{"gene":"ARMH3","run_date":"2026-06-09T22:02:44","timeline":{"discoveries":[{"year":2024,"finding":"ARMH3 (C10orf76) binds to active (GTP-bound) but not inactive ARL5, and is recruited to the trans-Golgi network (TGN) in a SYS1-ARFRP1-ARL5-dependent manner, functioning as an ARL5 effector.","method":"Proximity biotinylation (BioID) and protein interaction assays; recruitment dependency established by genetic manipulation of SYS1-ARFRP1-ARL5 pathway","journal":"Nature Communications","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal protein interaction assays with genetic epistasis demonstrating GTP-dependence and pathway placement, single lab with multiple orthogonal methods","pmids":["39580461"],"is_preprint":false},{"year":2024,"finding":"ARMH3, recruited to the TGN via the SYS1-ARFRP1-ARL5 axis, activates PI4KB (phosphatidylinositol 4-kinase IIIβ) to generate the main pool of PI4P at the TGN, which in turn contributes to recruitment of the oncoprotein GOLPH3 and glycan modifications at the TGN.","method":"Loss-of-function (KD/KO) with PI4P level measurements at TGN, GOLPH3 localization assay, glycan modification readout","journal":"Nature Communications","confidence":"High","confidence_rationale":"Tier 2 / Moderate — clean KO/KD with defined cellular phenotypes (PI4P levels, GOLPH3 recruitment, glycan modifications) and pathway placement, single lab but multiple orthogonal readouts","pmids":["39580461"],"is_preprint":false},{"year":2024,"finding":"ARMH3 (DGARM/C10orf76) is not required for retrograde transport of various cargo proteins from endosomes to the TGN, distinguishing its function from that of GARP.","method":"Loss-of-function (KO) with retrograde cargo trafficking assay — negative result","journal":"Nature Communications","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean KO with defined trafficking readout, single lab, single method; negative finding","pmids":["39580461"],"is_preprint":false},{"year":2023,"finding":"Upon cGAMP stimulation, ARMH3 interacts with STING at the Golgi and recruits PI4KB to synthesize PI4P, which directs STING Golgi-to-endosome trafficking via the PI4P-binding proteins AP-1 and GGA2.","method":"Genome-wide CRISPR-Cas9 screen to identify ARMH3; co-immunoprecipitation to confirm ARMH3-STING interaction; RNAi knockdown of PI4P-binding proteins; PI4P level measurements; STING trafficking assays","journal":"Immunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — genome-wide screen + Co-IP + functional RNAi knockdowns + in vivo mouse model (Armh3fl/fl;LyzCre mice), multiple orthogonal methods","pmids":["36921576"],"is_preprint":false},{"year":2023,"finding":"Disruption of the ARMH3-PI4KB-PI4P axis impairs STING activation, while aberrantly elevated cellular PI4P leads to cGAS-independent STING activation, and Armh3fl/fl;LyzCre/Cre mice are susceptible to DNA virus challenge in vivo.","method":"RNAi knockdown of PI4P-binding proteins; pharmacological manipulation of cellular PI4P levels; conditional knockout mouse model challenged with DNA virus","journal":"Immunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal approaches including in vivo mouse genetics and pharmacological manipulation, replicated across methods within same study","pmids":["36921576"],"is_preprint":false},{"year":2019,"finding":"C10orf76 (ARMH3) directly binds PI4KB via the kinase linker region of PI4KB, forming a heterodimeric complex whose assembly is modulated by PKA-dependent phosphorylation of PI4KB.","method":"Hydrogen-deuterium exchange mass spectrometry (HDX-MS); complex-disrupting mutagenesis; biochemical binding assays","journal":"EMBO Reports","confidence":"High","confidence_rationale":"Tier 1 / Moderate — HDX-MS structural characterization with mutagenesis validating binding interface, single lab but multiple orthogonal methods","pmids":["31829496"],"is_preprint":false},{"year":2019,"finding":"PI4KB is required for membrane recruitment of C10orf76 (ARMH3) to the Golgi, and an intact C10orf76-PI4KB complex is required