{"gene":"ARFGAP2","run_date":"2026-06-09T22:02:44","timeline":{"discoveries":[{"year":2004,"finding":"The appendage domain of gamma-COP binds to ARFGAP2 (mammalian Glo3p orthologue) via a single protein-protein interaction site on its platform subdomain, analogous to the alpha-appendage of AP2.","method":"Crystal structure of gamma-COP appendage domain combined with protein-protein interaction binding assays","journal":"Traffic","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structure with functional validation of interaction site, single lab but orthogonal structural and binding methods","pmids":["14690497"],"is_preprint":false},{"year":2007,"finding":"ARFGAP2 and ARFGAP3 are human orthologues of yeast Glo3p; ARFGAP2 localizes to the Golgi complex and peripheral punctate structures colocalizing with coatomer subunits, is associated with COP-I-coated vesicles generated in vitro, and directly binds coatomer via a region outside its zinc finger domain. Expression of a truncated ARFGAP2 lacking its zinc finger domain (DeltaN-ARFGAP2) inhibits COP-I-dependent Golgi-to-ER transport of cholera toxin in vivo.","method":"Immunofluorescence colocalization, in vitro COP-I vesicle generation assay, pulldown binding assay with truncation mutant, dominant-negative inhibition of retrograde transport in vivo","journal":"Traffic","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (IF, in vitro vesicle assay, pulldown, in vivo transport assay) in single lab","pmids":["17760859"],"is_preprint":false},{"year":2008,"finding":"Unlike ArfGAP1, ARFGAP2 and ARFGAP3 do not bind directly to membranes but are recruited to the Golgi via interactions with coatomer. In the presence of coatomer, ARFGAP2 and ARFGAP3 GAP activities are comparable to or higher than ArfGAP1 activity, establishing that coatomer functions to stimulate ARFGAP2/3-catalyzed GTP hydrolysis on Arf1.","method":"In vitro GAP activity assays with recombinant proteins, membrane binding assays, coatomer-dependent recruitment assays","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution of GAP activity with recombinant proteins and defined conditions, single lab with multiple orthogonal assays","pmids":["19015319"],"is_preprint":false},{"year":2008,"finding":"The Golgi localization and catalytic activity of ARFGAP2/3 depends on coatomer interaction. A central basic stretch in ARFGAP3 interacts directly with coatomer and is essential for ArfGAP3 catalytic activity on Arf1-GTP, while a carboxy-amphipathic motif interacts directly with lipid membranes but plays only a minor role in regulating GAP activity.","method":"Reporter fusion Golgi localization assay, in vitro GAP activity assays, direct binding assays between isolated domains and coatomer or lipid membranes","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with domain mapping, multiple orthogonal methods, single lab","pmids":["19109418"],"is_preprint":false},{"year":2009,"finding":"The GAP domain together with the BoCCS (binding of coatomer, cargo, and SNAREs) region of yeast Glo3 (ArfGAP2/3 orthologue) is necessary and sufficient for all vital Glo3 functions. The BoCCS region interacts with coatomer, SNAREs, and cargo. A truncated Glo3 lacking the GAP domain acts as a dominant negative whose phenotype is alleviated by mutating the BoCCS region or the Glo3 regulatory motif (GRM), or by overexpression of ER-Golgi SNAREs.","method":"Yeast genetic epistasis, domain truncation/mutation analysis, dominant negative growth assay, genetic suppression","journal":"Traffic","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — yeast epistasis and genetic suppression with multiple domain mutants, single lab","pmids":["19602196"],"is_preprint":false},{"year":2009,"finding":"Simultaneous knockdown of ArfGAP1, ArfGAP2, and ArfGAP3 in mammalian cells increases GTP-bound ARF levels, causes accumulation of cis-Golgi proteins (ERGIC-53, beta-COP, GM130) in the ER-Golgi intermediate compartment, and blocks Golgi-to-ER retrograde transport, phenocopying beta-COP depletion. ArfGAP1, 2, and 3 thus have overlapping roles in regulating COPI function in Golgi-to-ER retrograde transport.","method":"siRNA triple knockdown, ARF-GTP level measurement, immunofluorescence of Golgi markers, Golgi-to-ER retrograde transport assay, electron microscopy","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean triple KD with multiple orthogonal readouts (GTP-ARF levels, marker localization, transport assay, EM), replicated findings across methods","pmids":["19299515"],"is_preprint":false},{"year":2010,"finding":"ARFGAP2 and ARFGAP3 follow the dynamic behavior of coatomer upon stimulation of vesicle budding in living cells more closely than ARFGAP1. Knockdown of both ARFGAP2 and ARFGAP3 prevents proper assembly of the COPI coat lattice and causes Golgi unstacking and cisternal shortening, whereas ARFGAP1 knockdown does not produce these effects, indicating ARFGAP2 and ARFGAP3 are key components of the COPI coat lattice necessary for proper vesicle formation.","method":"Live-cell imaging, siRNA knockdown, electron microscopy of COPI coat lattice assembly","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — live imaging with knockdown, electron microscopy, multiple orthogonal methods in single lab","pmids":["20858901"],"is_preprint":false},{"year":2011,"finding":"ARFGAP2 physically interacts with the calcium-binding protein secretagogin with high affinity (equilibrium dissociation constant 100 pM to 10 nM range), as identified by protein array screening and validated by surface plasmon resonance and GST pulldown assays.","method":"Protein array screening, surface plasmon resonance, GST pulldown assay","journal":"Molecular bioSystems","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal validation by SPR and pulldown, single lab, quantitative binding constants determined","pmids":["21528130"],"is_preprint":false},{"year":2012,"finding":"Within the CM4 (adaptin-like tetrameric) subcomplex of coatomer, ARFGAP2 interacts with a novel hydrophobic pocket on the appendage domain of gamma1-COP. CM4 (but not CM3) is recruited to membranes through Arf1 and subsequently recruits ARFGAP2. Neither CM3 nor CM4 alone stimulates ARFGAP2 activity, but both subcomplexes together are required: CM4 functions in GAP recruitment while the