{"gene":"VAMP4","run_date":"2026-04-28T23:00:23","timeline":{"discoveries":[{"year":2012,"finding":"VAMP4 forms a stable SNARE complex with syntaxin-1 and SNAP-25 that does not interact with complexins or synaptotagmin-1 (proteins essential for synchronous neurotransmission), and this distinct complex selectively maintains Ca2+-dependent asynchronous neurotransmitter release at inhibitory nerve terminals. Up- or downregulation of VAMP4 causes a correlated change in asynchronous release. VAMP4 and synaptobrevin2 traffic independently with minimal overlap.","method":"Biochemical SNARE complex pulldown, up/downregulation of VAMP4 in neurons with electrophysiological readout, optical imaging of individual synapses","journal":"Nature neuroscience","confidence":"High","confidence_rationale":"Tier 1-2 — multiple orthogonal methods (biochemistry, electrophysiology, imaging), replicated across conditions","pmids":["22406549"],"is_preprint":false},{"year":2007,"finding":"VAMP4 cycles from the cell surface to the TGN via clathrin-dependent endocytosis through sorting and then recycling endosomes (not late endosomes). The di-leucine motif of the TGN-targeting signal is important for internalization, while the acidic cluster is crucial for delivery from endosome to TGN.","method":"Live-cell imaging of VAMP4-EGFP, antibody uptake assays, pharmacological and thermal perturbation, site-directed mutagenesis","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods including mutagenesis and pharmacological perturbation in a single study","pmids":["17327277"],"is_preprint":false},{"year":2003,"finding":"VAMP4 binds to AP-1 subunit mu1a (but not mu1b or GGAs) via its dileucine motif (Leu25,26) and Ser20. Phosphorylation of Ser30 in the acidic cluster by casein kinase 2 enhances AP-1 binding via PACS-1. Ablation of both the dileucine motif and Ser30, or dominant-negative PACS-1, causes dramatic mislocalization of VAMP4 in AtT20 cells.","method":"Co-immunoprecipitation, site-directed mutagenesis, dominant-negative PACS-1 expression, fluorescence microscopy","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 1-2 — mutagenesis combined with binding assays and functional mislocalization readout","pmids":["14608369"],"is_preprint":false},{"year":2003,"finding":"The N-terminal 51-residue extension of VAMP4 (containing a di-leucine motif followed by two acidic clusters) is a dominant and autonomous targeting signal sufficient to redirect VAMP5 to the TGN. The di-leucine motif and the second acidic cluster are essential for TGN targeting.","method":"Domain-swap chimeras between VAMP4 and VAMP5, C-terminal EGFP tagging, deletion and site-directed mutagenesis, fluorescence microscopy","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — domain-swap chimeras plus site-directed mutagenesis with clear subcellular localization readout","pmids":["12682051"],"is_preprint":false},{"year":2008,"finding":"VAMP4 is localized in enlargeosome membranes and is a required component of the SNARE machinery (together with syntaxin-6 and SNAP23) mediating regulated exocytosis of enlargeosomes. Anti-VAMP4 antibody microinjection and VAMP4 siRNA both inhibit enlargeosome exocytosis.","method":"Immunolocalization, anti-VAMP4 antibody microinjection, siRNA knockdown, capacitance measurements, VAMP4-GFP live imaging","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 — multiple methods (electrophysiology, antibody inhibition, siRNA, live imaging) converging on same conclusion","pmids":["18713833"],"is_preprint":false},{"year":2015,"finding":"VAMP4 is an essential cargo molecule for activity-dependent bulk endocytosis (ADBE) at synapses, with a cytoplasmic di-leucine motif being critical for this role. VAMP4 is selectively retrieved by ADBE and is enriched in bulk endosomes; inhibiting ADBE specifically perturbs VAMP4-pHluorin retrieval but not other SV cargo reporters.","method":"pH-sensitive pHluorin reporters in neuronal cultures, genetic inhibition of ADBE, purification of bulk endosomes with western blotting, di-leucine motif mutagenesis","journal":"Neuron","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods including functional reporters, biochemical fractionation, and