for Golgi PI4P levels and replication of c10orf76-dependent enteroviruses (e.g., coxsackievirus A10).","method":"Complex-disrupting mutations; PI4P level measurements at Golgi; viral replication assays; subcellular localization by fluorescence microscopy","journal":"EMBO Reports","confidence":"High","confidence_rationale":"Tier 2 / Moderate — mutagenesis combined with PI4P measurements, localization, and functional viral replication readout, multiple orthogonal methods in one study","pmids":["31829496"],"is_preprint":false},{"year":2019,"finding":"C10orf76 (ARMH3) contributes to proper Arf1 activation at the Golgi, providing a putative mechanism for the C10orf76-dependent increase in PI4P levels.","method":"Knockdown with Arf1 activation assay","journal":"EMBO Reports","confidence":"Medium","confidence_rationale":"Tier 3 / Weak — single knockdown assay, single lab, single method, described as 'putative mechanism'","pmids":["31829496"],"is_preprint":false},{"year":2019,"finding":"C10orf76 (ARMH3) interacts with GBF1 (a Golgi-localized ARF guanine nucleotide exchange factor) and rapidly cycles on and off GBF1-positive Golgi structures; its depletion causes Golgi fragmentation, alters GBF1 recruitment, and impairs secretion.","method":"BioID proximity biotinylation from Golgi-enriched fractions; co-immunoprecipitation; live-cell imaging; RNAi knockdown with Golgi morphology and secretion readouts","journal":"Molecular & Cellular Proteomics","confidence":"High","confidence_rationale":"Tier 2 / Moderate — BioID + Co-IP + live imaging + functional knockdown phenotypes, multiple orthogonal methods in single study","pmids":["31519766"],"is_preprint":false},{"year":2023,"finding":"C10orf76 (ARMH3) localizes predominantly at distal Golgi regions and, together with PI4KB, generates a PI4P pool that is preferentially utilized by the ceramide transport protein CERT for ER-to-distal-Golgi ceramide trafficking (as opposed to the PI4KB pool recruited by ACBD3).","method":"Genome-wide screening; super-resolution microscopy; knockdown/knockout of PI4KB, ACBD3, and C10orf76 with ceramide trafficking assays","journal":"Journal of Cell Biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — genome-wide screen + super-resolution localization + functional KO/KD with specific lipid trafficking readout, multiple orthogonal methods in one study","pmids":["37195633"],"is_preprint":false}],"current_model":"ARMH3 (C10orf76/DGARM) is an armadillo-repeat protein that localizes to the trans-Golgi network (TGN) as an effector of the active GTPase ARL5 (recruited via the SYS1-ARFRP1-ARL5 axis), where it binds PI4KB through its kinase linker region (modulated by PKA phosphorylation) to generate PI4P at the TGN; this PI4P pool drives multiple downstream processes including STING Golgi-to-endosome trafficking and antiviral signaling (via AP-1/GGA2), CERT-mediated ceramide transport at ER-distal Golgi membrane contact sites, GOLPH3 recruitment, glycan modifications, and enterovirus replication organelle formation, while also contributing to Golgi maintenance and secretion through interactions with GBF1 and regulation of Arf1 activation."},"narrative":{"mechanistic_narrative":"ARMH3 (C10orf76/DGARM) is an armadillo-repeat protein that organizes phosphatidylinositol 4-phosphate (PI4P) production at the trans-Golgi network to drive downstream membrane trafficking, lipid transport, and innate immune signaling [PMID:39580461, PMID:36921576]. It is recruited to the TGN as an effector of the active GTPase ARL5, binding GTP-bound but not inactive ARL5 in a SYS1-ARFRP1-ARL5-dependent manner [PMID:39580461]. At the Golgi, ARMH3 forms a heterodimeric complex with PI4KB by binding the PI4KB kinase linker region, an interaction modulated by PKA-dependent phosphorylation of PI4KB; this complex is required both for ARMH3 membrane recruitment and for Golgi PI4P levels [PMID:31829496]. Through this PI4KB-dependent PI4P pool, ARMH3 promotes recruitment of the oncoprotein GOLPH3 and TGN glycan modifications [PMID:39580461], and supplies a distal-Golgi PI4P pool preferentially used by the ceramide transport protein CERT for ER-to-Golgi ceramide trafficking [PMID:37195633]. In innate immunity, ARMH3 interacts with STING at the Golgi upon cGAMP stimulation and recruits PI4KB to generate PI4P that directs STING Golgi-to-endosome trafficking via AP-1 and GGA2; disruption of the ARMH3-PI4KB-PI4P axis impairs STING activation, and Armh3-deficient mice are susceptible to DNA virus challenge [PMID:36921576]. ARMH3 also interacts with the ARF GEF GBF1 and contributes to Arf1 activation, with its depletion causing Golgi fragmentation and impaired secretion [PMID:31829496, PMID:31519766], while its function is distinct from GARP-mediated endosome-to-TGN retrograde transport [PMID:39580461].","teleology":[{"year":2019,"claim":"Established the core biochemical interaction underlying ARMH3 function: that it directly binds and partners PI4KB, defining the molecular basis for its role in Golgi PI4P generation.","evidence":"HDX-MS, complex-disrupting mutagenesis, and biochemical binding assays mapping the PI4KB kinase linker interface and PKA-phosphorylation modulation","pmids":["31829496"],"confidence":"High","gaps":["No high-resolution structure of the heterodimer","Functional consequence of PKA-modulated assembly on PI4P output not quantified"]},{"year":2019,"claim":"Showed the ARMH3-PI4KB complex is functionally required, linking complex integrity to Golgi PI4P levels, ARMH3 membrane recruitment, and enterovirus replication.","evidence":"Complex-disrupting mutations with Golgi PI4P measurements, localization microscopy, and viral replication assays","pmids":["31829496"],"confidence":"High","gaps":["Mechanism by which PI4KB recruits ARMH3 to membranes not resolved","Range of enteroviruses dependent on ARMH3 incompletely defined"]},{"year":2019,"claim":"Placed ARMH3 in Golgi maintenance machinery by linking it to GBF1 and Arf1 activation, providing a candidate mechanism for its effect on PI4P and secretion.","evidence":"BioID, Co-IP, live-cell imaging, and RNAi knockdown with Golgi morphology, secretion, and Arf1 activation readouts","pmids":["31519766","31829496"],"confidence":"Medium","gaps":["Arf1 activation effect supported by a single knockdown assay described as putative","Direct vs indirect nature of the GBF1-ARMH3 interaction not dissected"]},{"year":2023,"claim":"Connected the ARMH3-PI4KB-PI4P axis to innate immunity, showing ARMH3 controls STING Golgi-to-endosome trafficking and antiviral defense in vivo.","evidence":"Genome-wide CRISPR screen, ARMH3-STING Co-IP, RNAi of PI4P-binding adaptors, PI4P measurements, STING trafficking assays, and Armh3fl/fl;LyzCre mice challenged with DNA virus","pmids":["36921576"],"confidence":"High","gaps":["Whether STING binding is direct or PI4P-mediated not fully separated","Spatial coupling of ARMH3-STING engagement to ARL5 recruitment unaddressed"]},{"year":2023,"claim":"Demonstrated that ARMH3 generates a spatially distinct distal-Golgi PI4P pool dedicated to CERT-mediated ceramide transport, distinguishing it from the ACBD3-recruited PI4KB pool.","evidence":"Genome-wide screening, super-resolution microscopy, and KO/KD of PI4KB, ACBD3, and C10orf76 with ceramide trafficking assays","pmids":["37195633"],"confidence":"High","gaps":["Molecular basis for spatial segregation of PI4P pools unresolved","How CERT preferentially reads the ARMH3-dependent pool not defined"]},{"year":2024,"claim":"Defined the upstream recruitment logic, establishing ARMH3 as a GTP-dependent ARL5 effector whose TGN localization drives the dominant TGN PI4P pool and downstream GOLPH3/glycosylation, while excluding a GARP-like retrograde role.","evidence":"BioID, GTP-dependent interaction and genetic epistasis through SYS1-ARFRP1-ARL5, plus KO with PI4P, GOLPH3, glycan, and retrograde cargo readouts","pmids":["39580461"],"confidence":"High","gaps":["How ARL5-dependent recruitment integrates with PI4KB-dependent recruitment not reconciled","Direct