation, and increased alternative non-homologous end joining repair.","method":"Live-cell imaging of DSB-recruited Anp32e, ChIP at DSBs, knockdown/knockout with specific repair pathway readouts, H4 acetylation assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (ChIP, live imaging, repair pathway assays) in a single study, with specific functional readouts","pmids":["26034280"],"is_preprint":false},{"year":2006,"finding":"Anp32e/Cpd1 co-localizes with protein phosphatase 2A (PP2A) at synapses during cerebellar synaptogenesis. Synaptic Anp32e interacts with and inhibits PP2A activity. Phosphorylation of Anp32e is required for the Anp32e–PP2A interaction. A high-molecular-weight (74/76 kDa) membrane-bound form of Anp32e is expressed in a spatiotemporal pattern correlated with the cerebellar synaptogenesis period.","method":"Co-immunoprecipitation, PP2A activity assays, subcellular fractionation, electron microscopy, phosphorylation assays, ataxic mutant mouse models","journal":"The European Journal of Neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP with PP2A activity assay and phosphorylation requirement shown in a single lab with multiple methods","pmids":["16420440"],"is_preprint":false},{"year":2018,"finding":"ANP32E interacts with H2A.Z (C-terminus of ANP32E with N-terminus of H2A.Z, identified by yeast two-hybrid). ANP32E knockdown leads to proteasomal degradation and nuclear depletion of H2A.Z; this is reversed by PP2A inhibition and reproduced by PP2A catalytic subunit overexpression. ANP32E knockdown reduces H2A.Z phosphorylation; mutation of H2A.Z serine-9 abrogates its protein stability and nuclear localization. Nuclear mitogen and stress-induced kinase 1 (MSK1) knockdown phenocopies this effect.","method":"Yeast two-hybrid, knockdown, GFP-H2A.Z chimera, PP2A inhibitor treatment, site-directed mutagenesis (S9A), genome-wide ChIP-seq","journal":"Biochimica et Biophysica Acta: Gene Regulatory Mechanisms","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple methods (Y2H, mutagenesis, ChIP-seq, pharmacological rescue) in a single lab","pmids":["29524612"],"is_preprint":false},{"year":2020,"finding":"ANP32E antagonizes H2A.Z accumulation genome-wide to restrict chromatin accessibility in mouse fibroblasts. In the absence of ANP32E, H2A.Z accumulates at promoters in a hierarchical manner (first downstream, then upstream of the TSS), coinciding with improved nucleosome positioning, increased transcription factor binding, and elevated neighboring gene expression.","method":"ATAC-seq, ChIP-seq, ANP32E knockout mouse fibroblasts, MNase-seq, RNA-seq","journal":"Nature Communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — genome-wide functional genomics with multiple orthogonal assays in knockout cells, demonstrating mechanistic hierarchical H2A.Z accumulation","pmids":["33033242"],"is_preprint":false},{"year":2021,"finding":"In post-mitotic neurons, Anp32e regulates H2A.Z binding under steady-state conditions. Anp32e depletion causes H2A.Z-dependent impairment in transcription and dendritic arborization in cultured hippocampal neurons. In vivo, Anp32e depletion impairs recall of contextual fear memory and transcriptional regulation. Anp32e has lesser impact on stimulus-induced (activity-dependent) H2A.Z removal compared to steady-state regulation.","method":"Conditional knockdown in hippocampal neurons, ChIP-seq, RNA-seq, fear-conditioning behavioral assay, dendritic morphology analysis","journal":"Cell Reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (ChIP-seq, RNA-seq, behavioral assay, morphology) in a single study with clean loss-of-function","pmids":["34407406"],"is_preprint":false},{"year":2022,"finding":"In zebrafish, Anp32e restricts H2A.Z accumulation specifically at Sox motif-containing promoters. Genetic removal of Anp32e leads to precocious H2A.Z accumulation and premature transcriptional activation of Sox motif-associated developmental genes before gastrulation.","method":"Genetic knockout of anp32e in zebrafish, ChIP-seq, RNA-seq","journal":"Developmental Biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic loss-of-function in zebrafish with genome-wide ChIP-seq and RNA-seq, replicated in preprint (PMID:38187710)","pmids":["38159623","38187710"],"is_preprint":false},{"year":2022,"finding":"Anp32e promotes renal interstitial fibrosis by upregulating TGF-β1 and p-Smad3, leading to deposition of fibronectin and collagen type I. Overexpression of Anp32e alone (without TGF-β1 stimulation) induces fibrosis-related protein deposition; this is reversed by the TGF-β1 inhibitor SB431542, placing Anp32e upstream of the TGF-β1/Smad3 pathway.","method":"Gain- and loss-of-function in BUMPT cells and UUO mouse model, western blot, TGF-β1 inhibitor rescue assay","journal":"International Journal of Biological Sciences","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — genetic gain/loss-of-function with pharmacological rescue, single lab, no direct biochemical mechanism shown","pmids":["36263179"],"is_preprint":false},{"year":2024,"finding":"ANP32E preferentially interacts with H2A.Z during the G1 phase of the cell cycle in both cytoplasm and nucleoplasm of human U2OS cells. Most ANP32E is cytoplasmic, not chromatin-associated, and is not a stable component of the p400 remodeling complex. In the cytoplasm, ANP32E interacts with H2A.Z in G1 in response to increased H2A.Z protein abundance and regulates H2A.Z protein stability. This challenges the model that ANP32E removes H2A.Z from chromatin as part of a remodeling complex.","method":"Cell cycle synchronization, Co-IP, subcellular fractionation, mass spectrometry, U2OS cell knockdown with growth assays","journal":"Molecular and Cellular Biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple biochemical methods (Co-IP, fractionation, MS) in a single lab, but contradicts prior models; lower confidence due to conflict with established findings","pmids":["38482865"],"is_preprint":false},{"year":2025,"finding":"ANP32E-driven H2A.Z turnover alters RNA polymerase II