cage-like CM3 subcomplex stimulates ARFGAP2-dependent GTP hydrolysis on Arf1.","method":"Recombinant coatomer subcomplex reconstitution, in vitro GAP activity assays, membrane recruitment assays","journal":"Traffic","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with recombinant subcomplexes, dissection of distinct roles by functional assays, single lab with multiple orthogonal methods","pmids":["22375848"],"is_preprint":false},{"year":2015,"finding":"GIV/Girdin interacts with ArfGAP2/3 at the Golgi as part of a mechanism by which Gαi activation imposes finiteness on Arf1 GTP cycling. Selective inhibition of the GIV-Gαi pathway elevates GTP-bound Arf1 levels and delays protein transport along the secretory pathway.","method":"Co-immunoprecipitation, Arf1-GTP level measurement, secretory pathway transport assay","journal":"Developmental cell","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — Co-IP interaction shown, functional transport assay, single lab, limited mechanistic detail for ARFGAP2 specifically","pmids":["25865347"],"is_preprint":false},{"year":2015,"finding":"In yeast, Glo3 (ArfGAP2/3 orthologue) and ergosterol collaborate in transport of a subset of plasma membrane cargoes (tryptophan transporter Tat2, general amino acid permease Gap1, v-SNARE Snc1). In a glo3Δ erg3Δ double mutant, these cargoes accumulate in internal endosomal structures after endocytosis, suggesting a role for ArfGAP2/3 in recycling from endosomes.","method":"Yeast double-mutant genetic epistasis, fluorescence microscopy of cargo localization","journal":"Biology open","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — double-mutant epistasis in yeast with multiple cargo readouts, single lab","pmids":["25964658"],"is_preprint":false},{"year":2019,"finding":"In budding yeast, Glo3 (ArfGAP2/3 orthologue) specifically triggers Arf1 GTP hydrolysis that impinges on COPI coat stability. The Snf1 kinase complex (yeast AMPK homologue) phosphorylates the non-catalytic region of Glo3 that is crucial for this effect, thereby regulating Glo3 function in the COPI vesicle cycle.","method":"Genetic dissection, kinase phosphorylation assay, COPI coat stability assay in yeast","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic and biochemical dissection with defined phosphorylation, single lab","pmids":["31331965"],"is_preprint":false},{"year":2001,"finding":"ARFGAP2 (Zfp289) is a novel zinc finger protein whose mRNA expression is induced by Id-1 in mouse mammary epithelial cells. The protein is predominantly cytoplasmic as determined by GFP fusion localization, and its constitutive expression increases the S-phase index in serum-free culture, indicating a role in proliferation downstream of Id-1.","method":"Degenerate PCR cloning from Id-1-transfected cells, GFP fusion subcellular localization, S-phase index measurement by flow cytometry","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — direct localization by GFP fusion and functional proliferation assay, single lab, no pathway mechanistic detail","pmids":["11278321"],"is_preprint":false},{"year":2025,"finding":"ArfGAP2 is required for STING-mediated proton efflux from the Golgi and for non-transcriptional Golgi trafficking of protein cargos downstream of STING activation. Deletion of ArfGAP2 in hematopoietic and endothelial cells markedly reduces STING-mediated cytokine and chemokine secretion, immune cell activation, and autoinflammatory pathology in SAVI mice.","method":"Conditional knockout mice (hematopoietic/endothelial-specific), proton efflux assays, Golgi trafficking assays, cytokine secretion measurements, in vivo autoinflammatory disease model","journal":"Cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO with multiple orthogonal readouts (proton channel activity, cargo trafficking, cytokine secretion, in vivo disease model), published in high-impact journal","pmids":["39947179"],"is_preprint":false},{"year":2018,"finding":"ArfGAP2 and ArfGAP3 do not play a role in GBF1 recruitment to Golgi membranes, as determined by in vivo experiments examining Arf-GDP-regulated GBF1 recruitment.","method":"In vivo GBF1 recruitment assay with ArfGAP2/3 perturbation","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct experimental test yielding a negative result for ARFGAP2 in GBF1 recruitment, single lab","pmids":["29507113"],"is_preprint":false},{"year":2021,"finding":"ArfGAP2 does not act as a GAP for human Arl1; exogenous expression of ArfGAP2 (unlike ArfGAP1) does not cause dissociation of endogenous Arl1 from the TGN.","method":"Overexpression assay with TGN localization readout by immunofluorescence","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct negative result from overexpression experiment, single lab","pmids":["33715220"],"is_preprint":false}],"current_model":"ARFGAP2 is a coatomer-dependent ArfGAP (human orthologue of yeast Glo3) that is recruited to the Golgi via direct interaction with the gamma1-COP appendage domain of the CM4 coatomer subcomplex, where the full heptameric coatomer (requiring both CM4 and CM3 subcomplexes) stimulates its catalytic GTP hydrolysis on Arf1 to regulate COPI vesicle formation, coat lattice assembly, and Golgi-to-ER retrograde transport; additionally, ARFGAP2 acts as a cell-type-specific regulator of STING-mediated proton efflux from the Golgi and facilitates Golgi trafficking of cytokine cargos, contributing to autoinflammatory disease pathogenesis."