{"gene":"GOLGA4","run_date":"2026-04-28T18:06:53","timeline":{"discoveries":[{"year":1995,"finding":"GOLGA4 (golgin-245/p230) was identified as a 245 kDa Golgi complex autoantigen that is highly enriched in coiled-coil domains and contains a granin family signature decapeptide (ESLALEELEL), identified using autoimmune serum from a Sjögren's syndrome patient to isolate cDNA from a HeLa library.","method":"cDNA library screening with autoimmune serum, recombinant protein expression, immunoprecipitation, Western blot","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — original molecular characterization with multiple orthogonal methods; replicated by independent group (PMID:8626529)","pmids":["8537393"],"is_preprint":false},{"year":1996,"finding":"GOLGA4 (p230) was molecularly cloned and confirmed as a 261 kDa peripheral membrane protein localized to the cytosolic face of the trans-Golgi, containing extensive heptad-repeat coiled-coil domains and a granin motif; its gene was mapped to chromosome 6p12-22. Two alternatively spliced mRNAs differing at the C-terminus were identified.","method":"cDNA cloning, sequence analysis, chromosomal mapping, Northern blot","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — full molecular cloning with sequence and chromosomal localization, confirmed by independent group","pmids":["8626529"],"is_preprint":false},{"year":1996,"finding":"GOLGA4 (p230) localizes to the trans-Golgi network (TGN) and is recruited to cytoplasmic surfaces of TGN-derived budding vesicles with a thin (~10 nm) non-clathrin coat; this recruitment is stimulated by GTPγS or AlF4- (G protein activators), indicating G protein-regulated cycling between cytosol and TGN membranes. p230-labeled vesicles are distinct from clathrin-coated vesicles and from p200-labeled vesicles, suggesting distinct TGN vesicle populations.","method":"Immunogold labeling of cryosections, streptolysin-O permeabilization, G protein activator treatment, dual immunogold labeling","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 1-2 — direct ultrastructural localization with functional perturbation (G protein activators), multiple orthogonal methods","pmids":["9013329"],"is_preprint":false},{"year":1999,"finding":"The C-terminal 98 amino acid domain of GOLGA4 (p230) is necessary and sufficient for targeting to the Golgi apparatus. Within this domain, a minimum stretch of 42 amino acids is essential for Golgi targeting. Overexpression of this domain displaces endogenous p230 from Golgi membranes, suggesting competition for the same membrane target. Golgi binding of this domain is brefeldin A-sensitive and G protein-regulated.","method":"Transfection of COS cells with deletion mutants and GFP fusions, alanine scanning mutagenesis, brefeldin A treatment, immunofluorescence","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 1 — mutagenesis with multiple deletion constructs and functional readout (Golgi targeting/displacement)","pmids":["10318758"],"is_preprint":false},{"year":2004,"finding":"The N-terminal domain of GOLGA4 (p230/golgin-245) directly interacts with the C-terminal domain of MACF1 (a microtubule-actin crosslinking protein), as shown by yeast two-hybrid, co-immunoprecipitation, and in vitro binding assay. Expression of the interacting domains of p230 or MACF1 disrupts transport of GPI-anchored proteins (YFP-SP-GPI) from the TGN to the cell periphery, while transmembrane protein (VSVG3-GL-YFP) trafficking is unaffected, indicating that p230–MACF1 interaction specifically mediates GPI-anchored protein transport along cytoskeletal tracts.","method":"Yeast two-hybrid, co-immunoprecipitation, in vitro binding assay, double immunofluorescence, dominant-negative overexpression with live-cell transport assay","journal":"Experimental cell research","confidence":"High","confidence_rationale":"Tier 2 — reciprocal Co-IP, in vitro binding, functional transport assay with defined cargo specificity; multiple orthogonal methods in single study","pmids":["15265687"],"is_preprint":false},{"year":2008,"finding":"GOLGA4 (p230/golgin-245) physically associates with CD99 in the TGN and is required for surface expression of HLA class I molecules. Overexpression of the GOLGA4 GRIP domain leads to down-modulation of HLA class I at both the cell surface and intracellularly, placing GOLGA4 in the pathway of HLA class I trafficking from TGN to plasma membrane.","method":"Co-immunoprecipitation, overexpression of GRIP domain, immunofluorescence, flow cytometry of HLA class I surface levels","journal":"Blood","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP and functional overexpression phenotype, single study","pmids":["18849489"],"is_preprint":false},{"year":2014,"finding":"GOLGA4 (p230/golgin-245) and its binding partner MACF1 are required for autophagosome formation under amino acid starvation: knockdown of p230 or MACF1 reduces autophagic flux and LC3-positive puncta, and impairs mAtg9 recruitment from the TGN to peripheral phagophores. p230 itself is detected in autophagosomes/autolysosomes during autophagosome biogenesis.","method":"siRNA knockdown, LC3 puncta assay, autophagic flux measurement, immunofluorescence of mAtg9 trafficking, dominant-negative overexpression","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 — KD with defined cellular phenotype and pathway placement (mAtg9 trafficking), single lab","pmids":["25436429"],"is_preprint":false},{"year":2005,"finding":"Active Arl1 GTPase (Arl1-GTP) directly interacts with the GRIP domain of GOLGA4 (golgin-245) to mediate its recruitment to the TGN. GST-Arl1(GTP) recovers endogenous golgin-245 from HeLa cell cytosol, and GST-GRIP domain of golgin-245 retains endogenous active Arl1.","method":"GST pull-down assay with recombinant proteins and HeLa cell lysates","journal":"Methods in enzymology","confidence":"Medium","confidence_rationale":"Tier 3 — biochemical pull-down only, single method, but consistent with broader Arl1-GRIP domain literature","pmids":["16413289"],"is_preprint":false},{"year":2000,"finding":"A