processivity, leading to accumulation of long R-loops at transcription-replication conflict (TRC) sites. ANP32E overexpression enhances TRC formation and activates ATR-dependent DNA damage response, predisposing cancer cells to R-loop-mediated genomic fragility. Tumors with co-upregulation of MYC and ANP32E show increased genomic instability.","method":"Genome-wide R-loop mapping (DRIP-seq), RNA Pol II ChIP-seq, ATR inhibitor sensitivity assays, ANP32E overexpression in breast cancer cells, patient genomic data analysis","journal":"Nature Communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple genome-wide assays plus functional drug sensitivity data in a single study, but mechanistic link between ANP32E and R-loop induction is indirect","pmids":["40382323"],"is_preprint":false},{"year":2026,"finding":"ANP32E and the SRCAP subunit VPS72 co-occupy active gene promoters and function antagonistically on H2A.Z. VPS72 promotes H2A.Z incorporation, acetylation, BRG1 recruitment, and transcription; ANP32E constrains these features by stabilizing nucleosomes. Loss of ANP32E increases VPS72 binding, chromatin accessibility, and transcription; co-depletion of VPS72 reverses these effects. In vitro reconstitution assays demonstrate that ANP32E promotes nucleosome assembly and prevents DNA unwrapping.","method":"ChIP-seq, ATAC-seq, RNA-seq, genetic co-depletion epistasis, in vitro nucleosome reconstitution assays","journal":"Research Square (preprint)","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — reconstitution assay plus functional genomics, but preprint, single lab, not yet peer-reviewed","pmids":["41646306"],"is_preprint":true},{"year":2018,"finding":"ANP32E promotes G1/S cell cycle transition in triple-negative breast cancer cells by transcriptionally inducing E2F1. ANP32E inhibition suppresses tumor formation in vivo.","method":"siRNA knockdown, overexpression, cell cycle analysis, E2F1/cyclin E expression analysis, xenograft mouse model","journal":"Molecular Oncology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, transcriptional induction inferred from expression changes without direct mechanistic assay (e.g., ChIP at E2F1 promoter not shown in abstract)","pmids":["29633513"],"is_preprint":false},{"year":2024,"finding":"ANP32E regulates esophageal cancer progression and ferroptosis via the p53/SLC7A11 axis. ANP32E depletion increases p53 expression; p53 inhibition partially reverses the suppressed proliferation and enhanced ferroptosis in ANP32E-depleted cells.","method":"ANP32E knockout cell models, xenograft, RNA-seq, ferroptosis inhibitor rescue (ferrostatin-1), p53 inhibitor rescue, western blot","journal":"International Immunopharmacology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — functional rescue experiments place ANP32E upstream of p53/SLC7A11, but molecular mechanism linking H2A.Z chaperone activity to p53 regulation is not established in the abstract","pmids":["39566382"],"is_preprint":false}],"current_model":"ANP32E is a histone H2A.Z-specific chaperone that preferentially binds H2A.Z/H2B dimers through a unique ZID motif contacting the extended H2A.Z αC-helix (established by crystal structure); it removes H2A.Z from nucleosomes at active gene promoters, enhancers, insulators, and DNA double-strand break sites, antagonizing H2A.Z deposition factors (e.g., SRCAP subunit VPS72) to restrict chromatin accessibility and nucleosome dynamics genome-wide, with roles in DSB repair pathway choice (via CtIP-dependent end resection), neuronal transcription and memory, developmental gene regulation, and cell cycle-dependent regulation of the soluble H2A.Z pool, while also inhibiting PP2A activity at synapses during synaptogenesis."},"narrative":{"mechanistic_narrative":"ANP32E is a histone chaperone that specifically removes the histone variant H2A.Z from chromatin to restrict nucleosome dynamics and chromatin accessibility genome-wide [PMID:24463511, PMID:33033242]. It recognizes H2A.Z/H2B dimers through a dedicated H2A.Z-interacting domain (ZID) whose residues contact the extended H2A.Z C-terminal αC-helix, a contact resolved at high resolution by crystallography and conferring preference for H2A.Z over canonical H2A [PMID:24463511, PMID:24613878]. At active promoters, enhancers, and insulators, ANP32E counteracts H2A.Z deposition—directly antagonizing the SRCAP subunit VPS72 by stabilizing nucleosomes and preventing DNA unwrapping—so that its loss elevates H2A.Z, improves nucleosome positioning, increases transcription factor binding, and raises neighboring gene expression [PMID:33033242, PMID:41646306]. The same activity operates in defined biological contexts: ANP32E is rapidly recruited to DNA double-strand breaks where H2A.Z removal permits H4 acetylation and limits CtIP-dependent end resection and alternative non-homologous end joining [PMID:26034280]; in post-mitotic neurons it maintains steady-state H2A.Z occupancy to support transcription, dendritic arborization, and contextual fear memory [PMID:34407406]; and in zebrafish it restricts precocious H2A.Z accumulation and premature activation of Sox-motif developmental genes before gastrulation [PMID:38159623, PMID:38187710]. Beyond its chromatin role, a largely cytoplasmic ANP32E pool interacts with H2A.Z during G1 to govern H2A.Z protein stability, with H2A.Z stabilization dependent on phosphorylation and antagonized by PP2A [PMID:38482865, PMID:29524612]. ANP32E also inhibits PP2A activity at cerebellar synapses during synaptogenesis in a phosphorylation-dependent manner [PMID:16420440]. Excess ANP32E-driven H2A.Z turnover alters RNA polymerase II processivity and promotes R-loop accumulation and genomic instability at transcription-replication conflict sites [PMID:40382323].","teleology":[{"year":2014,"claim":"Established that ANP32E is a dedicated H2A.Z-removing chaperone and defined the structural basis for its variant specificity, answering how a single factor discriminates H2A.Z from canonical H2A.","evidence":"Crystal structure of the ANP32E-ZID/H2A.Z/H2B complex with