},"narrative":{"mechanistic_narrative":"ARFGAP2 is a coatomer-dependent ArfGAP that regulates COPI vesicle formation and Golgi-to-ER retrograde transport (human orthologue of yeast Glo3) [PMID:17760859, PMID:19015319]. Unlike ArfGAP1, it does not bind membranes directly but is recruited to the Golgi through interaction with coatomer, which in turn stimulates its catalytic GTP hydrolysis on Arf1 [PMID:19015319, PMID:19109418]. Recruitment is mediated by a hydrophobic pocket on the gamma1-COP appendage domain within the CM4 (adaptin-like tetrameric) coatomer subcomplex; CM4 brings ARFGAP2 to the membrane while the cage-like CM3 subcomplex is additionally required to stimulate Arf1 GTP hydrolysis, so the full heptameric coatomer is needed for catalysis [PMID:14690497, PMID:22375848]. Functionally, ARFGAP2 acts redundantly with ARFGAP3 as a structural component of the COPI coat lattice: combined depletion increases GTP-bound Arf1, prevents proper coat lattice assembly, and causes Golgi unstacking and a block in retrograde transport [PMID:19299515, PMID:20858901]. Beyond its housekeeping COPI role, ARFGAP2 is required for STING-mediated proton efflux from the Golgi and for non-transcriptional Golgi trafficking of cytokine cargos, and its deletion attenuates STING-driven cytokine secretion and autoinflammatory pathology in SAVI mice [PMID:39947179].","teleology":[{"year":2004,"claim":"Establishing how an ArfGAP is physically docked at the Golgi, the gamma-COP appendage domain was shown to bind ARFGAP2 through a single site on its platform subdomain, defining a coatomer-based recruitment interface.","evidence":"Crystal structure of the gamma-COP appendage domain with protein-protein interaction binding assays","pmids":["14690497"],"confidence":"High","gaps":["Did not resolve whether appendage binding alone is sufficient for Golgi recruitment in cells","No measurement of effect on GAP catalysis"]},{"year":2007,"claim":"Identifying ARFGAP2/3 as human Glo3 orthologues placed them in the COPI pathway, showing Golgi/coatomer colocalization, coatomer binding outside the zinc finger, and a dominant-negative block of retrograde transport.","evidence":"Immunofluorescence, in vitro COPI vesicle generation, truncation pulldown, dominant-negative retrograde transport assay","pmids":["17760859"],"confidence":"High","gaps":["Catalytic activity not reconstituted","Functional redundancy with ARFGAP3 not addressed"]},{"year":2008,"claim":"Resolving how ARFGAP2/3 act without membrane binding, in vitro reconstitution showed they are recruited by coatomer rather than lipid, and that coatomer stimulates their Arf1 GAP activity to levels comparable to ArfGAP1.","evidence":"In vitro GAP activity assays with recombinant proteins, membrane binding and coatomer-dependent recruitment assays; domain mapping of the central basic coatomer-binding stretch","pmids":["19015319","19109418"],"confidence":"High","gaps":["Did not identify which coatomer subcomplex mediates stimulation","In vivo relevance of domain mutants not fully tested"]},{"year":2009,"claim":"Defining the minimal functional unit, yeast Glo3 genetics showed the GAP domain plus the BoCCS region — which contacts coatomer, SNAREs, and cargo — is necessary and sufficient, linking ArfGAP function to cargo and SNARE engagement.","evidence":"Yeast genetic epistasis, domain truncation/mutation, dominant-negative growth and genetic suppression assays","pmids":["19602196"],"confidence":"Medium","gaps":["Mapped in yeast; mammalian BoCCS equivalent not directly tested","Direct SNARE/cargo binding affinities not quantified"]},{"year":2009,"claim":"Demonstrating the cellular consequence of losing ArfGAP activity, triple knockdown of ArfGAP1/2/3 raised GTP-Arf levels, trapped cis-Golgi proteins in the ERGIC, and blocked retrograde transport, establishing overlapping roles in COPI function.","evidence":"siRNA triple knockdown, ARF-GTP measurement, Golgi marker immunofluorescence, retrograde transport assay, electron microscopy","pmids":["19299515"],"confidence":"High","gaps":["Could not isolate ARFGAP2-specific contribution due to redundancy","Individual single-knockdown phenotypes not resolved here"]},{"year":2010,"claim":"Distinguishing ARFGAP2/3 from ArfGAP1 functionally, live imaging and EM showed ARFGAP2/3 track coatomer dynamics and are required for COPI coat lattice assembly and Golgi cisternal integrity, casting them as structural coat components.","evidence":"Live-cell imaging, siRNA knockdown, electron microscopy of coat lattice","pmids":["20858901"],"confidence":"High","gaps":["Structural basis of lattice incorporation not resolved","Did not separate ARFGAP2 from ARFGAP3 contributions"]},{"year":2012,"claim":"Dissecting the recruitment-versus-catalysis problem, recombinant subcomplex reconstitution showed CM4 (via the gamma1-COP appendage hydrophobic pocket) recruits ARFGAP2 while CM3 is required to stimulate Arf1 GTP hydrolysis, so both halves of coatomer are needed.","evidence":"Recombinant coatomer subcomplex reconstitution, in vitro GAP activity and membrane recruitment assays","pmids":["22375848"],"confidence":"High","gaps":["Atomic structure of the ARFGAP2-coatomer-Arf1 catalytic assembly not determined","How CM3 stimulates catalysis mechanistically unresolved"]},{"year":2015,"claim":"Probing upstream regulation, GIV/Girdin was found to interact with ArfGAP2/3 at the Golgi and to impose finiteness on Arf1 GTP cycling via Galphai, linking heterotrimeric G-protein signaling to ArfGAP-controlled secretion.","evidence":"Co-immunoprecipitation, Arf1-GTP measurement, secretory transport assay","pmids":["25865347"],"confidence":"Medium","gaps":["Co-IP does not establish direct ARFGAP2 contact versus ARFGAP3","Limited mechanistic detail specific to ARFGAP2"]},{"year":2019,"claim":"Adding a post-translational regulatory layer, the yeast Snf1/AMPK complex was shown to phosphorylate the non-catalytic region of Glo3 required for Arf1 hydrolysis and COPI coat stability, linking metabolic signaling to ArfGAP activity.","evidence":"Genetic dissection, kinase phosphorylation assay, COPI coat stability assay in yeast","pmids":["31331965"],"confidence":"Medium","gaps":["Phosphosite conservation/function in mammalian ARFGAP2 not tested","Effect on catalytic rate not quantified"]},{"year":2025,"claim":"Extending ARFGAP2 beyond housekeeping trafficking, conditional knockout mice revealed it is required for STING-mediated Golgi proton efflux and trafficking of cytokine cargos, and that its loss reduces autoinflammatory pathology in SAVI.","evidence":"Hematopoietic/endothelial conditional KO mice, proton efflux assays, Golgi trafficking assays, cytokine secretion, in vivo SAVI disease model","pmids":["39947179"],"confidence":"High","gaps":["Whether this role requires ARFGAP2 GAP catalysis is not resolved","Molecular link between ARFGAP2 and the STING proton channel undefined","Cell-type specificity of the requirement not fully mapped"]},{"year":null,"claim":"How ARFGAP2's COPI catalytic role mechanistically connects to its requirement for STING-driven proton efflux and cytokine trafficking remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No