novel N-terminal splice variant of GOLGA4 (p230) was identified from a human hepatoma cDNA library; the alternative splicing occurs within the first proline-rich domain and is more frequent than the previously reported form. The splice variant localizes to the TGN similarly to canonical p230, suggesting both isoforms function at the TGN.","method":"cDNA library screening, RT-PCR, immunofluorescence, immunoblotting with GST fusion protein","journal":"European journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 2-3 — molecular identification with localization confirmed by multiple methods; single lab","pmids":["11139141"],"is_preprint":false},{"year":2019,"finding":"A GOLGA4-RAF1 fusion gene was identified in a metastatic melanoma; expression of the fusion was associated with constitutive ERK activation and elevated expression of RAS/RAF downstream effector ETV5, and the tumor showed profound response to MEK inhibitor therapy, indicating the GOLGA4-RAF1 fusion acts as an oncogenic driver through MAPK pathway activation.","method":"Molecular characterization of tumor (RNA sequencing, fusion gene identification), ERK/ETV5 expression analysis, clinical MEK inhibitor response","journal":"The Journal of clinical investigation","confidence":"Medium","confidence_rationale":"Tier 2-3 — molecular and functional characterization in a clinical case with biomarker readout; single case but multiple methods","pmids":["30835257"],"is_preprint":false},{"year":2021,"finding":"A novel GOLGA4-JAK2 fusion gene was identified in B-cell ALL; expression of GOLGA4-JAK2 in murine pro-B cells promoted cytokine-independent growth and constitutive JAK/STAT signaling, and cells were sensitive to JAK inhibitors, implicating GOLGA4-JAK2 as an oncogenic driver via aberrant JAK2 activation.","method":"mRNA sequencing, retroviral expression in murine pro-B cells, cytokine-independent growth assay, JAK/STAT pathway analysis, JAK inhibitor sensitivity","journal":"British journal of haematology","confidence":"Medium","confidence_rationale":"Tier 2 — functional reconstitution in cell line with defined signaling readout; single lab","pmids":["34697799"],"is_preprint":false},{"year":2020,"finding":"GOLGA4 is a Golgi matrix protein highly expressed in mouse testes, but CRISPR/Cas9 global knockout of Golga4 in mice results in normal spermatogenesis, normal sperm morphology, and male fertility, demonstrating that GOLGA4 is dispensable for acrosome biogenesis and spermatogenesis in mice.","method":"CRISPR/Cas9 knockout mouse generation, testicular histology, fertility testing","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 — clean in vivo KO with defined phenotypic readout; single lab","pmids":["32736686"],"is_preprint":false},{"year":2025,"finding":"Super-resolution microscopy and biochemical analysis revealed that GOLGA4, along with other golgins, localizes precisely to the rim of the Golgi apparatus (not between cisternae) and forms anti-parallel dimers that self-assemble into multi-micron-long filamentous bands in vitro, suggesting golgins physically scaffold the Golgi stack structure.","method":"3D super-resolution microscopy (10-20 nm resolution), biochemical characterization of isolated golgin proteins, in vitro self-assembly assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1-2 — cryo/super-resolution structure plus biochemical self-assembly; preprint, not yet peer-reviewed","pmids":[],"is_preprint":true}],"current_model":"GOLGA4 (p230/golgin-245) is a peripheral membrane protein that cycles between the cytosol and the cytoplasmic face of the trans-Golgi network (TGN) in a G protein- and Arl1 GTPase-regulated manner, where its C-terminal GRIP domain anchors it to TGN membranes and its N-terminal domain interacts with MACF1 to facilitate transport of GPI-anchored cargo along cytoskeletal tracks to the cell periphery; it also participates in autophagosome formation by mediating mAtg9 trafficking from the TGN, regulates HLA class I surface expression in complex with CD99, and forms part of a filamentous golgin scaffold at the Golgi rim."},"narrative":{"teleology":[{"year":1995,"claim":"Establishing the molecular identity of GOLGA4 as a coiled-coil Golgi autoantigen resolved the nature of a previously uncharacterized 245 kDa protein recognized by autoimmune sera, opening the gene to functional dissection.","evidence":"cDNA library screening with Sjögren's syndrome autoimmune serum, recombinant protein expression, and immunoprecipitation in HeLa cells","pmids":["8537393"],"confidence":"High","gaps":["Function unknown at this stage","No information on membrane attachment mechanism","Relationship to other golgins undefined"]},{"year":1996,"claim":"Ultrastructural localization of GOLGA4 to the cytosolic face of TGN-derived non-clathrin-coated vesicles, whose recruitment was stimulated by GTPγS/AlF4⁻, established that GOLGA4 cycles between cytosol and TGN membranes under G protein control and marks a distinct TGN vesicle population.","evidence":"Immunogold cryosectioning, streptolysin-O permeabilization with G protein activators, dual immunogold labeling in NRK and HeLa cells","pmids":["9013329","8626529"],"confidence":"High","gaps":["Identity of the G protein mediating recruitment unknown","Cargo carried by p230-positive vesicles undefined","Mechanism of membrane binding unresolved"]},{"year":1999,"claim":"Mapping the minimal C-terminal GRIP domain (42 amino acids) as necessary and sufficient for Golgi targeting revealed the structural basis of GOLGA4 membrane association and that it competes with endogenous protein for a saturable membrane receptor.","evidence":"Transfection of GFP-tagged deletion mutants in COS cells, alanine scanning mutagenesis, brefeldin A treatment","pmids":["10318758"],"confidence":"High","gaps":["Identity of the GRIP domain receptor on TGN membranes not established","No structural information on GRIP-membrane interaction"]},{"year":2004,"claim":"Discovery that the N-terminal domain of GOLGA4 directly binds MACF1 and that this interaction is