effect on glycan-modifying enzymes vs indirect PI4P effect unclear"]},{"year":null,"claim":"How ARMH3 spatially and temporally coordinates its distinct PI4P-dependent outputs (STING trafficking, CERT ceramide transport, GOLPH3 recruitment, glycosylation, enterovirus replication) from a single PI4KB-binding activity remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No structural model integrating ARL5, GBF1, and PI4KB engagement","Mechanism partitioning PI4P pools between competing effectors unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[1,3,5,6]},{"term_id":"GO:0060089","term_label":"molecular transducer activity","supporting_discovery_ids":[0]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[0,6,8,9]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[3,9]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[3,4]},{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[1,9]}],"complexes":["C10orf76-PI4KB heterodimer"],"partners":["PI4KB","ARL5","STING1","GBF1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q5T2E6","full_name":"Armadillo-like helical domain-containing protein 3","aliases":[],"length_aa":689,"mass_kda":78.7,"function":"Involved in GBF1 recruitment, Golgi maintenance and protein secretion","subcellular_location":"Golgi apparatus membrane; Cytoplasm","url":"https://www.uniprot.org/uniprotkb/Q5T2E6/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ARMH3","classification":"Not Classified","n_dependent_lines":99,"n_total_lines":1208,"dependency_fraction":0.08195364238410596},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ARMH3","total_profiled":1310},"omim":[{"mim_id":"620867","title":"ARMADILLO-LIKE HELICAL DOMAIN-CONTAINING PROTEIN 3; ARMH3","url":"https://www.omim.org/entry/620867"},{"mim_id":"612374","title":"STIMULATOR OF INTERFERON RESPONSE cGAMP INTERACTOR 1; STING1","url":"https://www.omim.org/entry/612374"},{"mim_id":"606809","title":"ACYL-CoA-BINDING DOMAIN-CONTAINING PROTEIN 3; ACBD3","url":"https://www.omim.org/entry/606809"},{"mim_id":"602758","title":"PHOSPHATIDYLINOSITOL 4-KINASE, BETA; PI4KB","url":"https://www.omim.org/entry/602758"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Vesicles","reliability":"Approved"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ARMH3"},"hgnc":{"alias_symbol":["FLJ13114","DGARM"],"prev_symbol":["C10orf76"]},"alphafold":{"accession":"Q5T2E6","domains":[{"cath_id":"-","chopping":"492-648","consensus_level":"medium","plddt":94.8822,"start":492,"end":648},{"cath_id":"1.25.40","chopping":"23-185_660-687","consensus_level":"high","plddt":87.3373,"start":23,"end":687}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q5T2E6","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q5T2E6-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q5T2E6-F1-predicted_aligned_error_v6.png","plddt_mean":84.25},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ARMH3","jax_strain_url":"https://www.jax.org/strain/search?query=ARMH3"},"sequence":{"accession":"Q5T2E6","fasta_url":"https://rest.uniprot.org/uniprotkb/Q5T2E6.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q5T2E6/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q5T2E6"}},"corpus_meta":[{"pmid":"36921576","id":"PMC_36921576","title":"ARMH3-mediated recruitment of PI4KB directs Golgi-to-endosome trafficking and activation of the antiviral effector STING.","date":"2023","source":"Immunity","url":"https://pubmed.ncbi.nlm.nih.gov/36921576","citation_count":80,"is_preprint":false},{"pmid":"35579216","id":"PMC_35579216","title":"Molecular mechanisms of PI4K regulation and their involvement in viral replication.","date":"2022","source":"Traffic (Copenhagen, Denmark)","url":"https://pubmed.ncbi.nlm.nih.gov/35579216","citation_count":38,"is_preprint":false},{"pmid":"31829496","id":"PMC_31829496","title":"Characterization of the c10orf76-PI4KB complex and its necessity for Golgi PI4P levels and enterovirus replication.","date":"2019","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/31829496","citation_count":36,"is_preprint":false},{"pmid":"17959645","id":"PMC_17959645","title":"An