structure of the ARFGAP2-coatomer-Arf1 catalytic complex","STING-pathway function not yet tied to GAP activity or coatomer dependence","ARFGAP2-specific (versus ARFGAP3) contributions in mammals remain blurred by redundancy"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[2,3,8]},{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[6]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[1,2,6]},{"term_id":"GO:0031410","term_label":"cytoplasmic vesicle","supporting_discovery_ids":[1,2]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[12]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[1,5,6]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[13]}],"complexes":["COPI coat / coatomer"],"partners":["COPA","ARF1","ARFGAP3","GIV/GIRDIN","SECRETAGOGIN"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8N6H7","full_name":"ADP-ribosylation factor GTPase-activating protein 2","aliases":["GTPase-activating protein ZNF289","Zinc finger protein 289"],"length_aa":521,"mass_kda":56.7,"function":"GTPase-activating protein (GAP) for ADP ribosylation factor 1 (ARF1). Implicated in coatomer-mediated protein transport between the Golgi complex and the endoplasmic reticulum. Hydrolysis of ARF1-bound GTP may lead to dissociation of coatomer from Golgi-derived membranes to allow fusion with target membranes","subcellular_location":"Cytoplasm; Golgi apparatus membrane","url":"https://www.uniprot.org/uniprotkb/Q8N6H7/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ARFGAP2","classification":"Not Classified","n_dependent_lines":4,"n_total_lines":1208,"dependency_fraction":0.0033112582781456954},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000149182","cell_line_id":"CID000658","localizations":[{"compartment":"golgi","grade":3},{"compartment":"vesicles","grade":3},{"compartment":"cytoplasmic","grade":1}],"interactors":[{"gene":"MAD2L1","stoichiometry":0.2},{"gene":"CLK3","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID000658","total_profiled":1310},"omim":[{"mim_id":"612439","title":"ADP-RIBOSYLATION FACTOR GTPase-ACTIVATING PROTEIN 3; ARFGAP3","url":"https://www.omim.org/entry/612439"},{"mim_id":"606908","title":"ADP-RIBOSYLATION FACTOR GTPase-ACTIVATING PROTEIN 2; ARFGAP2","url":"https://www.omim.org/entry/606908"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Golgi apparatus","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ARFGAP2"},"hgnc":{"alias_symbol":["IRZ","Zfp289","FLJ14576"],"prev_symbol":["ZNF289"]},"alphafold":{"accession":"Q8N6H7","domains":[{"cath_id":"1.10.220.150","chopping":"6-128","consensus_level":"high","plddt":96.2946,"start":6,"end":128},{"cath_id":"1.20.5","chopping":"259-293","consensus_level":"medium","plddt":80.7966,"start":259,"end":293}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8N6H7","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8N6H7-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8N6H7-F1-predicted_aligned_error_v6.png","plddt_mean":65.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ARFGAP2","jax_strain_url":"https://www.jax.org/strain/search?query=ARFGAP2"},"sequence":{"accession":"Q8N6H7","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8N6H7.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8N6H7/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8N6H7"}},"corpus_meta":[{"pmid":"11515783","id":"PMC_11515783","title":"The autonomic higher order processing nuclei of the lower brain stem are among the early targets of the Alzheimer's disease-related cytoskeletal pathology.","date":"2001","source":"Acta neuropathologica","url":"https://pubmed.ncbi.nlm.nih.gov/11515783","citation_count":76,"is_preprint":false},{"pmid":"14690497","id":"PMC_14690497","title":"Gamma-COP appendage domain - structure and function.","date":"2004","source":"Traffic (Copenhagen, Denmark)","url":"https://pubmed.ncbi.nlm.nih.gov/14690497","citation_count":70,"is_preprint":false},{"pmid":"19015319","id":"PMC_19015319","title":"Differential roles of ArfGAP1, ArfGAP2, and ArfGAP3 in COPI trafficking.","date":"2008","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/19015319","citation_count":61,"is_preprint":false},{"pmid":"17760859","id":"PMC_17760859","title":"Two human ARFGAPs associated with COP-I-coated vesicles.","date":"2007","source":"Traffic (Copenhagen, Denmark)","url":"https://pubmed.ncbi.nlm.nih.gov/17760859","citation_count":50,"is_preprint":false},{"pmid":"19109418","id":"PMC_19109418","title":"Discrete determinants in ArfGAP2/3 conferring Golgi localization and regulation by the COPI coat.","date":"2008","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/19109418","citation_count":40,"is_preprint":false},{"pmid":"25865347","id":"PMC_25865347","title":"Activation of Gαi at the Golgi by GIV/Girdin imposes finiteness in Arf1 signaling.","date":"2015","source":"Developmental cell","url":"https://pubmed.ncbi.nlm.nih.gov/25865347","citation_count":37,"is_preprint":false},{"pmid":"21528130","id":"PMC_21528130","title":"Identification of a high-affinity network of secretagogin-binding proteins involved in vesicle secretion.","date":"2011","source":"Molecular 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clinical","url":"https://pubmed.ncbi.nlm.nih.gov/11474639","citation_count":28,"is_preprint":false},{"pmid":"11278321","id":"PMC_11278321","title":"Molecular cloning and characterization of a zinc finger protein involved in Id-1-stimulated mammary epithelial cell growth.","date":"2001","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11278321","citation_count":25,"is_preprint":false},{"pmid":"24076238","id":"PMC_24076238","title":"ArfGAP3 regulates the transport of cation-independent mannose 6-phosphate receptor in the post-Golgi compartment.","date":"2013","source":"Current biology : CB","url":"https://pubmed.ncbi.nlm.nih.gov/24076238","citation_count":25,"is_preprint":false},{"pmid":"20858901","id":"PMC_20858901","title":"ARFGAP2 and ARFGAP3 are essential for COPI coat assembly on the Golgi membrane of living cells.","date":"2010","source":"The Journal of biological 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autoinflammation.","date":"2025","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/39947179","citation_count":15,"is_preprint":false},{"pmid":"31331965","id":"PMC_31331965","title":"Dissection of