specifically required for GPI-anchored protein transport from TGN to cell periphery—but dispensable for transmembrane cargo—established GOLGA4 as a cargo-selective adaptor linking TGN sorting to cytoskeletal transport.","evidence":"Yeast two-hybrid, reciprocal co-immunoprecipitation, in vitro binding, live-cell transport assay with dominant-negative constructs","pmids":["15265687"],"confidence":"High","gaps":["How GOLGA4 recognizes GPI-anchored cargo specifically is unknown","Whether other golgins compensate in vivo unclear","No in vivo validation in animal models"]},{"year":2005,"claim":"Demonstrating that Arl1-GTP directly binds the GRIP domain of GOLGA4 identified the specific small GTPase mediating TGN recruitment, resolving the earlier observation of G protein-dependent membrane association.","evidence":"GST pull-down with recombinant Arl1 and HeLa cell lysates","pmids":["16413289"],"confidence":"Medium","gaps":["Only pull-down evidence; no mutagenesis of Arl1-binding interface in GOLGA4","Contribution of Arl1 versus other factors to in vivo recruitment not quantified"]},{"year":2008,"claim":"Finding that GOLGA4 associates with CD99 and is required for HLA class I surface expression expanded its functional repertoire beyond GPI-anchored cargo to immune-relevant transmembrane protein trafficking from the TGN.","evidence":"Co-immunoprecipitation, GRIP domain overexpression, flow cytometry of HLA class I","pmids":["18849489"],"confidence":"Medium","gaps":["Whether GOLGA4 directly binds HLA class I or acts indirectly via CD99 unclear","No loss-of-function confirmation (siRNA/KO)","Physiological relevance in immune cells not tested"]},{"year":2014,"claim":"Showing that GOLGA4 and MACF1 are required for mAtg9 trafficking from the TGN to phagophores during starvation revealed an unexpected role for TGN-based golgin-cytoskeletal coupling in autophagosome biogenesis.","evidence":"siRNA knockdown, LC3 puncta and autophagic flux assays, immunofluorescence of mAtg9 trafficking, dominant-negative expression","pmids":["25436429"],"confidence":"Medium","gaps":["Mechanism by which GOLGA4 selects mAtg9-containing vesicles unknown","Single lab finding; independent replication needed","Whether GOLGA4 is degraded during autophagy or recycled not determined"]},{"year":2020,"claim":"Global knockout of Golga4 in mice showing normal spermatogenesis and fertility despite high testicular expression established functional redundancy among golgins and indicated that GOLGA4 is dispensable for at least some in vivo trafficking processes.","evidence":"CRISPR/Cas9 knockout mouse, testicular histology, fertility assays","pmids":["32736686"],"confidence":"Medium","gaps":["Phenotypic analysis limited to spermatogenesis; other tissues not systematically examined","Compensatory upregulation of other golgins not assessed","Autophagy and immune phenotypes in KO mice not tested"]},{"year":2021,"claim":"Identification of oncogenic GOLGA4-RAF1 and GOLGA4-JAK2 fusion genes in melanoma and B-ALL, respectively, demonstrated that the GOLGA4 locus can serve as a fusion partner driving constitutive kinase signaling, with therapeutic implications for targeted kinase inhibitor therapy.","evidence":"RNA sequencing and fusion gene identification in patient tumors; retroviral reconstitution in murine pro-B cells with signaling readout; clinical MEK/JAK inhibitor responses","pmids":["30835257","34697799"],"confidence":"Medium","gaps":["Whether GOLGA4 coiled-coil domain contributes to oligomerization-dependent kinase activation not tested","Frequency of GOLGA4 fusions in these malignancies unknown","Normal GOLGA4 function not disrupted in these studies"]},{"year":null,"claim":"How GOLGA4 selects specific cargo (GPI-anchored proteins, mAtg9) at the TGN, the structural basis of its filamentous scaffold assembly, and its non-redundant physiological roles beyond spermatogenesis remain unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No cargo recognition mechanism defined","No high-resolution structure of full-length GOLGA4 or GRIP-Arl1 complex","Systematic phenotyping of Golga4 KO mice across tissues not performed"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[0,1,12]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[4,6]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[0,1,2,3,7,8,12]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[2,4,5,6]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[6]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[5]}],"complexes":[],"partners":["MACF1","ARL1","CD99"],"other_free_text":[]},"mechanistic_narrative":"GOLGA4 (golgin-245/p230) is a coiled-coil-rich peripheral membrane protein of the trans-Golgi network (TGN) that functions as a scaffold for selective cargo sorting, cytoskeletal-linked vesicular transport, and autophagosome biogenesis. Its C-terminal GRIP domain is necessary and sufficient for TGN targeting and is recruited by active Arl1 GTPase in a brefeldin A-sensitive, G protein-regulated manner, while overexpression of this domain displaces endogenous GOLGA4 from Golgi membranes [PMID:9013329, PMID:10318758, PMID:16413289]. The N-terminal domain directly binds MACF1, and this interaction is specifically required for transport of GPI-anchored proteins from the TGN to the cell periphery along cytoskeletal tracks, as well as for mAtg9 trafficking from the TGN to phagophores during starvation-induced autophagy [PMID:15265687, PMID:25436429]. GOLGA4 also associates with CD99 and participates in HLA class I surface expression, and despite high expression in testes, global knockout in mice reveals dispensability for spermatogenesis and male fertility [PMID:18849489, PMID:32736686]."