RNA targeted to the HIV-1 LTR promoter modulates indiscriminate off-target gene activation.","date":"2007","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/17959645","citation_count":36,"is_preprint":false},{"pmid":"31519766","id":"PMC_31519766","title":"BioID Performed on Golgi Enriched Fractions Identify C10orf76 as a GBF1 Binding Protein Essential for Golgi Maintenance and Secretion.","date":"2019","source":"Molecular & cellular proteomics : MCP","url":"https://pubmed.ncbi.nlm.nih.gov/31519766","citation_count":23,"is_preprint":false},{"pmid":"37195633","id":"PMC_37195633","title":"The C10orf76-PI4KB axis orchestrates CERT-mediated ceramide trafficking to the distal Golgi.","date":"2023","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/37195633","citation_count":14,"is_preprint":false},{"pmid":"37107618","id":"PMC_37107618","title":"Genomic Regions Associated with Milk Composition and Fertility Traits in Spring-Calved Dairy Cows in New Zealand.","date":"2023","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/37107618","citation_count":12,"is_preprint":false},{"pmid":"39580461","id":"PMC_39580461","title":"ARMH3 is an ARL5 effector that promotes PI4KB-catalyzed PI4P synthesis at the trans-Golgi network.","date":"2024","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/39580461","citation_count":7,"is_preprint":false},{"pmid":"36921569","id":"PMC_36921569","title":"STeerING PI4P for innate immune activation.","date":"2023","source":"Immunity","url":"https://pubmed.ncbi.nlm.nih.gov/36921569","citation_count":6,"is_preprint":false},{"pmid":"38515862","id":"PMC_38515862","title":"DGARM/C10orf76/ARMH3 for Ceramide Transfer Zone at the Endoplasmic Reticulum-Distal Golgi Contacts.","date":"2024","source":"Contact (Thousand Oaks (Ventura County, Calif.))","url":"https://pubmed.ncbi.nlm.nih.gov/38515862","citation_count":5,"is_preprint":false},{"pmid":"31919962","id":"PMC_31919962","title":"Another hijack! Some enteroviruses co-opt the c10orf76/PI4KB complex for their own good.","date":"2020","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/31919962","citation_count":5,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6450,"output_tokens":2458,"usd":0.02811,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9551,"output_tokens":2786,"usd":0.058702,"stage2_stop_reason":"end_turn"},"total_usd":0.086812,"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\": 2024,\n      \"finding\": \"ARMH3 (C10orf76) binds to active (GTP-bound) but not inactive ARL5, and is recruited to the trans-Golgi network (TGN) in a SYS1-ARFRP1-ARL5-dependent manner, functioning as an ARL5 effector.\",\n      \"method\": \"Proximity biotinylation (BioID) and protein interaction assays; recruitment dependency established by genetic manipulation of SYS1-ARFRP1-ARL5 pathway\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal protein interaction assays with genetic epistasis demonstrating GTP-dependence and pathway placement, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"39580461\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ARMH3, recruited to the TGN via the SYS1-ARFRP1-ARL5 axis, activates PI4KB (phosphatidylinositol 4-kinase IIIβ) to generate the main pool of PI4P at the TGN, which in turn contributes to recruitment of the oncoprotein GOLPH3 and glycan modifications at the TGN.\",\n      \"method\": \"Loss-of-function (KD/KO) with PI4P level measurements at TGN, GOLPH3 localization assay, glycan modification readout\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO/KD with defined cellular phenotypes (PI4P levels, GOLPH3 recruitment, glycan modifications) and pathway placement, single lab but multiple orthogonal readouts\",\n      \"pmids\": [\"39580461\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ARMH3 (DGARM/C10orf76) is not required for retrograde transport of various cargo proteins from endosomes to the TGN, distinguishing its function from that of GARP.