GTPase-activating proteins reveals functional asymmetry in the COPI coat of budding yeast.","date":"2019","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/31331965","citation_count":15,"is_preprint":false},{"pmid":"25964658","id":"PMC_25964658","title":"The ArfGAP2/3 Glo3 and ergosterol collaborate in transport of a subset of cargoes.","date":"2015","source":"Biology open","url":"https://pubmed.ncbi.nlm.nih.gov/25964658","citation_count":10,"is_preprint":false},{"pmid":"22375848","id":"PMC_22375848","title":"Distinct role of subcomplexes of the COPI coat in the regulation of ArfGAP2 activity.","date":"2012","source":"Traffic (Copenhagen, 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I. Inheritance of the Ir-Z1 and ir-Z2 loci in mice.","date":"1978","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/96178","citation_count":9,"is_preprint":false},{"pmid":"33715220","id":"PMC_33715220","title":"ArfGAP1 acts as a GTPase-activating protein for human ADP-ribosylation factor-like 1 protein.","date":"2021","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/33715220","citation_count":8,"is_preprint":false},{"pmid":"36833379","id":"PMC_36833379","title":"MIF Variant rs755622 Is Associated with Severe Crohn's Disease and Better Response to Anti-TNF Adalimumab Therapy.","date":"2023","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/36833379","citation_count":8,"is_preprint":false},{"pmid":"29507113","id":"PMC_29507113","title":"The Arf-GDP-regulated recruitment of GBF1 to Golgi membranes requires domains HDS1 and HDS2 and a Golgi-localized protein receptor.","date":"2018","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/29507113","citation_count":8,"is_preprint":false},{"pmid":"36476390","id":"PMC_36476390","title":"ArfGAP3 regulates vesicle transport and glucose uptake in myoblasts.","date":"2022","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/36476390","citation_count":7,"is_preprint":false},{"pmid":"21877276","id":"PMC_21877276","title":"Protein networks involved in vesicle fusion, transport, and storage revealed by array-based proteomics.","date":"2011","source":"Methods in molecular biology (Clifton, N.J.)","url":"https://pubmed.ncbi.nlm.nih.gov/21877276","citation_count":6,"is_preprint":false},{"pmid":"26482417","id":"PMC_26482417","title":"Integration of genome-wide association and extant brain expression QTL identifies candidate genes influencing prepulse inhibition in inbred F1 mice.","date":"2016","source":"Genes, brain, and behavior","url":"https://pubmed.ncbi.nlm.nih.gov/26482417","citation_count":6,"is_preprint":false},{"pmid":"37486921","id":"PMC_37486921","title":"DeepGenePrior: A deep learning model for prioritizing genes affected by copy number variants.","date":"2023","source":"PLoS computational biology","url":"https://pubmed.ncbi.nlm.nih.gov/37486921","citation_count":3,"is_preprint":false},{"pmid":"27437397","id":"PMC_27437397","title":"DASAF: An R Package for Deep Sequencing-Based Detection of Fetal Autosomal Abnormalities from Maternal Cell-Free DNA.","date":"2016","source":"BioMed research international","url":"https://pubmed.ncbi.nlm.nih.gov/27437397","citation_count":3,"is_preprint":false},{"pmid":"40019803","id":"PMC_40019803","title":"Rac1 Suppression by the Focal Adhesion Protein GIT ArfGAP2 and Podocyte Protection.","date":"2025","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/40019803","citation_count":2,"is_preprint":false},{"pmid":"38516642","id":"PMC_38516642","title":"Label-free quantitative proteomics reveals the mechanisms of Aurora kinase B in renal cell carcinoma.","date":"2024","source":"SAGE open medicine","url":"https://pubmed.ncbi.nlm.nih.gov/38516642","citation_count":2,"is_preprint":false},{"pmid":"40138104","id":"PMC_40138104","title":"Targets and Potential Mechanism of Chondroitin Sulfate A-selenium Nanoparticle on Kashin-Beck Disease Chondrocytes.","date":"2025","source":"Biological trace element research","url":"https://pubmed.ncbi.nlm.nih.gov/40138104","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":17749,"output_tokens":4138,"usd":0.057659,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11893,"output_tokens":3699,"usd":0.07597,"stage2_stop_reason":"end_turn"},"total_usd":0.133629,"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\": 2004,\n      \"finding\": \"The appendage domain of gamma-COP binds to ARFGAP2 (mammalian Glo3p orthologue) via a single protein-protein interaction site on its platform subdomain, analogous to the alpha-appendage of AP2.\",\n      \"method\": \"Crystal structure of gamma-COP appendage domain combined with protein-protein interaction binding assays\",\n      \"journal\": \"Traffic\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structure with functional validation of interaction site, single lab but orthogonal structural and binding methods\",\n      \"pmids\": [\"14690497\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"ARFGAP2 and ARFGAP3 are human orthologues of yeast Glo3p; ARFGAP2 localizes to the Golgi complex and peripheral punctate structures colocalizing with coatomer subunits, is associated with COP-I-coated vesicles generated in vitro, and directly binds coatomer via a region outside its zinc finger domain. Expression of a truncated ARFGAP2 lacking its zinc finger domain (DeltaN-ARFGAP2) inhibits COP-I-dependent Golgi-to-ER transport of cholera toxin in vivo.\",\n      \"method\": \"Immunofluorescence colocalization, in vitro COP-I vesicle generation assay, pulldown binding assay with truncation mutant, dominant-negative inhibition of retrograde transport in vivo\",\n      \"journal\": \"Traffic\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (IF, in vitro vesicle assay, pulldown, in vivo transport assay) in single lab\",\n      \"pmids\": [\"17760859\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Unlike ArfGAP1, ARFGAP2 and ARFGAP3 do not bind directly to membranes but are recruited to the Golgi via interactions with coatomer. In the presence of coatomer, ARFGAP2 and ARFGAP3 GAP activities are comparable to or higher than ArfGAP1 activity, establishing that coatomer functions to stimulate ARFGAP2/3-catalyzed GTP hydrolysis on Arf1.