mutagenesis","pmids":["26607000"],"is_preprint":false},{"year":2011,"finding":"In NK cells, VAMP4 colocalizes with lytic granules during cytotoxic interactions and is required for cytotoxic granule exocytosis and NK cell cytotoxic activity. VAMP4 knockdown inhibits lytic granule release but does not affect IFN-γ secretion, distinguishing its function from VAMP7.","method":"Immunofluorescence colocalization, siRNA knockdown, cytotoxicity assays in YTS cells and peripheral NK cells","journal":"European journal of immunology","confidence":"Medium","confidence_rationale":"Tier 2 — siRNA knockdown with specific functional readout (granule exocytosis vs IFN-γ secretion)","pmids":["21805468"],"is_preprint":false},{"year":2013,"finding":"VAMP4 is required to maintain the Golgi ribbon structure. Depletion of VAMP4 by RNAi causes Golgi ribbon fragmentation (shortened stacks remaining in juxtanuclear area) without disrupting anterograde trafficking or microtubule arrays. Depletion of VAMP4 cognate SNARE partners (syntaxin 6, syntaxin 16, Vti1a) similarly disrupts the Golgi ribbon, implicating the VAMP4-containing SNARE complex in retrograde trafficking needed for Golgi integrity.","method":"RNAi knockdown in HeLa cells, electron microscopy, immunofluorescence, anterograde trafficking assays","journal":"Molecular and cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 — RNAi with multiple readouts (EM, IF, trafficking assays) in a single study","pmids":["23677696"],"is_preprint":false},{"year":2021,"finding":"VAMP4 copy number on synaptic vesicles regulates release probability (Pr): VAMP4 has reduced ability to form efficient SNARE complexes with canonical plasma membrane SNAREs, and its high synaptic turnover is coupled to selective sorting to endolysosomes during activity-dependent bulk endocytosis. Disruption of endolysosomal trafficking increases VAMP4 abundance in the SV pool and inhibits SV fusion.","method":"SNARE complex reconstitution assay, fluorescence imaging, endolysosomal trafficking perturbation, pHluorin reporters, mass spectrometry","journal":"Science advances","confidence":"High","confidence_rationale":"Tier 1-2 — in vitro SNARE complex assay combined with live imaging and trafficking perturbation experiments","pmids":["33931449"],"is_preprint":false},{"year":2020,"finding":"VAMP4 is required for Ca2+-dependent spontaneous excitatory neurotransmission in hippocampal neurons. Key residues controlling VAMP4 retrieval and functional clathrin-mediated trafficking are essential for maintaining VAMP4-mediated spontaneous release. High-frequency stimulation augments Ca2+-sensitive spontaneous release for up to 30 min in a VAMP4-dependent manner, linking asynchronous and spontaneous release.","method":"siRNA knockdown and rescue with VAMP4 mutants in hippocampal neurons, electrophysiology (mEPSC/mIPSC recording), high-frequency stimulation protocols","journal":"The Journal of neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 — electrophysiology with mutagenesis in a single study","pmids":["32532887"],"is_preprint":false},{"year":2021,"finding":"VAMP4 is the primary vesicular SNARE mediating dendritic recycling endosome exocytosis. VAMP4 knockdown decreases transferrin receptor (TfR) recycling but paradoxically increases AMPA receptor (AMPAR) recycling and synaptic transmission, occluding LTP, revealing that VAMP4 sorts AMPARs and TfRs into separate endosomal populations.","method":"VAMP4 knockdown in neurons, live imaging of VAMP4-labeled organelles, electrophysiology (LTP, AMPAR-mediated transmission), TfR recycling assays","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 — knockdown with multiple functional readouts (imaging, electrophysiology, receptor recycling)","pmids":["34496238"],"is_preprint":false},{"year":2021,"finding":"VAMP4 on Golgi-derived vesicles forms a trans-SNARE complex with the Q-SNARE complex Stx6/Stx7/Vti1b to mediate fusion with late endosomes, regulating transport of MT1-MMP from Golgi to late endosomes and subsequently to the cell surface in macrophages. Depletion of any SNARE in this complex reduces surface MT1-MMP and gelatin degradation.","method":"Fixed and live imaging, co-immunoprecipitation (trans-SNARE complex), siRNA knockdown, gelatin degradation