biochemical pulldowns and ChIP-seq in knockout cells; independently corroborated by in vitro binding and gain/loss-of-function ChIP-seq","pmids":["24463511","24613878"],"confidence":"High","gaps":["Whether ANP32E acts catalytically or stoichiometrically in vivo not resolved","Recruitment determinants to specific genomic sites not defined"]},{"year":2015,"claim":"Showed ANP32E-mediated H2A.Z removal is functionally coupled to DNA damage response, defining a role in repair pathway choice.","evidence":"Live-cell imaging of DSB recruitment, ChIP at breaks, H4 acetylation assays, and repair pathway readouts in depleted cells","pmids":["26034280"],"confidence":"High","gaps":["Signal recruiting ANP32E to breaks not identified","Direct link between H2A.Z removal and end-resection machinery not biochemically reconstituted"]},{"year":2020,"claim":"Demonstrated genome-wide that ANP32E restricts chromatin accessibility, establishing a hierarchical mechanism of H2A.Z accumulation around the TSS upon its loss.","evidence":"ATAC-seq, ChIP-seq, MNase-seq, and RNA-seq in knockout mouse fibroblasts","pmids":["33033242"],"confidence":"High","gaps":["Causal order linking accessibility, TF binding, and transcription not fully dissected","Tissue-specificity of the effect not addressed"]},{"year":2021,"claim":"Distinguished steady-state from activity-dependent H2A.Z regulation in neurons and tied ANP32E to transcription, morphology, and memory.","evidence":"Conditional knockdown in hippocampal neurons with ChIP-seq, RNA-seq, dendritic morphology, and fear-conditioning behavior","pmids":["34407406"],"confidence":"High","gaps":["Molecular basis for preference of steady-state over stimulus-induced removal unknown","Specific neuronal gene targets driving behavior not pinpointed"]},{"year":2022,"claim":"Showed ANP32E restrains developmental gene activation by limiting H2A.Z at Sox-motif promoters, extending its role to embryonic timing.","evidence":"Genetic knockout in zebrafish with ChIP-seq and RNA-seq","pmids":["38159623","38187710"],"confidence":"High","gaps":["Why Sox-motif promoters are preferentially affected not explained","Connection to maternal-to-zygotic transition regulators not established"]},{"year":2018,"claim":"Linked ANP32E to PP2A-dependent regulation of H2A.Z protein stability and nuclear localization through phosphorylation.","evidence":"Yeast two-hybrid, H2A.Z S9A mutagenesis, PP2A inhibitor/overexpression rescue, MSK1 knockdown, and ChIP-seq","pmids":["29524612"],"confidence":"Medium","gaps":["Direct kinase acting on H2A.Z S9 in this pathway not definitively established","Relationship between stability control and chromatin removal activity unclear"]},{"year":2006,"claim":"Identified an early, non-chromatin role for ANP32E (Cpd1) as a phosphorylation-dependent inhibitor of PP2A at synapses during synaptogenesis.","evidence":"Co-IP, PP2A activity assays, subcellular fractionation, electron microscopy, and ataxic mutant mouse models","pmids":["16420440"],"confidence":"Medium","gaps":["Relationship between the membrane-bound 74/76 kDa form and the chromatin chaperone not reconciled","Direct synaptic substrates of inhibited PP2A not defined"]},{"year":2024,"claim":"Challenged the chromatin-remodeling-complex model by showing most ANP32E is cytoplasmic and engages H2A.Z in a G1-restricted, abundance-driven manner to control protein stability.","evidence":"Cell cycle synchronization, Co-IP, fractionation, mass spectrometry, and growth assays in U2OS cells","pmids":["38482865"],"confidence":"Medium","gaps":["Conflicts with the stable p400-complex model and not yet reconciled","Mechanism coupling cytoplasmic stability control to nuclear H2A.Z eviction unknown"]},{"year":2025,"claim":"Connected ANP32E-driven H2A.Z turnover to RNA Pol II processivity, R-loop accumulation, and genomic instability in cancer.","evidence":"DRIP-seq, RNA Pol II ChIP-seq, ATR-inhibitor sensitivity, overexpression in breast cancer cells, and patient genomic analysis","pmids":["40382323"],"confidence":"Medium","gaps":["Mechanistic link between H2A.Z turnover and R-loop induction is indirect","Whether MYC-ANP32E co-upregulation is causal or correlative not established"]},{"year":2026,"claim":"Defined a direct antagonism between ANP32E and the SRCAP subunit VPS72 at active promoters and reconstituted ANP32E's nucleosome-stabilizing activity.","evidence":"ChIP-seq, ATAC-seq, RNA-seq, genetic co-depletion epistasis, and in vitro nucleosome reconstitution (preprint)","pmids":["41646306"],"confidence":"Medium","gaps":["Preprint, single lab, not yet peer-reviewed","Whether antagonism is direct competition for H2A.Z or independent opposing activities not fully resolved"]},{"year":null,"claim":"How ANP32E's cytoplasmic H2A.Z-stability function and its chromatin-eviction activity are mechanistically integrated, and how it is targeted to specific genomic loci, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model reconciling cytoplasmic vs chromatin roles","Locus-targeting determinants undefined","Stoichiometry/dynamics of removal vs deposition antagonism not quantified"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[0,1,5]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[3,4]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,5]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[9]},{"term_id":"GO:0005654","term_label":"nucleoplasm","supporting_discovery_ids":[9]}],"pathway":[{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[0,5,11]},{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[2]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[5,6,7]}],"complexes":["p400/TIP60 H2A.Z histone-exchange complex"],"partners":["H2AFZ","H2BC","VPS72","PPP2CA"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9BTT0","full_name":"Acidic leucine-rich nuclear phosphoprotein 32 family member E","aliases":["LANP-like protein","LANP-L"],"length_aa":268,"mass_kda":30.7,"function":"Histone chaperone that specifically mediates the genome-wide removal of histone H2A.Z/H2AZ1 from the nucleosome: removes H2A.Z/H2AZ1 from its normal sites of deposition, especially from enhancer and insulator regions. Not involved in deposition of H2A.Z/H2AZ1 in the nucleosome. May stabilize the evicted H2A.Z/H2AZ1-H2B dimer, thus shifting the equilibrium towards dissociation and the off-chromatin state (PubMed:24463511). Inhibits activity of protein phosphatase 2A (PP2A). Does not inhibit protein phosphatase 1. May play a role in cerebellar development and synaptogenesis","subcellular_location":"Cytoplasm; Nucleus","url":"https://www.uniprot.org/uniprotkb/Q9BTT0/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ANP32E","classification":"Not Classified","n_dependent_lines":138,"n_total_lines":1208,"dependency_fraction":0.11423841059602649},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"H2AFZ","stoichiometry":0.2},{"gene":"HIST2H2BE","stoichiometry":0.2},{"gene":"KPNA1","stoichiometry":0.2},{"gene":"KPNA6","stoichiometry":0.2},{"gene":"SRP9","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/ANP32E","total_profiled":1310},"omim":[{"mim_id":"609611","title":"ACIDIC LEUCINE-RICH NUCLEAR PHOSPHOPROTEIN 32 FAMILY, MEMBER E; ANP32E","url":"https://www.omim.org/entry/609611"},{"mim_id":"606265","title":"E1A-BINDING PROTEIN, 400-KD; EP400","url":"https://www.omim.org/entry/606265"},{"mim_id":"601409","title":"LYSINE ACETYLTRANSFERASE 5; KAT5","url":"https://www.omim.org/entry/601409"},{"mim_id":"142763","title":"H2A.Z VARIANT HISTONE 1; H2AZ1","url":"https://www.omim.org/entry/142763"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"},{"location":"Centrosome","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ANP32E"},"hgnc":{"alias_symbol":["LANPL","MGC5350","LANP-L"],"prev_symbol":[]},"alphafold":{"accession":"Q9BTT0","domains":[{"cath_id":"3.80.10.10","chopping":"2-144","consensus_level":"high","plddt":93.9061,"start":2,"end":144}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BTT0","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BTT0-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BTT0-F1-predicted_aligned_error_v6.png","plddt_mean":76.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ANP32E","jax_strain_url":"https://www.jax.org/strain/search?query=ANP32E"},"sequence":{"accession":"Q9BTT0","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9BTT0.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9BTT0/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BTT0"}},"corpus_meta":[{"pmid":"24463511","id":"PMC_24463511","title":"ANP32E is a histone chaperone that removes H2A.Z from chromatin.","date":"2014","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/24463511","citation_count":221,"is_preprint":false},{"pmid":"26034280","id":"PMC_26034280","title":"Histone chaperone Anp32e removes H2A.Z from DNA double-strand breaks and promotes nucleosome reorganization and DNA repair.","date":"2015","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/26034280","citation_count":119,"is_preprint":false},{"pmid":"24613878","id":"PMC_24613878","title":"Anp32e, a higher eukaryotic histone chaperone directs preferential recognition for H2A.Z.","date":"2014","source":"Cell research","url":"https://pubmed.ncbi.nlm.nih.gov/24613878","citation_count":112,"is_preprint":false},{"pmid":"28220627","id":"PMC_28220627","title":"Downregulation of miRNA-141 in breast cancer cells is associated with cell migration and invasion: involvement of ANP32E targeting.","date":"2017","source":"Cancer medicine","url":"https://pubmed.ncbi.nlm.nih.gov/28220627","citation_count":79,"is_preprint":false},{"pmid":"29633513","id":"PMC_29633513","title":"ANP32E induces tumorigenesis of triple-negative breast cancer cells by upregulating E2F1.","date":"2018","source":"Molecular oncology","url":"https://pubmed.ncbi.nlm.nih.gov/29633513","citation_count":51,"is_preprint":false},{"pmid":"33033242","id":"PMC_33033242","title":"Genome-wide chromatin accessibility is restricted by ANP32E.","date":"2020","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/33033242","citation_count":43,"is_preprint":false},{"pmid":"14964690","id":"PMC_14964690","title":"Anp32e (Cpd1) and related protein phosphatase 2 inhibitors.","date":"2003","source":"Cerebellum (London, England)","url":"https://pubmed.ncbi.nlm.nih.gov/14964690","citation_count":37,"is_preprint":false},{"pmid":"30329026","id":"PMC_30329026","title":"ANP32E, a Protein Involved in Steroid-Refractoriness in Ulcerative Colitis, Identified by a Systems Biology Approach.","date":"2019","source":"Journal of Crohn's & colitis","url":"https://pubmed.ncbi.nlm.nih.gov/30329026","citation_count":36,"is_preprint":false},{"pmid":"16420440","id":"PMC_16420440","title":"Anp32e/Cpd1 regulates protein phosphatase 2A activity at synapses during synaptogenesis.","date":"2006","source":"The European journal of neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/16420440","citation_count":27,"is_preprint":false},{"pmid":"32304784","id":"PMC_32304784","title":"Up-regulated ANP32E promotes the thyroid carcinoma cell proliferation and migration via activating AKT/mTOR/HK2-mediated glycolysis.","date":"2020","source":"Gene","url":"https://pubmed.ncbi.nlm.nih.gov/32304784","citation_count":25,"is_preprint":false},{"pmid":"21049064","id":"PMC_21049064","title":"Generation and characterization of the Anp32e-deficient mouse.","date":"2010","source":"PloS 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Gene regulatory mechanisms","url":"https://pubmed.ncbi.nlm.nih.gov/29524612","citation_count":12,"is_preprint":false},{"pmid":"12438741","id":"PMC_12438741","title":"Molecular cloning and characterization of a novel human gene (ANP32E alias LANPL) from human fetal brain.","date":"2002","source":"Cytogenetic and genome research","url":"https://pubmed.ncbi.nlm.nih.gov/12438741","citation_count":8,"is_preprint":false},{"pmid":"34922480","id":"PMC_34922480","title":"Subtype-Independent ANP32E Reduction During Breast Cancer Progression in Accordance with Chromatin