\",\n      \"method\": \"In vitro GAP activity assays with recombinant proteins, membrane binding assays, coatomer-dependent recruitment assays\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution of GAP activity with recombinant proteins and defined conditions, single lab with multiple orthogonal assays\",\n      \"pmids\": [\"19015319\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"The Golgi localization and catalytic activity of ARFGAP2/3 depends on coatomer interaction. A central basic stretch in ARFGAP3 interacts directly with coatomer and is essential for ArfGAP3 catalytic activity on Arf1-GTP, while a carboxy-amphipathic motif interacts directly with lipid membranes but plays only a minor role in regulating GAP activity.\",\n      \"method\": \"Reporter fusion Golgi localization assay, in vitro GAP activity assays, direct binding assays between isolated domains and coatomer or lipid membranes\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with domain mapping, multiple orthogonal methods, single lab\",\n      \"pmids\": [\"19109418\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The GAP domain together with the BoCCS (binding of coatomer, cargo, and SNAREs) region of yeast Glo3 (ArfGAP2/3 orthologue) is necessary and sufficient for all vital Glo3 functions. The BoCCS region interacts with coatomer, SNAREs, and cargo. A truncated Glo3 lacking the GAP domain acts as a dominant negative whose phenotype is alleviated by mutating the BoCCS region or the Glo3 regulatory motif (GRM), or by overexpression of ER-Golgi SNAREs.\",\n      \"method\": \"Yeast genetic epistasis, domain truncation/mutation analysis, dominant negative growth assay, genetic suppression\",\n      \"journal\": \"Traffic\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — yeast epistasis and genetic suppression with multiple domain mutants, single lab\",\n      \"pmids\": [\"19602196\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Simultaneous knockdown of ArfGAP1, ArfGAP2, and ArfGAP3 in mammalian cells increases GTP-bound ARF levels, causes accumulation of cis-Golgi proteins (ERGIC-53, beta-COP, GM130) in the ER-Golgi intermediate compartment, and blocks Golgi-to-ER retrograde transport, phenocopying beta-COP depletion. ArfGAP1, 2, and 3 thus have overlapping roles in regulating COPI function in Golgi-to-ER retrograde transport.\",\n      \"method\": \"siRNA triple knockdown, ARF-GTP level measurement, immunofluorescence of Golgi markers, Golgi-to-ER retrograde transport assay, electron microscopy\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean triple KD with multiple orthogonal readouts (GTP-ARF levels, marker localization, transport assay, EM), replicated findings across methods\",\n      \"pmids\": [\"19299515\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"ARFGAP2 and ARFGAP3 follow the dynamic behavior of coatomer upon stimulation of vesicle budding in living cells more closely than ARFGAP1. Knockdown of both ARFGAP2 and ARFGAP3 prevents proper assembly of the COPI coat lattice and causes Golgi unstacking and cisternal shortening, whereas ARFGAP1 knockdown does not produce these effects, indicating ARFGAP2 and ARFGAP3 are key components of the COPI coat lattice necessary for proper vesicle formation.\",\n      \"method\": \"Live-cell imaging, siRNA knockdown, electron microscopy of COPI coat lattice assembly\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging with knockdown, electron microscopy, multiple orthogonal methods in single lab\",\n      \"pmids\": [\"20858901\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"ARFGAP2 physically interacts with the calcium-binding protein secretagogin with high affinity (equilibrium dissociation constant 100 pM to 10 nM range), as identified by protein array screening and validated by surface plasmon resonance and GST pulldown assays.\",\n      \"method\": \"Protein array screening, surface plasmon resonance, GST pulldown assay\",\n      \"journal\": \"Molecular bioSystems\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal validation by SPR and pulldown, single lab, quantitative binding constants determined\",\n      \"pmids\": [\"21528130\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Within the CM4 (adaptin-like tetrameric) subcomplex of coatomer, ARFGAP2 interacts with a novel hydrophobic pocket on the appendage domain of gamma1-COP. CM4 (but not CM3) is recruited to membranes through Arf1 and subsequently recruits ARFGAP2. Neither CM3 nor CM4 alone stimulates ARFGAP2 activity, but both subcomplexes together are required: CM4 functions in GAP recruitment while the cage-like CM3 subcomplex stimulates ARFGAP2-dependent GTP hydrolysis on Arf1.\",\n      \"method\": \"Recombinant coatomer subcomplex reconstitution, in vitro GAP activity assays, membrane recruitment assays\",\n      \"journal\": \"Traffic\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with recombinant subcomplexes, dissection of distinct roles by functional assays, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"22375848\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"GIV/Girdin interacts with ArfGAP2/3 at the Golgi as part of a mechanism by which Gαi activation imposes finiteness on Arf1 GTP cycling. Selective inhibition of the GIV-Gαi pathway elevates GTP-bound Arf1 levels and delays protein transport along the secretory pathway.\",\n      \"method\": \"Co-immunoprecipitation, Arf1-GTP level measurement, secretory pathway transport assay\",\n      \"journal\": \"Developmental cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — Co-IP interaction shown, functional transport assay, single lab, limited mechanistic detail for ARFGAP2 specifically\",\n      \"pmids\": [\"25865347\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"In yeast, Glo3 (ArfGAP2/3 orthologue) and ergosterol collaborate in transport of a subset of plasma membrane cargoes (tryptophan transporter Tat2, general amino acid permease Gap1, v-SNARE Snc1). In a glo3Δ erg3Δ double mutant, these cargoes accumulate in internal endosomal structures after endocytosis, suggesting a role for ArfGAP2/3 in recycling from endosomes.