},"prefetch_data":{"uniprot":{"accession":"Q13439","full_name":"Golgin subfamily A member 4","aliases":["256 kDa golgin","Golgin-245","Protein 72.1","Trans-Golgi p230"],"length_aa":2230,"mass_kda":261.1,"function":"Involved in vesicular trafficking at the Golgi apparatus level. May play a role in delivery of transport vesicles containing GPI-linked proteins from the trans-Golgi network through its interaction with MACF1. Involved in endosome-to-Golgi trafficking (PubMed:29084197)","subcellular_location":"Cytoplasm; Golgi apparatus membrane; Golgi apparatus, trans-Golgi network membrane","url":"https://www.uniprot.org/uniprotkb/Q13439/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/GOLGA4","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/GOLGA4","total_profiled":1310},"omim":[{"mim_id":"616180","title":"GOLGIN A8 FAMILY, MEMBER A; GOLGA8A","url":"https://www.omim.org/entry/616180"},{"mim_id":"607418","title":"GRIP AND COILED-COIL DOMAINS-CONTAINING PROTEIN 1; GCC1","url":"https://www.omim.org/entry/607418"},{"mim_id":"606918","title":"GOLGIN A5; GOLGA5","url":"https://www.omim.org/entry/606918"},{"mim_id":"604505","title":"THYROID HORMONE RECEPTOR INTERACTOR 11; TRIP11","url":"https://www.omim.org/entry/604505"},{"mim_id":"602580","title":"GOLGIN A2; GOLGA2","url":"https://www.omim.org/entry/602580"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Golgi apparatus","reliability":"Supported"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/GOLGA4"},"hgnc":{"alias_symbol":["golgin-245","GOLG","GCP2","p230","golgin-240"],"prev_symbol":[]},"alphafold":{"accession":"Q13439","domains":[],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13439","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q13439-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q13439-F1-predicted_aligned_error_v6.png","plddt_mean":66.62},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=GOLGA4","jax_strain_url":"https://www.jax.org/strain/search?query=GOLGA4"},"sequence":{"accession":"Q13439","fasta_url":"https://rest.uniprot.org/uniprotkb/Q13439.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q13439/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13439"}},"corpus_meta":[{"pmid":"10224280","id":"PMC_10224280","title":"The P190, P210, and P230 forms of the BCR/ABL oncogene induce a similar chronic myeloid leukemia-like syndrome in mice but have different lymphoid leukemogenic activity.","date":"1999","source":"The Journal of experimental medicine","url":"https://pubmed.ncbi.nlm.nih.gov/10224280","citation_count":408,"is_preprint":false},{"pmid":"8423327","id":"PMC_8423327","title":"Identification of a novel granulocyte chemotactic protein (GCP-2) from human tumor cells. In vitro and in vivo comparison with natural forms of GRO, IP-10, and IL-8.","date":"1993","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/8423327","citation_count":183,"is_preprint":false},{"pmid":"12591113","id":"PMC_12591113","title":"Pharmacological modulation of interleukin-17-induced GCP-2-, GRO-alpha- and interleukin-8 release in human bronchial epithelial cells.","date":"2003","source":"European journal of pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/12591113","citation_count":116,"is_preprint":false},{"pmid":"8537393","id":"PMC_8537393","title":"Molecular characterization of Golgin-245, a novel Golgi complex protein containing a granin signature.","date":"1995","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8537393","citation_count":97,"is_preprint":false},{"pmid":"6339521","id":"PMC_6339521","title":"Immunolocalization of a novel, cytoskeleton-associated polypeptide of Mr 230,000 daltons (p230).","date":"1983","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/6339521","citation_count":87,"is_preprint":false},{"pmid":"8626529","id":"PMC_8626529","title":"Molecular characterization of trans-Golgi p230. A human peripheral membrane protein encoded by a gene on chromosome 6p12-22 contains extensive coiled-coil alpha-helical domains and a granin motif.","date":"1996","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8626529","citation_count":82,"is_preprint":false},{"pmid":"9013329","id":"PMC_9013329","title":"p230 is associated with vesicles budding from the trans-Golgi network.","date":"1996","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/9013329","citation_count":75,"is_preprint":false},{"pmid":"6357780","id":"PMC_6357780","title":"The p36 substrate of tyrosine-specific protein kinases co-localizes with non-erythrocyte alpha-spectrin antigen, p230, in surface lamina of cultured fibroblasts.","date":"1983","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/6357780","citation_count":72,"is_preprint":false},{"pmid":"7606740","id":"PMC_7606740","title":"Establishment and molecular characterization of a novel leukemic cell line with Philadelphia chromosome expressing p230 BCR/ABL fusion protein.","date":"1995","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/7606740","citation_count":71,"is_preprint":false},{"pmid":"22886775","id":"PMC_22886775","title":"Mesenchymal stem cells overexpressing GCP-2 improve heart function through enhanced angiogenic properties in a myocardial infarction model.","date":"2012","source":"Cardiovascular research","url":"https://pubmed.ncbi.nlm.nih.gov/22886775","citation_count":68,"is_preprint":false},{"pmid":"10318758","id":"PMC_10318758","title":"The Golgi-targeting sequence of the peripheral membrane protein p230.","date":"1999","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/10318758","citation_count":65,"is_preprint":false},{"pmid":"15265687","id":"PMC_15265687","title":"Interaction between p230 and MACF1 is associated with transport of a glycosyl phosphatidyl inositol-anchored protein from the Golgi to the cell periphery.","date":"2004","source":"Experimental cell research","url":"https://pubmed.ncbi.nlm.nih.gov/15265687","citation_count":64,"is_preprint":false},{"pmid":"17714428","id":"PMC_17714428","title":"Arabidopsis GCP2 and GCP3 are part of a soluble gamma-tubulin complex and have nuclear envelope targeting domains.","date":"2007","source":"The Plant journal : for cell and molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/17714428","citation_count":60,"is_preprint":false},{"pmid":"10688807","id":"PMC_10688807","title":"GCP-2-induced internalization of IL-8 receptors: hierarchical relationships between GCP-2 and other ELR(+)-CXC chemokines and mechanisms regulating CXCR2 internalization and recycling.","date":"2000","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/10688807","citation_count":57,"is_preprint":false},{"pmid":"15988615","id":"PMC_15988615","title":"Lipid peroxides, superoxide dismutase and circulating IL-8 and GCP-2 in patients with severe obstructive sleep apnea: a pilot study.","date":"2005","source":"Sleep & breathing = Schlaf & Atmung","url":"https://pubmed.ncbi.nlm.nih.gov/15988615","citation_count":57,"is_preprint":false},{"pmid":"14632302","id":"PMC_14632302","title":"Genotype frequencies and linkage disequilibrium in the CEPH human diversity panel for variants in folate pathway genes MTHFR, MTHFD, MTRR, RFC1, and GCP2.","date":"2003","source":"Birth defects research. 