assay","journal":"Traffic","confidence":"Medium","confidence_rationale":"Tier 2 — Co-IP of trans-SNARE complex combined with functional knockdown assays","pmids":["34476885"],"is_preprint":false}],"current_model":"VAMP4 is a TGN-enriched R-SNARE whose N-terminal di-leucine/acidic-cluster motif directs it to the TGN via AP-1/PACS-1-dependent, clathrin-mediated recycling from the cell surface through sorting and recycling endosomes; at synapses, it forms SNARE complexes that lack synaptotagmin-1 and complexin binding, driving asynchronous and Ca2+-sensitive spontaneous neurotransmission, while its selective sorting to endolysosomes via activity-dependent bulk endocytosis controls its copy number on synaptic vesicles and thereby regulates release probability; in non-neuronal cells it partners with Stx6/Stx7/Vti1b for Golgi-to-late-endosome trafficking and is required for enlargeosome exocytosis, Golgi ribbon maintenance, and NK-cell cytotoxic granule exocytosis."},"narrative":{"teleology":[{"year":2003,"claim":"Identification of the N-terminal di-leucine/acidic-cluster motif as a dominant TGN-targeting signal established the structural basis for VAMP4's steady-state localization, answering how VAMP4 is distinguished from other VAMPs that lack this extension.","evidence":"Domain-swap chimeras between VAMP4 and VAMP5, site-directed mutagenesis with fluorescence microscopy in COS cells; parallel AP-1 binding assays and PACS-1 dominant-negative experiments in AtT20 cells","pmids":["12682051","14608369"],"confidence":"High","gaps":["Structural basis for CK2 phosphorylation-dependent enhancement of AP-1 binding not resolved","In vivo relevance of TGN targeting in neuronal vs. non-neuronal contexts not compared"]},{"year":2007,"claim":"Tracing VAMP4's full itinerary from the plasma membrane through sorting and recycling endosomes back to the TGN resolved the recycling route and assigned distinct roles to the di-leucine motif (internalization) versus the acidic cluster (endosome-to-TGN delivery).","evidence":"Live-cell imaging of VAMP4-EGFP, antibody uptake assays, temperature blocks, and mutagenesis in HeLa cells","pmids":["17327277"],"confidence":"High","gaps":["Coat/adaptor complexes acting at the endosome-to-TGN step not fully identified","Kinetic parameters of recycling not quantified"]},{"year":2008,"claim":"Demonstrating that VAMP4 is a required SNARE for enlargeosome exocytosis (with syntaxin-6 and SNAP23) established VAMP4's first known role in regulated secretion in non-neuronal cells.","evidence":"Anti-VAMP4 antibody microinjection, siRNA knockdown, capacitance measurements, and live imaging in U2OS cells","pmids":["18713833"],"confidence":"High","gaps":["How VAMP4 is recruited to enlargeosomes is unknown","Whether VAMP4 participates in the Ca²⁺ sensor interaction for enlargeosome fusion is unclear"]},{"year":2011,"claim":"Showing that VAMP4 knockdown specifically inhibits cytotoxic granule exocytosis but not IFN-γ secretion in NK cells demonstrated cargo-selective SNARE function in immune effector cells.","evidence":"siRNA knockdown, immunofluorescence, and cytotoxicity assays in YTS and primary NK cells","pmids":["21805468"],"confidence":"Medium","gaps":["SNARE partners for VAMP4 at the NK cell lytic granule not identified","Single knockdown study without rescue experiment"]},{"year":2012,"claim":"Discovery that VAMP4 forms SNARE complexes lacking complexin and synaptotagmin-1 binding and selectively supports asynchronous neurotransmitter release fundamentally established a molecularly distinct fusion machinery for asynchronous versus synchronous transmission.","evidence":"Biochemical SNARE complex pulldown, electrophysiology and optical imaging with VAMP4 up/downregulation in cultured hippocampal neurons","pmids":["22406549"],"confidence":"High","gaps":["Ca²⁺ sensor driving VAMP4-dependent asynchronous release not identified","Whether VAMP4 SNARE complexes operate at excitatory synapses not tested in this study"]},{"year":2013,"claim":"Demonstrating that VAMP4 depletion fragments the Golgi ribbon without disrupting anterograde transport revealed a role in retrograde trafficking required for Golgi structural integrity, mediated by a complex including syntaxin-6, syntaxin-16, and Vti1a.","evidence":"RNAi