\",\n      \"method\": \"Yeast double-mutant genetic epistasis, fluorescence microscopy of cargo localization\",\n      \"journal\": \"Biology open\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — double-mutant epistasis in yeast with multiple cargo readouts, single lab\",\n      \"pmids\": [\"25964658\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"In budding yeast, Glo3 (ArfGAP2/3 orthologue) specifically triggers Arf1 GTP hydrolysis that impinges on COPI coat stability. The Snf1 kinase complex (yeast AMPK homologue) phosphorylates the non-catalytic region of Glo3 that is crucial for this effect, thereby regulating Glo3 function in the COPI vesicle cycle.\",\n      \"method\": \"Genetic dissection, kinase phosphorylation assay, COPI coat stability assay in yeast\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic and biochemical dissection with defined phosphorylation, single lab\",\n      \"pmids\": [\"31331965\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"ARFGAP2 (Zfp289) is a novel zinc finger protein whose mRNA expression is induced by Id-1 in mouse mammary epithelial cells. The protein is predominantly cytoplasmic as determined by GFP fusion localization, and its constitutive expression increases the S-phase index in serum-free culture, indicating a role in proliferation downstream of Id-1.\",\n      \"method\": \"Degenerate PCR cloning from Id-1-transfected cells, GFP fusion subcellular localization, S-phase index measurement by flow cytometry\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — direct localization by GFP fusion and functional proliferation assay, single lab, no pathway mechanistic detail\",\n      \"pmids\": [\"11278321\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ArfGAP2 is required for STING-mediated proton efflux from the Golgi and for non-transcriptional Golgi trafficking of protein cargos downstream of STING activation. Deletion of ArfGAP2 in hematopoietic and endothelial cells markedly reduces STING-mediated cytokine and chemokine secretion, immune cell activation, and autoinflammatory pathology in SAVI mice.\",\n      \"method\": \"Conditional knockout mice (hematopoietic/endothelial-specific), proton efflux assays, Golgi trafficking assays, cytokine secretion measurements, in vivo autoinflammatory disease model\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO with multiple orthogonal readouts (proton channel activity, cargo trafficking, cytokine secretion, in vivo disease model), published in high-impact journal\",\n      \"pmids\": [\"39947179\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"ArfGAP2 and ArfGAP3 do not play a role in GBF1 recruitment to Golgi membranes, as determined by in vivo experiments examining Arf-GDP-regulated GBF1 recruitment.\",\n      \"method\": \"In vivo GBF1 recruitment assay with ArfGAP2/3 perturbation\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct experimental test yielding a negative result for ARFGAP2 in GBF1 recruitment, single lab\",\n      \"pmids\": [\"29507113\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ArfGAP2 does not act as a GAP for human Arl1; exogenous expression of ArfGAP2 (unlike ArfGAP1) does not cause dissociation of endogenous Arl1 from the TGN.\",\n      \"method\": \"Overexpression assay with TGN localization readout by immunofluorescence\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct negative result from overexpression experiment, single lab\",\n      \"pmids\": [\"33715220\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ARFGAP2 is a coatomer-dependent ArfGAP (human orthologue of yeast Glo3) that is recruited to the Golgi via direct interaction with the gamma1-COP appendage domain of the CM4 coatomer subcomplex, where the full heptameric coatomer (requiring both CM4 and CM3 subcomplexes) stimulates its catalytic GTP hydrolysis on Arf1 to regulate COPI vesicle formation, coat lattice assembly, and Golgi-to-ER retrograde transport; additionally, ARFGAP2 acts as a cell-type-specific regulator of STING-mediated proton efflux from the Golgi and facilitates Golgi trafficking of cytokine cargos, contributing to autoinflammatory disease pathogenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ARFGAP2 is a coatomer-dependent ArfGAP that regulates COPI vesicle formation and Golgi-to-ER retrograde transport (human orthologue of yeast Glo3) [#1, #2]. Unlike ArfGAP1, it does not bind membranes directly but is recruited to the Golgi through interaction with coatomer, which in turn stimulates its catalytic GTP hydrolysis on Arf1 [#2, #3]. Recruitment is mediated by a hydrophobic pocket on the gamma1-COP appendage domain within the CM4 (adaptin-like tetrameric) coatomer subcomplex; CM4 brings ARFGAP2 to the membrane while the cage-like CM3 subcomplex is additionally required to stimulate Arf1 GTP hydrolysis, so the full heptameric coatomer is needed for catalysis [#0, #8]. Functionally, ARFGAP2 acts redundantly with ARFGAP3 as a structural component of the COPI coat lattice: combined depletion increases GTP-bound Arf1, prevents proper coat lattice assembly, and causes Golgi unstacking and a block in retrograde transport [#5, #6]. Beyond its housekeeping COPI role, ARFGAP2 is required for STING-mediated proton efflux from the Golgi and for non-transcriptional Golgi trafficking of cytokine cargos, and its deletion attenuates STING-driven cytokine secretion and autoinflammatory pathology in SAVI mice [#13].\",\n  \"teleology\": [\n    {\n      \"year\": 2004,\n      \"claim\": \"Establishing how an ArfGAP is physically docked at the Golgi, the gamma-COP appendage domain was shown to bind ARFGAP2 through a single site on its platform subdomain, defining a coatomer-based recruitment interface.\",\n      \"evidence\": \"Crystal structure of the gamma-COP appendage domain with protein-protein interaction binding assays\",\n      \"pmids\": [\"14690497\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve whether appendage binding alone is sufficient for Golgi recruitment in cells\", \"No measurement of effect on GAP catalysis\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Identifying ARFGAP2/3 as human Glo3 orthologues placed them in the COPI pathway, showing Golgi/coatomer colocalization, coatomer binding outside the zinc finger, and a dominant-negative block of retrograde transport.