Relaxation.","date":"2021","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/34922480","citation_count":8,"is_preprint":false},{"pmid":"38159623","id":"PMC_38159623","title":"Anp32e protects against accumulation of H2A.Z at Sox motif containing promoters during zebrafish gastrulation.","date":"2023","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/38159623","citation_count":6,"is_preprint":false},{"pmid":"38482865","id":"PMC_38482865","title":"ANP32e Binds Histone H2A.Z in a Cell Cycle-Dependent Manner and Regulates Its Protein Stability in the Cytoplasm.","date":"2024","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/38482865","citation_count":5,"is_preprint":false},{"pmid":"40382323","id":"PMC_40382323","title":"ANP32E drives vulnerability to ATR inhibitors by inducing R-loops-dependent transcription replication conflicts in triple negative breast cancer.","date":"2025","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/40382323","citation_count":4,"is_preprint":false},{"pmid":"23675506","id":"PMC_23675506","title":"Targeted ANP32E mutant mice do not demonstrate obvious movement defects.","date":"2013","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/23675506","citation_count":4,"is_preprint":false},{"pmid":"38944356","id":"PMC_38944356","title":"FOXCUT regulates the malignant phenotype of triple-negative breast Cancer via the miR-337-3p/ANP32E Axis.","date":"2024","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/38944356","citation_count":3,"is_preprint":false},{"pmid":"38585643","id":"PMC_38585643","title":"Knockdown of ANP32E inhibits colorectal cancer cell growth and glycolysis by regulating the AKT/mTOR pathway.","date":"2024","source":"Open life sciences","url":"https://pubmed.ncbi.nlm.nih.gov/38585643","citation_count":2,"is_preprint":false},{"pmid":"40686617","id":"PMC_40686617","title":"Inhibiting ANP32E protects against acute kidney injury by regulating autophagy via the AMPK pathway.","date":"2025","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/40686617","citation_count":1,"is_preprint":false},{"pmid":"38187710","id":"PMC_38187710","title":"Anp32e protects against accumulation of H2A.Z at Sox motif containing promoters during zebrafish gastrulation.","date":"2023","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38187710","citation_count":0,"is_preprint":false},{"pmid":"41646306","id":"PMC_41646306","title":"Cooperative and Opposing Functions of ANP32E and VPS72 Govern Gene Promoter Chromatin Status.","date":"2026","source":"Research square","url":"https://pubmed.ncbi.nlm.nih.gov/41646306","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":15267,"output_tokens":4069,"usd":0.053418,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11978,"output_tokens":3724,"usd":0.076495,"stage2_stop_reason":"end_turn"},"total_usd":0.129913,"stage1_batch_id":"msgbatch_0179Z2pxRYBsXi2xADneafRw","stage2_batch_id":"msgbatch_01LaY9ZaVdgjWArcZo9eqQE5","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2014,\n      \"finding\": \"ANP32E is a histone chaperone that specifically removes H2A.Z from chromatin. It is a member of the p400/TIP60 H2A.Z histone-exchange complex and interacts with a short region of the docking domain of H2A.Z through a novel motif called the H2A.Z interacting domain (ZID). Crystal structure at 1.48 Å of the ANP32E-ZID/H2A.Z/H2B complex reveals that ANP32E stabilizes the H2A.Z/H2B dimer through a specific extension of the H2A.Z C-terminal α-helix. In ANP32E-knockout cells, H2A.Z shows genome-wide enrichment and accumulation at enhancers and insulators.\",\n      \"method\": \"Crystal structure (1.48 Å), Co-IP, co-fractionation, biochemical pulldown, chromatin immunoprecipitation followed by sequencing (ChIP-seq) in ANP32E-/- cells\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — high-resolution crystal structure plus mutagenesis, biochemical reconstitution, and genome-wide functional validation; independently corroborated by other labs\",\n      \"pmids\": [\"24463511\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Anp32e preferentially associates with H2A.Z-H2B dimers over canonical H2A-H2B dimers both in vitro and in vivo. Crystal structure of the Anp32e chaperone domain (residues 186–232) bound to H2A.Z-H2B shows that residues 214–224 (absent in other Anp32 family members) specifically contact the extended H2A.Z αC helix. Overexpression of Anp32e causes global H2A.Z loss at +1 nucleosomes; depletion causes moderate global H2A.Z increase at +1 nucleosomes.\",\n      \"method\": \"Crystal structure, in vitro binding assays, genome-wide ChIP-seq, gain- and loss-of-function experiments\",\n      \"journal\": \"Cell Research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with functional validation across multiple orthogonal methods; independently replicates and extends PMID:24463511\",\n      \"pmids\": [\"24613878\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Anp32e is rapidly recruited to DNA double-strand breaks (DSBs) and removes H2A.Z from nucleosomes, returning H2A.Z levels to basal within 10 min of DNA damage. H2A.Z removal by Anp32e disrupts inhibitory interactions between the histone H4 tail and the nucleosome surface, facilitating H4 acetylation. Loss of Anp32e leads to elevated nucleosomal H2A.Z, hypoacetylated chromatin at DSBs, increased CtIP-dependent end resection, ssDNA accumulation, and increased alternative non-homologous end joining repair.\",\n      \"method\": \"Live-cell imaging of DSB-recruited Anp32e, ChIP at DSBs, knockdown/knockout with specific repair pathway readouts, H4 acetylation assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (ChIP, live imaging, repair pathway assays) in a single study, with specific functional readouts\",\n      \"pmids\": [\"26034280\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Anp32e/Cpd1 co-localizes with protein phosphatase 2A (PP2A) at synapses during cerebellar synaptogenesis. Synaptic Anp32e interacts with and inhibits PP2A activity. Phosphorylation of Anp32e is required for the Anp32e–PP2A interaction. A high-molecular-weight (74/76 kDa) membrane-bound form of Anp32e is expressed in a spatiotemporal pattern correlated with the cerebellar synaptogenesis period.