knockdown in HeLa cells with electron microscopy, immunofluorescence, and anterograde trafficking assays","pmids":["23677696"],"confidence":"Medium","gaps":["Cargo carried by VAMP4-dependent retrograde pathway not identified","Whether Golgi fragmentation reflects direct SNARE function or indirect effect not fully resolved"]},{"year":2015,"claim":"Identifying VAMP4 as a selective cargo of activity-dependent bulk endocytosis (ADBE) via its di-leucine motif resolved how VAMP4 is retrieved from the presynaptic surface by a pathway distinct from that used by synaptobrevin-2, linking its trafficking to synaptic activity levels.","evidence":"pHluorin reporters, ADBE genetic inhibition, bulk endosome purification, and di-leucine mutagenesis in neuronal cultures","pmids":["26607000"],"confidence":"High","gaps":["Adaptor protein(s) recognizing the di-leucine motif during ADBE not identified","Fate of VAMP4 after bulk endosome generation not fully traced"]},{"year":2020,"claim":"Extending VAMP4's synaptic role to Ca²⁺-dependent spontaneous excitatory transmission, and showing that high-frequency stimulation augments spontaneous release in a VAMP4-dependent manner, unified asynchronous and spontaneous release under a shared VAMP4-dependent mechanism.","evidence":"siRNA knockdown and VAMP4 mutant rescue, mEPSC/mIPSC electrophysiology, high-frequency stimulation in hippocampal neurons","pmids":["32532887"],"confidence":"Medium","gaps":["Molecular identity of the Ca²⁺ sensor coupling activity to VAMP4-mediated spontaneous release unknown","Whether VAMP4 acts at a distinct vesicle pool or a distinct release site not resolved"]},{"year":2021,"claim":"Three parallel studies in 2021 expanded VAMP4 function: (i) VAMP4 copy number on SVs regulates release probability via endolysosomal sorting during ADBE; (ii) VAMP4 mediates dendritic recycling endosome exocytosis and differentially sorts AMPAR versus TfR; (iii) VAMP4 forms a trans-SNARE complex with Stx6/Stx7/Vti1b for Golgi-to-late-endosome transport of MT1-MMP in macrophages.","evidence":"SNARE reconstitution, pHluorin imaging, endolysosomal perturbation (neurons); VAMP4 knockdown with AMPAR/TfR recycling assays and LTP electrophysiology (neurons); Co-IP of trans-SNARE complex and gelatin degradation assay (macrophages)","pmids":["33931449","34496238","34476885"],"confidence":"High","gaps":["Mechanism by which VAMP4 is selectively sorted to endolysosomes rather than recycled to SVs not defined","How VAMP4-dependent sorting separates AMPAR and TfR populations in dendrites is mechanistically unclear","Whether Stx6/Stx7/Vti1b complex operates at synapses is untested"]},{"year":null,"claim":"The Ca²⁺ sensor that drives VAMP4-dependent asynchronous and spontaneous release remains unidentified, and a structural model of the VAMP4 SNARE complex explaining the exclusion of complexin and synaptotagmin-1 is lacking.","evidence":"","pmids":[],"confidence":"High","gaps":["No crystal or cryo-EM structure of a VAMP4-containing SNARE complex","In vivo phenotype of VAMP4 knockout in mammals not reported","Relationship between presynaptic and dendritic VAMP4 pools not established"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[0,4,8,11]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[1,2,3,7,11]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[1,5,11]},{"term_id":"GO:0031410","term_label":"cytoplasmic vesicle","supporting_discovery_ids":[4,5,10]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[1,9]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[1,2,3,5,7,10,11]},{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[0,5,8,9]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[6]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[2,3,5,8]}],"complexes":["VAMP4/syntaxin-1/SNAP-25 SNARE complex","VAMP4/Stx6/Stx7/Vti1b SNARE complex","VAMP4/syntaxin-6/SNAP-23 enlargeosome SNARE complex"],"partners":["STX1A","SNAP25","STX6","STX7","VTI1B","SNAP23","AP1M1","PACS1"],"other_free_text":[]},"mechanistic_narrative":"VAMP4 is a vesicle-associated R-SNARE that functions in multiple membrane fusion events across the endomembrane system, with specialized roles in both regulated exocytosis and intracellular trafficking. Its N-terminal extension