\",\n      \"method\": \"Loss-of-function (KO) with retrograde cargo trafficking assay — negative result\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean KO with defined trafficking readout, single lab, single method; negative finding\",\n      \"pmids\": [\"39580461\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Upon cGAMP stimulation, ARMH3 interacts with STING at the Golgi and recruits PI4KB to synthesize PI4P, which directs STING Golgi-to-endosome trafficking via the PI4P-binding proteins AP-1 and GGA2.\",\n      \"method\": \"Genome-wide CRISPR-Cas9 screen to identify ARMH3; co-immunoprecipitation to confirm ARMH3-STING interaction; RNAi knockdown of PI4P-binding proteins; PI4P level measurements; STING trafficking assays\",\n      \"journal\": \"Immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genome-wide screen + Co-IP + functional RNAi knockdowns + in vivo mouse model (Armh3fl/fl;LyzCre mice), multiple orthogonal methods\",\n      \"pmids\": [\"36921576\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Disruption of the ARMH3-PI4KB-PI4P axis impairs STING activation, while aberrantly elevated cellular PI4P leads to cGAS-independent STING activation, and Armh3fl/fl;LyzCre/Cre mice are susceptible to DNA virus challenge in vivo.\",\n      \"method\": \"RNAi knockdown of PI4P-binding proteins; pharmacological manipulation of cellular PI4P levels; conditional knockout mouse model challenged with DNA virus\",\n      \"journal\": \"Immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal approaches including in vivo mouse genetics and pharmacological manipulation, replicated across methods within same study\",\n      \"pmids\": [\"36921576\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"C10orf76 (ARMH3) directly binds PI4KB via the kinase linker region of PI4KB, forming a heterodimeric complex whose assembly is modulated by PKA-dependent phosphorylation of PI4KB.\",\n      \"method\": \"Hydrogen-deuterium exchange mass spectrometry (HDX-MS); complex-disrupting mutagenesis; biochemical binding assays\",\n      \"journal\": \"EMBO Reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — HDX-MS structural characterization with mutagenesis validating binding interface, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"31829496\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"PI4KB is required for membrane recruitment of C10orf76 (ARMH3) to the Golgi, and an intact C10orf76-PI4KB complex is required for Golgi PI4P levels and replication of c10orf76-dependent enteroviruses (e.g., coxsackievirus A10).\",\n      \"method\": \"Complex-disrupting mutations; PI4P level measurements at Golgi; viral replication assays; subcellular localization by fluorescence microscopy\",\n      \"journal\": \"EMBO Reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis combined with PI4P measurements, localization, and functional viral replication readout, multiple orthogonal methods in one study\",\n      \"pmids\": [\"31829496\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"C10orf76 (ARMH3) contributes to proper Arf1 activation at the Golgi, providing a putative mechanism for the C10orf76-dependent increase in PI4P levels.\",\n      \"method\": \"Knockdown with Arf1 activation assay\",\n      \"journal\": \"EMBO Reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single knockdown assay, single lab, single method, described as 'putative mechanism'\",\n      \"pmids\": [\"31829496\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"C10orf76 (ARMH3) interacts with GBF1 (a Golgi-localized ARF guanine nucleotide exchange factor) and rapidly cycles on and off GBF1-positive Golgi structures; its depletion causes Golgi fragmentation, alters GBF1 recruitment, and impairs secretion.