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haematology","url":"https://pubmed.ncbi.nlm.nih.gov/34697799","citation_count":5,"is_preprint":false},{"pmid":"23886939","id":"PMC_23886939","title":"Functional replacement of fission yeast γ-tubulin small complex proteins Alp4 and Alp6 by human GCP2 and GCP3.","date":"2013","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/23886939","citation_count":5,"is_preprint":false},{"pmid":"23956893","id":"PMC_23956893","title":"Early Complete Molecular Response to First-Line Nilotinib in Two Patients with Chronic Myeloid Leukemia Carrying the p230 Transcript.","date":"2013","source":"Case reports in hematology","url":"https://pubmed.ncbi.nlm.nih.gov/23956893","citation_count":5,"is_preprint":false},{"pmid":"17118762","id":"PMC_17118762","title":"Oral administration of imatinib to P230 BCR/ABL-expressing transgenic mice changes clones with high BCR/ABL complementary DNA expression into those with low expression.","date":"2006","source":"International journal of hematology","url":"https://pubmed.ncbi.nlm.nih.gov/17118762","citation_count":4,"is_preprint":false},{"pmid":"37288817","id":"PMC_37288817","title":"De nove Philadelphia chromosome-positive myelodysplastic syndromes with complex karyotype and p230 BCR::ABL fusion transcript: a case report with a literature review.","date":"2023","source":"Hematology (Amsterdam, Netherlands)","url":"https://pubmed.ncbi.nlm.nih.gov/37288817","citation_count":2,"is_preprint":false},{"pmid":"41258756","id":"PMC_41258756","title":"Senescent Fibroblasts Drive Melanoma Progression Through GCP-2 Induced CREB Phosphorylation Enhancing Glycolysis.","date":"2025","source":"Aging cell","url":"https://pubmed.ncbi.nlm.nih.gov/41258756","citation_count":1,"is_preprint":false},{"pmid":"34893105","id":"PMC_34893105","title":"[Clinical Effect of Tyrosine Kinase Inhibitors in the Treatment of P230 Chronic Myeloid Leukemia].","date":"2021","source":"Zhongguo shi yan xue ye xue za zhi","url":"https://pubmed.ncbi.nlm.nih.gov/34893105","citation_count":1,"is_preprint":false},{"pmid":"9498558","id":"PMC_9498558","title":"Isolation and characterization of a 230 kDa protein (p230) specifically expressed in fetal brains: its involvement in neurite outgrowth from rat cerebral cortex neurons grown on monolayer of astrocytes.","date":"1997","source":"Journal of biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/9498558","citation_count":0,"is_preprint":false},{"pmid":"41148513","id":"PMC_41148513","title":"Philadelphia chromosome-positive de novo myelodysplastic syndrome with the p230 BCR::ABL1 fusion gene: a case report.","date":"2025","source":"International journal of hematology","url":"https://pubmed.ncbi.nlm.nih.gov/41148513","citation_count":0,"is_preprint":false},{"pmid":"42040683","id":"PMC_42040683","title":"Inferior Outcomes of p230-CML with Imatinib: a Report of 2 Cases of p210/p230 Co-Expressed CML Showing Rapid Progression To Leukaemia Cutis along with the Systematic Review.","date":"2025","source":"Indian journal of hematology & blood transfusion : an official journal of Indian Society of Hematology and Blood Transfusion","url":"https://pubmed.ncbi.nlm.nih.gov/42040683","citation_count":0,"is_preprint":false},{"pmid":"31053746","id":"PMC_31053746","title":"Author Correction: The Plasmodium falciparum male gametocyte protein P230p, a paralog of P230, is vital for ookinete formation and mosquito transmission.","date":"2019","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/31053746","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.11.05.622067","title":"Structure of the microtubule anchoring factor NEDD1 bound to the γ-tubulin ring complex","date":"2024-11-05","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.05.622067","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.03.27.645134","title":"The Golgi Rim is a Precise Tetraplex of Golgin Proteins that Can Self-Assemble into Filamentous Bands","date":"2025-03-28","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.27.645134","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.06.11.598534","title":"Comparative analysis of new, mScarlet-based red fluorescent tags in<i>Caenorhabditis elegans</i>","date":"2024-06-13","source":"bioRxiv","url":"https://doi.org/10.1101/2024.06.11.598534","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":26556,"output_tokens":3297,"usd":0.064561},"stage2":{"model":"claude-opus-4-6","input_tokens":6665,"output_tokens":2503,"usd":0.14385},"total_usd":0.208411,"stage1_batch_id":"msgbatch_01DzrsgVgYngY1hvM3DU1yF2","stage2_batch_id":"msgbatch_01KA9b7iRzKFdhoBUT7vCvSe","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1995,\n      \"finding\": \"GOLGA4 (golgin-245/p230) was identified as a 245 kDa Golgi complex autoantigen that is highly enriched in coiled-coil domains and contains a granin family signature decapeptide (ESLALEELEL), identified using autoimmune serum from a Sjögren's syndrome patient to isolate cDNA from a HeLa library.