contains a di-leucine motif and acidic cluster that direct AP-1/PACS-1-dependent, clathrin-mediated recycling from the cell surface through sorting and recycling endosomes to the TGN, with casein kinase 2 phosphorylation of Ser30 enhancing AP-1 binding [PMID:14608369, PMID:12682051, PMID:17327277]. At synapses, VAMP4 forms SNARE complexes with syntaxin-1/SNAP-25 that lack complexin and synaptotagmin-1 binding, selectively driving Ca²⁺-dependent asynchronous and spontaneous neurotransmitter release; its copy number on synaptic vesicles is controlled by selective retrieval via activity-dependent bulk endocytosis and sorting to endolysosomes, thereby regulating release probability [PMID:22406549, PMID:26607000, PMID:33931449, PMID:32532887]. In non-neuronal cells, VAMP4 partners with Stx6/Stx7/Vti1b to mediate Golgi-to-late-endosome trafficking, is required for enlargeosome exocytosis, Golgi ribbon maintenance, NK-cell cytotoxic granule release, and dendritic recycling endosome exocytosis that differentially sorts AMPA receptors and transferrin receptors [PMID:34476885, PMID:18713833, PMID:23677696, PMID:21805468, PMID:34496238]."},"prefetch_data":{"uniprot":{"accession":"O75379","full_name":"Vesicle-associated membrane protein 4","aliases":[],"length_aa":141,"mass_kda":16.4,"function":"Involved in the pathway that functions to remove an inhibitor (probably synaptotagmin-4) of calcium-triggered exocytosis during the maturation of secretory granules. May be a marker for this sorting pathway that is critical for remodeling the secretory response of granule","subcellular_location":"Golgi apparatus, trans-Golgi network membrane","url":"https://www.uniprot.org/uniprotkb/O75379/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/VAMP4","classification":"Not Classified","n_dependent_lines":3,"n_total_lines":1208,"dependency_fraction":0.0024834437086092716},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000117533","cell_line_id":"CID000771","localizations":[{"compartment":"vesicles","grade":3}],"interactors":[{"gene":"VTI1A","stoichiometry":10.0},{"gene":"SNAP29","stoichiometry":4.0},{"gene":"NSF","stoichiometry":4.0},{"gene":"CLTA","stoichiometry":0.2},{"gene":"CSNK2B","stoichiometry":0.2},{"gene":"NAPA","stoichiometry":0.2},{"gene":"STX10","stoichiometry":0.2},{"gene":"STX5","stoichiometry":0.2},{"gene":"STX7","stoichiometry":0.2},{"gene":"STX8","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID000771","total_profiled":1310},"omim":[{"mim_id":"620986","title":"T-SNARE DOMAIN-CONTAINING PROTEIN 1; TSNARE1","url":"https://www.omim.org/entry/620986"},{"mim_id":"619659","title":"SYNAPTOSOME-ASSOCIATED PROTEIN 47; SNAP47","url":"https://www.omim.org/entry/619659"},{"mim_id":"619550","title":"RAB40B, MEMBER RAS ONCOGENE FAMILY; RAB40B","url":"https://www.omim.org/entry/619550"},{"mim_id":"615738","title":"VPS51 SUBUNIT OF GARP COMPLEX; VPS51","url":"https://www.omim.org/entry/615738"},{"mim_id":"606909","title":"VESICLE-ASSOCIATED MEMBRANE PROTEIN 4; VAMP4","url":"https://www.omim.org/entry/606909"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Golgi apparatus","reliability":"Approved"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/VAMP4"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"O75379","domains":[{"cath_id":"1.20.5","chopping":"51-141","consensus_level":"medium","plddt":91.0362,"start":51,"end":141}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O75379","model_url":"https://alphafold.ebi.ac.uk/files/AF-O75379-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O75379-F1-predicted_aligned_error_v6.png","plddt_mean":81.25},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=VAMP4","jax_strain_url":"https://www.jax.org/strain/search?query=VAMP4"},"sequence":{"accession":"O75379","fasta_url":"https://rest.uniprot.org/uniprotkb/O75379.