\",\n      \"evidence\": \"Immunofluorescence, in vitro COPI vesicle generation, truncation pulldown, dominant-negative retrograde transport assay\",\n      \"pmids\": [\"17760859\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Catalytic activity not reconstituted\", \"Functional redundancy with ARFGAP3 not addressed\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Resolving how ARFGAP2/3 act without membrane binding, in vitro reconstitution showed they are recruited by coatomer rather than lipid, and that coatomer stimulates their Arf1 GAP activity to levels comparable to ArfGAP1.\",\n      \"evidence\": \"In vitro GAP activity assays with recombinant proteins, membrane binding and coatomer-dependent recruitment assays; domain mapping of the central basic coatomer-binding stretch\",\n      \"pmids\": [\"19015319\", \"19109418\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify which coatomer subcomplex mediates stimulation\", \"In vivo relevance of domain mutants not fully tested\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Defining the minimal functional unit, yeast Glo3 genetics showed the GAP domain plus the BoCCS region — which contacts coatomer, SNAREs, and cargo — is necessary and sufficient, linking ArfGAP function to cargo and SNARE engagement.\",\n      \"evidence\": \"Yeast genetic epistasis, domain truncation/mutation, dominant-negative growth and genetic suppression assays\",\n      \"pmids\": [\"19602196\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mapped in yeast; mammalian BoCCS equivalent not directly tested\", \"Direct SNARE/cargo binding affinities not quantified\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Demonstrating the cellular consequence of losing ArfGAP activity, triple knockdown of ArfGAP1/2/3 raised GTP-Arf levels, trapped cis-Golgi proteins in the ERGIC, and blocked retrograde transport, establishing overlapping roles in COPI function.\",\n      \"evidence\": \"siRNA triple knockdown, ARF-GTP measurement, Golgi marker immunofluorescence, retrograde transport assay, electron microscopy\",\n      \"pmids\": [\"19299515\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Could not isolate ARFGAP2-specific contribution due to redundancy\", \"Individual single-knockdown phenotypes not resolved here\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Distinguishing ARFGAP2/3 from ArfGAP1 functionally, live imaging and EM showed ARFGAP2/3 track coatomer dynamics and are required for COPI coat lattice assembly and Golgi cisternal integrity, casting them as structural coat components.\",\n      \"evidence\": \"Live-cell imaging, siRNA knockdown, electron microscopy of coat lattice\",\n      \"pmids\": [\"20858901\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of lattice incorporation not resolved\", \"Did not separate ARFGAP2 from ARFGAP3 contributions\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Dissecting the recruitment-versus-catalysis problem, recombinant subcomplex reconstitution showed CM4 (via the gamma1-COP appendage hydrophobic pocket) recruits ARFGAP2 while CM3 is required to stimulate Arf1 GTP hydrolysis, so both halves of coatomer are needed.\",\n      \"evidence\": \"Recombinant coatomer subcomplex reconstitution, in vitro GAP activity and membrane recruitment assays\",\n      \"pmids\": [\"22375848\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Atomic structure of the ARFGAP2-coatomer-Arf1 catalytic assembly not determined\", \"How CM3 stimulates catalysis mechanistically unresolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Probing upstream regulation, GIV/Girdin was found to interact with ArfGAP2/3 at the Golgi and to impose finiteness on Arf1 GTP cycling via Galphai, linking heterotrimeric G-protein signaling to ArfGAP-controlled secretion.\",\n      \"evidence\": \"Co-immunoprecipitation, Arf1-GTP measurement, secretory transport assay\",\n      \"pmids\": [\"25865347\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Co-IP does not establish direct ARFGAP2 contact versus ARFGAP3\", \"Limited mechanistic detail specific to ARFGAP2\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Adding a post-translational regulatory layer, the yeast Snf1/AMPK complex was shown to phosphorylate the non-catalytic region of Glo3 required for Arf1 hydrolysis and COPI coat stability, linking metabolic signaling to ArfGAP activity.\",\n      \"evidence\": \"Genetic dissection, kinase phosphorylation assay, COPI coat stability assay in yeast\",\n      \"pmids\": [\"31331965\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Phosphosite conservation/function in mammalian ARFGAP2 not tested\", \"Effect on catalytic rate not quantified\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Extending ARFGAP2 beyond housekeeping trafficking, conditional knockout mice revealed it is required for STING-mediated Golgi proton efflux and trafficking of cytokine cargos, and that its loss reduces autoinflammatory pathology in SAVI.\",\n      \"evidence\": \"Hematopoietic/endothelial conditional KO mice, proton efflux assays, Golgi trafficking assays, cytokine secretion, in vivo SAVI disease model\",\n      \"pmids\": [\"39947179\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether this role requires ARFGAP2 GAP catalysis is not resolved\", \"Molecular link between ARFGAP2 and the STING proton channel undefined\", \"Cell-type specificity of the requirement not fully mapped\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ARFGAP2's COPI catalytic role mechanistically connects to its requirement for STING-driven proton efflux and cytokine trafficking remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No structure of the ARFGAP2-coatomer-Arf1 catalytic complex\", \"STING-pathway function not yet tied to GAP activity or coatomer dependence\", \"ARFGAP2-specific (versus ARFGAP3) contributions in mammals remain blurred by redundancy\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [2, 3, 8]},\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [1, 2, 6]},\n      {\"term_id\": \"GO:0031410\", \"supporting_discovery_ids\": [1, 2]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [12]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [1, 5, 6]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [13]}\n    ],\n    \"complexes\": [\n      \"COPI coat / coatomer\"\n    ],\n    \"partners\": [\n      \"COPA\",\n      \"ARF1\",\n      \"ARFGAP3\",\n      \"GIV/Girdin\",\n      \"secretagogin\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}