\",\n      \"method\": \"cDNA library screening with autoimmune serum, recombinant protein expression, immunoprecipitation, Western blot\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — original molecular characterization with multiple orthogonal methods; replicated by independent group (PMID:8626529)\",\n      \"pmids\": [\"8537393\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"GOLGA4 (p230) was molecularly cloned and confirmed as a 261 kDa peripheral membrane protein localized to the cytosolic face of the trans-Golgi, containing extensive heptad-repeat coiled-coil domains and a granin motif; its gene was mapped to chromosome 6p12-22. Two alternatively spliced mRNAs differing at the C-terminus were identified.\",\n      \"method\": \"cDNA cloning, sequence analysis, chromosomal mapping, Northern blot\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — full molecular cloning with sequence and chromosomal localization, confirmed by independent group\",\n      \"pmids\": [\"8626529\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"GOLGA4 (p230) localizes to the trans-Golgi network (TGN) and is recruited to cytoplasmic surfaces of TGN-derived budding vesicles with a thin (~10 nm) non-clathrin coat; this recruitment is stimulated by GTPγS or AlF4- (G protein activators), indicating G protein-regulated cycling between cytosol and TGN membranes. p230-labeled vesicles are distinct from clathrin-coated vesicles and from p200-labeled vesicles, suggesting distinct TGN vesicle populations.\",\n      \"method\": \"Immunogold labeling of cryosections, streptolysin-O permeabilization, G protein activator treatment, dual immunogold labeling\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — direct ultrastructural localization with functional perturbation (G protein activators), multiple orthogonal methods\",\n      \"pmids\": [\"9013329\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"The C-terminal 98 amino acid domain of GOLGA4 (p230) is necessary and sufficient for targeting to the Golgi apparatus. Within this domain, a minimum stretch of 42 amino acids is essential for Golgi targeting. Overexpression of this domain displaces endogenous p230 from Golgi membranes, suggesting competition for the same membrane target. Golgi binding of this domain is brefeldin A-sensitive and G protein-regulated.\",\n      \"method\": \"Transfection of COS cells with deletion mutants and GFP fusions, alanine scanning mutagenesis, brefeldin A treatment, immunofluorescence\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — mutagenesis with multiple deletion constructs and functional readout (Golgi targeting/displacement)\",\n      \"pmids\": [\"10318758\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The N-terminal domain of GOLGA4 (p230/golgin-245) directly interacts with the C-terminal domain of MACF1 (a microtubule-actin crosslinking protein), as shown by yeast two-hybrid, co-immunoprecipitation, and in vitro binding assay. Expression of the interacting domains of p230 or MACF1 disrupts transport of GPI-anchored proteins (YFP-SP-GPI) from the TGN to the cell periphery, while transmembrane protein (VSVG3-GL-YFP) trafficking is unaffected, indicating that p230–MACF1 interaction specifically mediates GPI-anchored protein transport along cytoskeletal tracts.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, in vitro binding assay, double immunofluorescence, dominant-negative overexpression with live-cell transport assay\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP, in vitro binding, functional transport assay with defined cargo specificity; multiple orthogonal methods in single study\",\n      \"pmids\": [\"15265687\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"GOLGA4 (p230/golgin-245) physically associates with CD99 in the TGN and is required for surface expression of HLA class I molecules. Overexpression of the GOLGA4 GRIP domain leads to down-modulation of HLA class I at both the cell surface and intracellularly, placing GOLGA4 in the pathway of HLA class I trafficking from TGN to plasma membrane.\",\n      \"method\": \"Co-immunoprecipitation, overexpression of GRIP domain, immunofluorescence, flow cytometry of HLA class I surface levels\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP and functional overexpression phenotype, single study\",\n      \"pmids\": [\"18849489\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"GOLGA4 (p230/golgin-245) and its binding partner MACF1 are required for autophagosome formation under amino acid starvation: knockdown of p230 or MACF1 reduces autophagic flux and LC3-positive puncta, and impairs mAtg9 recruitment from the TGN to peripheral phagophores. p230 itself is detected in autophagosomes/autolysosomes during autophagosome biogenesis.\",\n      \"method\": \"siRNA knockdown, LC3 puncta assay, autophagic flux measurement, immunofluorescence of mAtg9 trafficking, dominant-negative overexpression\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — KD with defined cellular phenotype and pathway placement (mAtg9 trafficking), single lab\",\n      \"pmids\": [\"25436429\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Active Arl1 GTPase (Arl1-GTP) directly interacts with the GRIP domain of GOLGA4 (golgin-245) to mediate its recruitment to the TGN. GST-Arl1(GTP) recovers endogenous golgin-245 from HeLa cell cytosol, and GST-GRIP domain of golgin-245 retains endogenous active Arl1.\",\n      \"method\": \"GST pull-down assay with recombinant proteins and HeLa cell lysates\",\n      \"journal\": \"Methods in enzymology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — biochemical pull-down only, single method, but consistent with broader Arl1-GRIP domain literature\",\n      \"pmids\": [\"16413289\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"A novel N-terminal splice variant of GOLGA4 (p230) was identified from a human hepatoma cDNA library; the alternative splicing occurs within the first proline-rich domain and is more frequent than the previously reported form. The splice variant localizes to the TGN similarly to canonical p230, suggesting both isoforms function at the TGN.