\",\n      \"method\": \"Co-immunoprecipitation, PP2A activity assays, subcellular fractionation, electron microscopy, phosphorylation assays, ataxic mutant mouse models\",\n      \"journal\": \"The European Journal of Neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP with PP2A activity assay and phosphorylation requirement shown in a single lab with multiple methods\",\n      \"pmids\": [\"16420440\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"ANP32E interacts with H2A.Z (C-terminus of ANP32E with N-terminus of H2A.Z, identified by yeast two-hybrid). ANP32E knockdown leads to proteasomal degradation and nuclear depletion of H2A.Z; this is reversed by PP2A inhibition and reproduced by PP2A catalytic subunit overexpression. ANP32E knockdown reduces H2A.Z phosphorylation; mutation of H2A.Z serine-9 abrogates its protein stability and nuclear localization. Nuclear mitogen and stress-induced kinase 1 (MSK1) knockdown phenocopies this effect.\",\n      \"method\": \"Yeast two-hybrid, knockdown, GFP-H2A.Z chimera, PP2A inhibitor treatment, site-directed mutagenesis (S9A), genome-wide ChIP-seq\",\n      \"journal\": \"Biochimica et Biophysica Acta: Gene Regulatory Mechanisms\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple methods (Y2H, mutagenesis, ChIP-seq, pharmacological rescue) in a single lab\",\n      \"pmids\": [\"29524612\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"ANP32E antagonizes H2A.Z accumulation genome-wide to restrict chromatin accessibility in mouse fibroblasts. In the absence of ANP32E, H2A.Z accumulates at promoters in a hierarchical manner (first downstream, then upstream of the TSS), coinciding with improved nucleosome positioning, increased transcription factor binding, and elevated neighboring gene expression.\",\n      \"method\": \"ATAC-seq, ChIP-seq, ANP32E knockout mouse fibroblasts, MNase-seq, RNA-seq\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genome-wide functional genomics with multiple orthogonal assays in knockout cells, demonstrating mechanistic hierarchical H2A.Z accumulation\",\n      \"pmids\": [\"33033242\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"In post-mitotic neurons, Anp32e regulates H2A.Z binding under steady-state conditions. Anp32e depletion causes H2A.Z-dependent impairment in transcription and dendritic arborization in cultured hippocampal neurons. In vivo, Anp32e depletion impairs recall of contextual fear memory and transcriptional regulation. Anp32e has lesser impact on stimulus-induced (activity-dependent) H2A.Z removal compared to steady-state regulation.\",\n      \"method\": \"Conditional knockdown in hippocampal neurons, ChIP-seq, RNA-seq, fear-conditioning behavioral assay, dendritic morphology analysis\",\n      \"journal\": \"Cell Reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (ChIP-seq, RNA-seq, behavioral assay, morphology) in a single study with clean loss-of-function\",\n      \"pmids\": [\"34407406\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"In zebrafish, Anp32e restricts H2A.Z accumulation specifically at Sox motif-containing promoters. Genetic removal of Anp32e leads to precocious H2A.Z accumulation and premature transcriptional activation of Sox motif-associated developmental genes before gastrulation.\",\n      \"method\": \"Genetic knockout of anp32e in zebrafish, ChIP-seq, RNA-seq\",\n      \"journal\": \"Developmental Biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic loss-of-function in zebrafish with genome-wide ChIP-seq and RNA-seq, replicated in preprint (PMID:38187710)\",\n      \"pmids\": [\"38159623\", \"38187710\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Anp32e promotes renal interstitial fibrosis by upregulating TGF-β1 and p-Smad3, leading to deposition of fibronectin and collagen type I. Overexpression of Anp32e alone (without TGF-β1 stimulation) induces fibrosis-related protein deposition; this is reversed by the TGF-β1 inhibitor SB431542, placing Anp32e upstream of the TGF-β1/Smad3 pathway.\",\n      \"method\": \"Gain- and loss-of-function in BUMPT cells and UUO mouse model, western blot, TGF-β1 inhibitor rescue assay\",\n      \"journal\": \"International Journal of Biological Sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — genetic gain/loss-of-function with pharmacological rescue, single lab, no direct biochemical mechanism shown\",\n      \"pmids\": [\"36263179\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ANP32E preferentially interacts with H2A.Z during the G1 phase of the cell cycle in both cytoplasm and nucleoplasm of human U2OS cells. Most ANP32E is cytoplasmic, not chromatin-associated, and is not a stable component of the p400 remodeling complex. In the cytoplasm, ANP32E interacts with H2A.Z in G1 in response to increased H2A.Z protein abundance and regulates H2A.Z protein stability. This challenges the model that ANP32E removes H2A.Z from chromatin as part of a remodeling complex.\",\n      \"method\": \"Cell cycle synchronization, Co-IP, subcellular fractionation, mass spectrometry, U2OS cell knockdown with growth assays\",\n      \"journal\": \"Molecular and Cellular Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple biochemical methods (Co-IP, fractionation, MS) in a single lab, but contradicts prior models; lower confidence due to conflict with established findings\",\n      \"pmids\": [\"38482865\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ANP32E-driven H2A.Z turnover alters RNA polymerase II processivity, leading to accumulation of long R-loops at transcription-replication conflict (TRC) sites. ANP32E overexpression enhances TRC formation and activates ATR-dependent DNA damage response, predisposing cancer cells to R-loop-mediated genomic fragility. Tumors with co-upregulation of MYC and ANP32E show increased genomic instability.