\",\n      \"method\": \"BioID proximity biotinylation from Golgi-enriched fractions; co-immunoprecipitation; live-cell imaging; RNAi knockdown with Golgi morphology and secretion readouts\",\n      \"journal\": \"Molecular & Cellular Proteomics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — BioID + Co-IP + live imaging + functional knockdown phenotypes, multiple orthogonal methods in single study\",\n      \"pmids\": [\"31519766\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"C10orf76 (ARMH3) localizes predominantly at distal Golgi regions and, together with PI4KB, generates a PI4P pool that is preferentially utilized by the ceramide transport protein CERT for ER-to-distal-Golgi ceramide trafficking (as opposed to the PI4KB pool recruited by ACBD3).\",\n      \"method\": \"Genome-wide screening; super-resolution microscopy; knockdown/knockout of PI4KB, ACBD3, and C10orf76 with ceramide trafficking assays\",\n      \"journal\": \"Journal of Cell Biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genome-wide screen + super-resolution localization + functional KO/KD with specific lipid trafficking readout, multiple orthogonal methods in one study\",\n      \"pmids\": [\"37195633\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ARMH3 (C10orf76/DGARM) is an armadillo-repeat protein that localizes to the trans-Golgi network (TGN) as an effector of the active GTPase ARL5 (recruited via the SYS1-ARFRP1-ARL5 axis), where it binds PI4KB through its kinase linker region (modulated by PKA phosphorylation) to generate PI4P at the TGN; this PI4P pool drives multiple downstream processes including STING Golgi-to-endosome trafficking and antiviral signaling (via AP-1/GGA2), CERT-mediated ceramide transport at ER-distal Golgi membrane contact sites, GOLPH3 recruitment, glycan modifications, and enterovirus replication organelle formation, while also contributing to Golgi maintenance and secretion through interactions with GBF1 and regulation of Arf1 activation.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ARMH3 (C10orf76/DGARM) is an armadillo-repeat protein that organizes phosphatidylinositol 4-phosphate (PI4P) production at the trans-Golgi network to drive downstream membrane trafficking, lipid transport, and innate immune signaling [#1, #3]. It is recruited to the TGN as an effector of the active GTPase ARL5, binding GTP-bound but not inactive ARL5 in a SYS1-ARFRP1-ARL5-dependent manner [#0]. At the Golgi, ARMH3 forms a heterodimeric complex with PI4KB by binding the PI4KB kinase linker region, an interaction modulated by PKA-dependent phosphorylation of PI4KB; this complex is required both for ARMH3 membrane recruitment and for Golgi PI4P levels [#5, #6]. Through this PI4KB-dependent PI4P pool, ARMH3 promotes recruitment of the oncoprotein GOLPH3 and TGN glycan modifications [#1], and supplies a distal-Golgi PI4P pool preferentially used by the ceramide transport protein CERT for ER-to-Golgi ceramide trafficking [#9]. In innate immunity, ARMH3 interacts with STING at the Golgi upon cGAMP stimulation and recruits PI4KB to generate PI4P that directs STING Golgi-to-endosome trafficking via AP-1 and GGA2; disruption of the ARMH3-PI4KB-PI4P axis impairs STING activation, and Armh3-deficient mice are susceptible to DNA virus challenge [#3, #4]. ARMH3 also interacts with the ARF GEF GBF1 and contributes to Arf1 activation, with its depletion causing Golgi fragmentation and impaired secretion [#7, #8], while its function is distinct from GARP-mediated endosome-to-TGN retrograde transport [#2].\",\n  \"teleology\": [\n    {\n      \"year\": 2019,\n      \"claim\": \"Established the core biochemical interaction underlying ARMH3 function: that it directly binds and partners PI4KB, defining the molecular basis for its role in Golgi PI4P generation.\",\n      \"evidence\": \"HDX-MS, complex-disrupting mutagenesis, and biochemical binding assays mapping the PI4KB kinase linker interface and PKA-phosphorylation modulation\",\n      \"pmids\": [\"31829496\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No high-resolution structure of the heterodimer\", \"Functional consequence of PKA-modulated assembly on PI4P output not quantified\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Showed the ARMH3-PI4KB complex is functionally required, linking complex integrity to Golgi PI4P levels, ARMH3 membrane recruitment, and enterovirus replication.