\",\n      \"method\": \"cDNA library screening, RT-PCR, immunofluorescence, immunoblotting with GST fusion protein\",\n      \"journal\": \"European journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — molecular identification with localization confirmed by multiple methods; single lab\",\n      \"pmids\": [\"11139141\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"A GOLGA4-RAF1 fusion gene was identified in a metastatic melanoma; expression of the fusion was associated with constitutive ERK activation and elevated expression of RAS/RAF downstream effector ETV5, and the tumor showed profound response to MEK inhibitor therapy, indicating the GOLGA4-RAF1 fusion acts as an oncogenic driver through MAPK pathway activation.\",\n      \"method\": \"Molecular characterization of tumor (RNA sequencing, fusion gene identification), ERK/ETV5 expression analysis, clinical MEK inhibitor response\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — molecular and functional characterization in a clinical case with biomarker readout; single case but multiple methods\",\n      \"pmids\": [\"30835257\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"A novel GOLGA4-JAK2 fusion gene was identified in B-cell ALL; expression of GOLGA4-JAK2 in murine pro-B cells promoted cytokine-independent growth and constitutive JAK/STAT signaling, and cells were sensitive to JAK inhibitors, implicating GOLGA4-JAK2 as an oncogenic driver via aberrant JAK2 activation.\",\n      \"method\": \"mRNA sequencing, retroviral expression in murine pro-B cells, cytokine-independent growth assay, JAK/STAT pathway analysis, JAK inhibitor sensitivity\",\n      \"journal\": \"British journal of haematology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — functional reconstitution in cell line with defined signaling readout; single lab\",\n      \"pmids\": [\"34697799\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"GOLGA4 is a Golgi matrix protein highly expressed in mouse testes, but CRISPR/Cas9 global knockout of Golga4 in mice results in normal spermatogenesis, normal sperm morphology, and male fertility, demonstrating that GOLGA4 is dispensable for acrosome biogenesis and spermatogenesis in mice.\",\n      \"method\": \"CRISPR/Cas9 knockout mouse generation, testicular histology, fertility testing\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean in vivo KO with defined phenotypic readout; single lab\",\n      \"pmids\": [\"32736686\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Super-resolution microscopy and biochemical analysis revealed that GOLGA4, along with other golgins, localizes precisely to the rim of the Golgi apparatus (not between cisternae) and forms anti-parallel dimers that self-assemble into multi-micron-long filamentous bands in vitro, suggesting golgins physically scaffold the Golgi stack structure.\",\n      \"method\": \"3D super-resolution microscopy (10-20 nm resolution), biochemical characterization of isolated golgin proteins, in vitro self-assembly assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 — cryo/super-resolution structure plus biochemical self-assembly; preprint, not yet peer-reviewed\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"GOLGA4 (p230/golgin-245) is a peripheral membrane protein that cycles between the cytosol and the cytoplasmic face of the trans-Golgi network (TGN) in a G protein- and Arl1 GTPase-regulated manner, where its C-terminal GRIP domain anchors it to TGN membranes and its N-terminal domain interacts with MACF1 to facilitate transport of GPI-anchored cargo along cytoskeletal tracks to the cell periphery; it also participates in autophagosome formation by mediating mAtg9 trafficking from the TGN, regulates HLA class I surface expression in complex with CD99, and forms part of a filamentous golgin scaffold at the Golgi rim.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"GOLGA4 (golgin-245/p230) is a coiled-coil-rich peripheral membrane protein of the trans-Golgi network (TGN) that functions as a scaffold for selective cargo sorting, cytoskeletal-linked vesicular transport, and autophagosome biogenesis. Its C-terminal GRIP domain is necessary and sufficient for TGN targeting and is recruited by active Arl1 GTPase in a brefeldin A-sensitive, G protein-regulated manner, while overexpression of this domain displaces endogenous GOLGA4 from Golgi membranes [PMID:9013329, PMID:10318758, PMID:16413289]. The N-terminal domain directly binds MACF1, and this interaction is specifically required for transport of GPI-anchored proteins from the TGN to the cell periphery along cytoskeletal tracks, as well as for mAtg9 trafficking from the TGN to phagophores during starvation-induced autophagy [PMID:15265687, PMID:25436429]. GOLGA4 also associates with CD99 and participates in HLA class I surface expression, and despite high expression in testes, global knockout in mice reveals dispensability for spermatogenesis and male fertility [PMID:18849489, PMID:32736686].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Establishing the molecular identity of GOLGA4 as a coiled-coil Golgi autoantigen resolved the nature of a previously uncharacterized 245 kDa protein recognized by autoimmune sera, opening the gene to functional dissection.\",\n      \"evidence\": \"cDNA library screening with Sjögren's syndrome autoimmune serum, recombinant protein expression, and immunoprecipitation in HeLa cells\",\n      \"pmids\": [\"8537393\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Function unknown at this stage\", \"No information on membrane attachment mechanism\", \"Relationship to other golgins undefined\"]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Ultrastructural localization of GOLGA4 to the cytosolic face of TGN-derived non-clathrin-coated vesicles, whose recruitment was stimulated by GTPγS/AlF4⁻, established that GOLGA4 cycles between cytosol and TGN membranes under G protein control and marks a distinct TGN vesicle population.