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O75379/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O75379"}},"corpus_meta":[{"pmid":"22406549","id":"PMC_22406549","title":"VAMP4 directs synaptic vesicles to a pool that selectively maintains asynchronous neurotransmission.","date":"2012","source":"Nature neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/22406549","citation_count":126,"is_preprint":false},{"pmid":"17327277","id":"PMC_17327277","title":"VAMP4 cycles from the cell surface to the trans-Golgi network via sorting and recycling endosomes.","date":"2007","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/17327277","citation_count":61,"is_preprint":false},{"pmid":"26607000","id":"PMC_26607000","title":"VAMP4 Is an Essential Cargo Molecule for Activity-Dependent Bulk Endocytosis.","date":"2015","source":"Neuron","url":"https://pubmed.ncbi.nlm.nih.gov/26607000","citation_count":59,"is_preprint":false},{"pmid":"14608369","id":"PMC_14608369","title":"AP-1 recruitment to VAMP4 is modulated by phosphorylation-dependent binding of PACS-1.","date":"2003","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/14608369","citation_count":55,"is_preprint":false},{"pmid":"18713833","id":"PMC_18713833","title":"The regulated exocytosis of enlargeosomes is mediated by a SNARE machinery that includes VAMP4.","date":"2008","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/18713833","citation_count":50,"is_preprint":false},{"pmid":"15635639","id":"PMC_15635639","title":"Suicide attempt and basic mechanisms in neural conduction: relationships to the SCN8A and VAMP4 genes.","date":"2005","source":"American journal of medical genetics. Part B, Neuropsychiatric genetics : the official publication of the International Society of Psychiatric Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/15635639","citation_count":41,"is_preprint":false},{"pmid":"12682051","id":"PMC_12682051","title":"The cytoplasmic domain of Vamp4 and Vamp5 is responsible for their correct subcellular targeting: the N-terminal extenSion of VAMP4 contains a dominant autonomous targeting signal for the trans-Golgi network.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12682051","citation_count":39,"is_preprint":false},{"pmid":"21805468","id":"PMC_21805468","title":"VAMP4- and VAMP7-expressing vesicles are both required for cytotoxic granule exocytosis in NK cells.","date":"2011","source":"European journal of immunology","url":"https://pubmed.ncbi.nlm.nih.gov/21805468","citation_count":32,"is_preprint":false},{"pmid":"23677696","id":"PMC_23677696","title":"VAMP4 is required to maintain the ribbon structure of the Golgi apparatus.","date":"2013","source":"Molecular and cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23677696","citation_count":31,"is_preprint":false},{"pmid":"33931449","id":"PMC_33931449","title":"Control of synaptic vesicle release probability via VAMP4 targeting to endolysosomes.","date":"2021","source":"Science advances","url":"https://pubmed.ncbi.nlm.nih.gov/33931449","citation_count":30,"is_preprint":false},{"pmid":"32532887","id":"PMC_32532887","title":"VAMP4 Maintains a Ca2+-Sensitive Pool of Spontaneously Recycling Synaptic Vesicles.","date":"2020","source":"The Journal of neuroscience : the official journal of the Society for Neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/32532887","citation_count":24,"is_preprint":false},{"pmid":"32873436","id":"PMC_32873436","title":"Analysis of DNM3 and VAMP4 as genetic modifiers of LRRK2 Parkinson's disease.","date":"2020","source":"Neurobiology of aging","url":"https://pubmed.ncbi.nlm.nih.gov/32873436","citation_count":22,"is_preprint":false},{"pmid":"34496238","id":"PMC_34496238","title":"The vSNAREs VAMP2 and VAMP4 control recycling and intracellular sorting of post-synaptic receptors in neuronal dendrites.","date":"2021","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/34496238","citation_count":19,"is_preprint":false},{"pmid":"34476885","id":"PMC_34476885","title":"The trans-SNARE complex VAMP4/Stx6/Stx7/Vti1b is a key regulator of Golgi to late endosome MT1-MMP transport in macrophages.","date":"2021","source":"Traffic (Copenhagen, Denmark)","url":"https://pubmed.ncbi.nlm.nih.gov/34476885","citation_count":12,"is_preprint":false},{"pmid":"41460344","id":"PMC_41460344","title":"VAMP4 in hypoxic adipose stem cell exosomes alleviates ischemia-reperfusion injury.","date":"2025","source":"Cellular and molecular life sciences : CMLS","url":"https://pubmed.ncbi.nlm.nih.gov/41460344","citation_count":0,"is_preprint":false},{"pmid":"41979085","id":"PMC_41979085","title":"VAMP4/STX8 Mediate the Autophagic Secretion of Mitochondria