\",\n      \"evidence\": \"Complex-disrupting mutations with Golgi PI4P measurements, localization microscopy, and viral replication assays\",\n      \"pmids\": [\"31829496\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which PI4KB recruits ARMH3 to membranes not resolved\", \"Range of enteroviruses dependent on ARMH3 incompletely defined\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Placed ARMH3 in Golgi maintenance machinery by linking it to GBF1 and Arf1 activation, providing a candidate mechanism for its effect on PI4P and secretion.\",\n      \"evidence\": \"BioID, Co-IP, live-cell imaging, and RNAi knockdown with Golgi morphology, secretion, and Arf1 activation readouts\",\n      \"pmids\": [\"31519766\", \"31829496\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Arf1 activation effect supported by a single knockdown assay described as putative\", \"Direct vs indirect nature of the GBF1-ARMH3 interaction not dissected\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Connected the ARMH3-PI4KB-PI4P axis to innate immunity, showing ARMH3 controls STING Golgi-to-endosome trafficking and antiviral defense in vivo.\",\n      \"evidence\": \"Genome-wide CRISPR screen, ARMH3-STING Co-IP, RNAi of PI4P-binding adaptors, PI4P measurements, STING trafficking assays, and Armh3fl/fl;LyzCre mice challenged with DNA virus\",\n      \"pmids\": [\"36921576\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether STING binding is direct or PI4P-mediated not fully separated\", \"Spatial coupling of ARMH3-STING engagement to ARL5 recruitment unaddressed\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstrated that ARMH3 generates a spatially distinct distal-Golgi PI4P pool dedicated to CERT-mediated ceramide transport, distinguishing it from the ACBD3-recruited PI4KB pool.\",\n      \"evidence\": \"Genome-wide screening, super-resolution microscopy, and KO/KD of PI4KB, ACBD3, and C10orf76 with ceramide trafficking assays\",\n      \"pmids\": [\"37195633\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis for spatial segregation of PI4P pools unresolved\", \"How CERT preferentially reads the ARMH3-dependent pool not defined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined the upstream recruitment logic, establishing ARMH3 as a GTP-dependent ARL5 effector whose TGN localization drives the dominant TGN PI4P pool and downstream GOLPH3/glycosylation, while excluding a GARP-like retrograde role.\",\n      \"evidence\": \"BioID, GTP-dependent interaction and genetic epistasis through SYS1-ARFRP1-ARL5, plus KO with PI4P, GOLPH3, glycan, and retrograde cargo readouts\",\n      \"pmids\": [\"39580461\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How ARL5-dependent recruitment integrates with PI4KB-dependent recruitment not reconciled\", \"Direct effect on glycan-modifying enzymes vs indirect PI4P effect unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ARMH3 spatially and temporally coordinates its distinct PI4P-dependent outputs (STING trafficking, CERT ceramide transport, GOLPH3 recruitment, glycosylation, enterovirus replication) from a single PI4KB-binding activity remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No structural model integrating ARL5, GBF1, and PI4KB engagement\", \"Mechanism partitioning PI4P pools between competing effectors unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [1, 3, 5, 6]},\n      {\"term_id\": \"GO:0060089\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [0, 6, 8, 9]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [3, 9]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [3, 4]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [1, 9]}\n    ],\n    \"complexes\": [\"C10orf76-PI4KB heterodimer\"],\n    \"partners\": [\"PI4KB\", \"ARL5\", \"STING1\", \"GBF1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}