\",\n      \"method\": \"Genome-wide R-loop mapping (DRIP-seq), RNA Pol II ChIP-seq, ATR inhibitor sensitivity assays, ANP32E overexpression in breast cancer cells, patient genomic data analysis\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple genome-wide assays plus functional drug sensitivity data in a single study, but mechanistic link between ANP32E and R-loop induction is indirect\",\n      \"pmids\": [\"40382323\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"ANP32E and the SRCAP subunit VPS72 co-occupy active gene promoters and function antagonistically on H2A.Z. VPS72 promotes H2A.Z incorporation, acetylation, BRG1 recruitment, and transcription; ANP32E constrains these features by stabilizing nucleosomes. Loss of ANP32E increases VPS72 binding, chromatin accessibility, and transcription; co-depletion of VPS72 reverses these effects. In vitro reconstitution assays demonstrate that ANP32E promotes nucleosome assembly and prevents DNA unwrapping.\",\n      \"method\": \"ChIP-seq, ATAC-seq, RNA-seq, genetic co-depletion epistasis, in vitro nucleosome reconstitution assays\",\n      \"journal\": \"Research Square (preprint)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — reconstitution assay plus functional genomics, but preprint, single lab, not yet peer-reviewed\",\n      \"pmids\": [\"41646306\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"ANP32E promotes G1/S cell cycle transition in triple-negative breast cancer cells by transcriptionally inducing E2F1. ANP32E inhibition suppresses tumor formation in vivo.\",\n      \"method\": \"siRNA knockdown, overexpression, cell cycle analysis, E2F1/cyclin E expression analysis, xenograft mouse model\",\n      \"journal\": \"Molecular Oncology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, transcriptional induction inferred from expression changes without direct mechanistic assay (e.g., ChIP at E2F1 promoter not shown in abstract)\",\n      \"pmids\": [\"29633513\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ANP32E regulates esophageal cancer progression and ferroptosis via the p53/SLC7A11 axis. ANP32E depletion increases p53 expression; p53 inhibition partially reverses the suppressed proliferation and enhanced ferroptosis in ANP32E-depleted cells.\",\n      \"method\": \"ANP32E knockout cell models, xenograft, RNA-seq, ferroptosis inhibitor rescue (ferrostatin-1), p53 inhibitor rescue, western blot\",\n      \"journal\": \"International Immunopharmacology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — functional rescue experiments place ANP32E upstream of p53/SLC7A11, but molecular mechanism linking H2A.Z chaperone activity to p53 regulation is not established in the abstract\",\n      \"pmids\": [\"39566382\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ANP32E is a histone H2A.Z-specific chaperone that preferentially binds H2A.Z/H2B dimers through a unique ZID motif contacting the extended H2A.Z αC-helix (established by crystal structure); it removes H2A.Z from nucleosomes at active gene promoters, enhancers, insulators, and DNA double-strand break sites, antagonizing H2A.Z deposition factors (e.g., SRCAP subunit VPS72) to restrict chromatin accessibility and nucleosome dynamics genome-wide, with roles in DSB repair pathway choice (via CtIP-dependent end resection), neuronal transcription and memory, developmental gene regulation, and cell cycle-dependent regulation of the soluble H2A.Z pool, while also inhibiting PP2A activity at synapses during synaptogenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ANP32E is a histone chaperone that specifically removes the histone variant H2A.Z from chromatin to restrict nucleosome dynamics and chromatin accessibility genome-wide [#0, #5]. It recognizes H2A.Z/H2B dimers through a dedicated H2A.Z-interacting domain (ZID) whose residues contact the extended H2A.Z C-terminal \\u03b1C-helix, a contact resolved at high resolution by crystallography and conferring preference for H2A.Z over canonical H2A [#0, #1]. At active promoters, enhancers, and insulators, ANP32E counteracts H2A.Z deposition\\u2014directly antagonizing the SRCAP subunit VPS72 by stabilizing nucleosomes and preventing DNA unwrapping\\u2014so that its loss elevates H2A.Z, improves nucleosome positioning, increases transcription factor binding, and raises neighboring gene expression [#5, #11]. The same activity operates in defined biological contexts: ANP32E is rapidly recruited to DNA double-strand breaks where H2A.Z removal permits H4 acetylation and limits CtIP-dependent end resection and alternative non-homologous end joining [#2]; in post-mitotic neurons it maintains steady-state H2A.Z occupancy to support transcription, dendritic arborization, and contextual fear memory [#6]; and in zebrafish it restricts precocious H2A.Z accumulation and premature activation of Sox-motif developmental genes before gastrulation [#7]. Beyond its chromatin role, a largely cytoplasmic ANP32E pool interacts with H2A.Z during G1 to govern H2A.Z protein stability, with H2A.Z stabilization dependent on phosphorylation and antagonized by PP2A [#9, #4]. ANP32E also inhibits PP2A activity at cerebellar synapses during synaptogenesis in a phosphorylation-dependent manner [#3]. Excess ANP32E-driven H2A.Z turnover alters RNA polymerase II processivity and promotes R-loop accumulation and genomic instability at transcription-replication conflict sites [#10].\",\n  \"teleology\": [\n    {\n      \"year\": 2014,\n      \"claim\": \"Established that ANP32E is a dedicated H2A.Z-removing chaperone and defined the structural basis for its variant specificity, answering how a single factor discriminates H2A.Z from canonical H2A.\",\n      \"evidence\": \"Crystal structure of the ANP32E-ZID/H2A.Z/H2B complex with biochemical pulldowns and ChIP-seq in knockout cells; independently corroborated by in vitro binding and gain/loss-of-function ChIP-seq\",\n      \"pmids\": [\"24463511\", \"24613878\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether ANP32E acts catalytically or stoichiometrically in vivo not resolved\", \"Recruitment determinants to specific genomic sites not defined\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Showed ANP32E-mediated H2A.Z removal is functionally coupled to DNA damage response, defining a role in repair pathway choice.