and Promote TAMs Polarization in HNSCC.","date":"2026","source":"Journal of extracellular vesicles","url":"https://pubmed.ncbi.nlm.nih.gov/41979085","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":8756,"output_tokens":3159,"usd":0.036826},"stage2":{"model":"claude-opus-4-6","input_tokens":6510,"output_tokens":3059,"usd":0.163538},"total_usd":0.200364,"stage1_batch_id":"msgbatch_01BparvgRZ9S2LMidvaoo86K","stage2_batch_id":"msgbatch_01NkBfv9SVZWthhS7j6mU6G3","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2012,\n      \"finding\": \"VAMP4 forms a stable SNARE complex with syntaxin-1 and SNAP-25 that does not interact with complexins or synaptotagmin-1 (proteins essential for synchronous neurotransmission), and this distinct complex selectively maintains Ca2+-dependent asynchronous neurotransmitter release at inhibitory nerve terminals. Up- or downregulation of VAMP4 causes a correlated change in asynchronous release. VAMP4 and synaptobrevin2 traffic independently with minimal overlap.\",\n      \"method\": \"Biochemical SNARE complex pulldown, up/downregulation of VAMP4 in neurons with electrophysiological readout, optical imaging of individual synapses\",\n      \"journal\": \"Nature neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — multiple orthogonal methods (biochemistry, electrophysiology, imaging), replicated across conditions\",\n      \"pmids\": [\"22406549\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"VAMP4 cycles from the cell surface to the TGN via clathrin-dependent endocytosis through sorting and then recycling endosomes (not late endosomes). The di-leucine motif of the TGN-targeting signal is important for internalization, while the acidic cluster is crucial for delivery from endosome to TGN.\",\n      \"method\": \"Live-cell imaging of VAMP4-EGFP, antibody uptake assays, pharmacological and thermal perturbation, site-directed mutagenesis\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods including mutagenesis and pharmacological perturbation in a single study\",\n      \"pmids\": [\"17327277\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"VAMP4 binds to AP-1 subunit mu1a (but not mu1b or GGAs) via its dileucine motif (Leu25,26) and Ser20. Phosphorylation of Ser30 in the acidic cluster by casein kinase 2 enhances AP-1 binding via PACS-1. Ablation of both the dileucine motif and Ser30, or dominant-negative PACS-1, causes dramatic mislocalization of VAMP4 in AtT20 cells.\",\n      \"method\": \"Co-immunoprecipitation, site-directed mutagenesis, dominant-negative PACS-1 expression, fluorescence microscopy\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — mutagenesis combined with binding assays and functional mislocalization readout\",\n      \"pmids\": [\"14608369\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"The N-terminal 51-residue extension of VAMP4 (containing a di-leucine motif followed by two acidic clusters) is a dominant and autonomous targeting signal sufficient to redirect VAMP5 to the TGN. The di-leucine motif and the second acidic cluster are essential for TGN targeting.\",\n      \"method\": \"Domain-swap chimeras between VAMP4 and VAMP5, C-terminal EGFP tagging, deletion and site-directed mutagenesis, fluorescence microscopy\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — domain-swap chimeras plus site-directed mutagenesis with clear subcellular localization readout\",\n      \"pmids\": [\"12682051\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"VAMP4 is localized in enlargeosome membranes and is a required component of the SNARE machinery (together with syntaxin-6 and SNAP23) mediating regulated exocytosis of enlargeosomes. Anti-VAMP4 antibody microinjection and VAMP4 siRNA both inhibit enlargeosome exocytosis.\",\n      \"method\": \"Immunolocalization, anti-VAMP4 antibody microinjection, siRNA knockdown, capacitance measurements, VAMP4-GFP live imaging\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple methods (electrophysiology, antibody inhibition, siRNA, live imaging) converging on same conclusion\",\n      \"pmids\": [\"18713833\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"VAMP4 is an essential cargo molecule for activity-dependent bulk endocytosis (ADBE) at synapses, with a cytoplasmic di-leucine motif being critical for this role. VAMP4 is selectively retrieved by ADBE and is enriched in bulk endosomes; inhibiting ADBE specifically perturbs VAMP4-pHluorin retrieval but not other SV cargo reporters.