\",\n      \"evidence\": \"Immunogold cryosectioning, streptolysin-O permeabilization with G protein activators, dual immunogold labeling in NRK and HeLa cells\",\n      \"pmids\": [\"9013329\", \"8626529\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of the G protein mediating recruitment unknown\", \"Cargo carried by p230-positive vesicles undefined\", \"Mechanism of membrane binding unresolved\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Mapping the minimal C-terminal GRIP domain (42 amino acids) as necessary and sufficient for Golgi targeting revealed the structural basis of GOLGA4 membrane association and that it competes with endogenous protein for a saturable membrane receptor.\",\n      \"evidence\": \"Transfection of GFP-tagged deletion mutants in COS cells, alanine scanning mutagenesis, brefeldin A treatment\",\n      \"pmids\": [\"10318758\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of the GRIP domain receptor on TGN membranes not established\", \"No structural information on GRIP-membrane interaction\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Discovery that the N-terminal domain of GOLGA4 directly binds MACF1 and that this interaction is specifically required for GPI-anchored protein transport from TGN to cell periphery—but dispensable for transmembrane cargo—established GOLGA4 as a cargo-selective adaptor linking TGN sorting to cytoskeletal transport.\",\n      \"evidence\": \"Yeast two-hybrid, reciprocal co-immunoprecipitation, in vitro binding, live-cell transport assay with dominant-negative constructs\",\n      \"pmids\": [\"15265687\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How GOLGA4 recognizes GPI-anchored cargo specifically is unknown\", \"Whether other golgins compensate in vivo unclear\", \"No in vivo validation in animal models\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Demonstrating that Arl1-GTP directly binds the GRIP domain of GOLGA4 identified the specific small GTPase mediating TGN recruitment, resolving the earlier observation of G protein-dependent membrane association.\",\n      \"evidence\": \"GST pull-down with recombinant Arl1 and HeLa cell lysates\",\n      \"pmids\": [\"16413289\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Only pull-down evidence; no mutagenesis of Arl1-binding interface in GOLGA4\", \"Contribution of Arl1 versus other factors to in vivo recruitment not quantified\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Finding that GOLGA4 associates with CD99 and is required for HLA class I surface expression expanded its functional repertoire beyond GPI-anchored cargo to immune-relevant transmembrane protein trafficking from the TGN.\",\n      \"evidence\": \"Co-immunoprecipitation, GRIP domain overexpression, flow cytometry of HLA class I\",\n      \"pmids\": [\"18849489\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether GOLGA4 directly binds HLA class I or acts indirectly via CD99 unclear\", \"No loss-of-function confirmation (siRNA/KO)\", \"Physiological relevance in immune cells not tested\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Showing that GOLGA4 and MACF1 are required for mAtg9 trafficking from the TGN to phagophores during starvation revealed an unexpected role for TGN-based golgin-cytoskeletal coupling in autophagosome biogenesis.\",\n      \"evidence\": \"siRNA knockdown, LC3 puncta and autophagic flux assays, immunofluorescence of mAtg9 trafficking, dominant-negative expression\",\n      \"pmids\": [\"25436429\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which GOLGA4 selects mAtg9-containing vesicles unknown\", \"Single lab finding; independent replication needed\", \"Whether GOLGA4 is degraded during autophagy or recycled not determined\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Global knockout of Golga4 in mice showing normal spermatogenesis and fertility despite high testicular expression established functional redundancy among golgins and indicated that GOLGA4 is dispensable for at least some in vivo trafficking processes.\",\n      \"evidence\": \"CRISPR/Cas9 knockout mouse, testicular histology, fertility assays\",\n      \"pmids\": [\"32736686\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Phenotypic analysis limited to spermatogenesis; other tissues not systematically examined\", \"Compensatory upregulation of other golgins not assessed\", \"Autophagy and immune phenotypes in KO mice not tested\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Identification of oncogenic GOLGA4-RAF1 and GOLGA4-JAK2 fusion genes in melanoma and B-ALL, respectively, demonstrated that the GOLGA4 locus can serve as a fusion partner driving constitutive kinase signaling, with therapeutic implications for targeted kinase inhibitor therapy.\",\n      \"evidence\": \"RNA sequencing and fusion gene identification in patient tumors; retroviral reconstitution in murine pro-B cells with signaling readout; clinical MEK/JAK inhibitor responses\",\n      \"pmids\": [\"30835257\", \"34697799\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether GOLGA4 coiled-coil domain contributes to oligomerization-dependent kinase activation not tested\", \"Frequency of GOLGA4 fusions in these malignancies unknown\", \"Normal GOLGA4 function not disrupted in these studies\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How GOLGA4 selects specific cargo (GPI-anchored proteins, mAtg9) at the TGN, the structural basis of its filamentous scaffold assembly, and its non-redundant physiological roles beyond spermatogenesis remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No cargo recognition mechanism defined\", \"No high-resolution structure of full-length GOLGA4 or GRIP-Arl1 complex\", \"Systematic phenotyping of Golga4 KO mice across tissues not performed\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 1, 12]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [4, 6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [0, 1, 2, 3, 7, 8, 12]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [2, 4, 5, 6]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [6]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"MACF1\",\n      \"ARL1\",\n      \"CD99\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}