\",\n      \"evidence\": \"Live-cell imaging of DSB recruitment, ChIP at breaks, H4 acetylation assays, and repair pathway readouts in depleted cells\",\n      \"pmids\": [\"26034280\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Signal recruiting ANP32E to breaks not identified\", \"Direct link between H2A.Z removal and end-resection machinery not biochemically reconstituted\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Demonstrated genome-wide that ANP32E restricts chromatin accessibility, establishing a hierarchical mechanism of H2A.Z accumulation around the TSS upon its loss.\",\n      \"evidence\": \"ATAC-seq, ChIP-seq, MNase-seq, and RNA-seq in knockout mouse fibroblasts\",\n      \"pmids\": [\"33033242\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Causal order linking accessibility, TF binding, and transcription not fully dissected\", \"Tissue-specificity of the effect not addressed\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Distinguished steady-state from activity-dependent H2A.Z regulation in neurons and tied ANP32E to transcription, morphology, and memory.\",\n      \"evidence\": \"Conditional knockdown in hippocampal neurons with ChIP-seq, RNA-seq, dendritic morphology, and fear-conditioning behavior\",\n      \"pmids\": [\"34407406\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis for preference of steady-state over stimulus-induced removal unknown\", \"Specific neuronal gene targets driving behavior not pinpointed\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Showed ANP32E restrains developmental gene activation by limiting H2A.Z at Sox-motif promoters, extending its role to embryonic timing.\",\n      \"evidence\": \"Genetic knockout in zebrafish with ChIP-seq and RNA-seq\",\n      \"pmids\": [\"38159623\", \"38187710\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Why Sox-motif promoters are preferentially affected not explained\", \"Connection to maternal-to-zygotic transition regulators not established\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Linked ANP32E to PP2A-dependent regulation of H2A.Z protein stability and nuclear localization through phosphorylation.\",\n      \"evidence\": \"Yeast two-hybrid, H2A.Z S9A mutagenesis, PP2A inhibitor/overexpression rescue, MSK1 knockdown, and ChIP-seq\",\n      \"pmids\": [\"29524612\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct kinase acting on H2A.Z S9 in this pathway not definitively established\", \"Relationship between stability control and chromatin removal activity unclear\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Identified an early, non-chromatin role for ANP32E (Cpd1) as a phosphorylation-dependent inhibitor of PP2A at synapses during synaptogenesis.\",\n      \"evidence\": \"Co-IP, PP2A activity assays, subcellular fractionation, electron microscopy, and ataxic mutant mouse models\",\n      \"pmids\": [\"16420440\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Relationship between the membrane-bound 74/76 kDa form and the chromatin chaperone not reconciled\", \"Direct synaptic substrates of inhibited PP2A not defined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Challenged the chromatin-remodeling-complex model by showing most ANP32E is cytoplasmic and engages H2A.Z in a G1-restricted, abundance-driven manner to control protein stability.\",\n      \"evidence\": \"Cell cycle synchronization, Co-IP, fractionation, mass spectrometry, and growth assays in U2OS cells\",\n      \"pmids\": [\"38482865\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conflicts with the stable p400-complex model and not yet reconciled\", \"Mechanism coupling cytoplasmic stability control to nuclear H2A.Z eviction unknown\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Connected ANP32E-driven H2A.Z turnover to RNA Pol II processivity, R-loop accumulation, and genomic instability in cancer.\",\n      \"evidence\": \"DRIP-seq, RNA Pol II ChIP-seq, ATR-inhibitor sensitivity, overexpression in breast cancer cells, and patient genomic analysis\",\n      \"pmids\": [\"40382323\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic link between H2A.Z turnover and R-loop induction is indirect\", \"Whether MYC-ANP32E co-upregulation is causal or correlative not established\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Defined a direct antagonism between ANP32E and the SRCAP subunit VPS72 at active promoters and reconstituted ANP32E's nucleosome-stabilizing activity.\",\n      \"evidence\": \"ChIP-seq, ATAC-seq, RNA-seq, genetic co-depletion epistasis, and in vitro nucleosome reconstitution (preprint)\",\n      \"pmids\": [\"41646306\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, single lab, not yet peer-reviewed\", \"Whether antagonism is direct competition for H2A.Z or independent opposing activities not fully resolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ANP32E's cytoplasmic H2A.Z-stability function and its chromatin-eviction activity are mechanistically integrated, and how it is targeted to specific genomic loci, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model reconciling cytoplasmic vs chromatin roles\", \"Locus-targeting determinants undefined\", \"Stoichiometry/dynamics of removal vs deposition antagonism not quantified\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [0, 1, 5]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [3, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 5]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [9]},\n      {\"term_id\": \"GO:0005654\", \"supporting_discovery_ids\": [9]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [0, 5, 11]},\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [5, 6, 7]}\n    ],\n    \"complexes\": [\"p400/TIP60 H2A.Z histone-exchange complex\"],\n    \"partners\": [\"H2AFZ\", \"H2BC\", \"VPS72\", \"PPP2CA\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}