\",\n      \"method\": \"pH-sensitive pHluorin reporters in neuronal cultures, genetic inhibition of ADBE, purification of bulk endosomes with western blotting, di-leucine motif mutagenesis\",\n      \"journal\": \"Neuron\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods including functional reporters, biochemical fractionation, and mutagenesis\",\n      \"pmids\": [\"26607000\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"In NK cells, VAMP4 colocalizes with lytic granules during cytotoxic interactions and is required for cytotoxic granule exocytosis and NK cell cytotoxic activity. VAMP4 knockdown inhibits lytic granule release but does not affect IFN-γ secretion, distinguishing its function from VAMP7.\",\n      \"method\": \"Immunofluorescence colocalization, siRNA knockdown, cytotoxicity assays in YTS cells and peripheral NK cells\",\n      \"journal\": \"European journal of immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — siRNA knockdown with specific functional readout (granule exocytosis vs IFN-γ secretion)\",\n      \"pmids\": [\"21805468\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"VAMP4 is required to maintain the Golgi ribbon structure. Depletion of VAMP4 by RNAi causes Golgi ribbon fragmentation (shortened stacks remaining in juxtanuclear area) without disrupting anterograde trafficking or microtubule arrays. Depletion of VAMP4 cognate SNARE partners (syntaxin 6, syntaxin 16, Vti1a) similarly disrupts the Golgi ribbon, implicating the VAMP4-containing SNARE complex in retrograde trafficking needed for Golgi integrity.\",\n      \"method\": \"RNAi knockdown in HeLa cells, electron microscopy, immunofluorescence, anterograde trafficking assays\",\n      \"journal\": \"Molecular and cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — RNAi with multiple readouts (EM, IF, trafficking assays) in a single study\",\n      \"pmids\": [\"23677696\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"VAMP4 copy number on synaptic vesicles regulates release probability (Pr): VAMP4 has reduced ability to form efficient SNARE complexes with canonical plasma membrane SNAREs, and its high synaptic turnover is coupled to selective sorting to endolysosomes during activity-dependent bulk endocytosis. Disruption of endolysosomal trafficking increases VAMP4 abundance in the SV pool and inhibits SV fusion.\",\n      \"method\": \"SNARE complex reconstitution assay, fluorescence imaging, endolysosomal trafficking perturbation, pHluorin reporters, mass spectrometry\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — in vitro SNARE complex assay combined with live imaging and trafficking perturbation experiments\",\n      \"pmids\": [\"33931449\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"VAMP4 is required for Ca2+-dependent spontaneous excitatory neurotransmission in hippocampal neurons. Key residues controlling VAMP4 retrieval and functional clathrin-mediated trafficking are essential for maintaining VAMP4-mediated spontaneous release. High-frequency stimulation augments Ca2+-sensitive spontaneous release for up to 30 min in a VAMP4-dependent manner, linking asynchronous and spontaneous release.\",\n      \"method\": \"siRNA knockdown and rescue with VAMP4 mutants in hippocampal neurons, electrophysiology (mEPSC/mIPSC recording), high-frequency stimulation protocols\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — electrophysiology with mutagenesis in a single study\",\n      \"pmids\": [\"32532887\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"VAMP4 is the primary vesicular SNARE mediating dendritic recycling endosome exocytosis. VAMP4 knockdown decreases transferrin receptor (TfR) recycling but paradoxically increases AMPA receptor (AMPAR) recycling and synaptic transmission, occluding LTP, revealing that VAMP4 sorts AMPARs and TfRs into separate endosomal populations.\",\n      \"method\": \"VAMP4 knockdown in neurons, live imaging of VAMP4-labeled organelles, electrophysiology (LTP, AMPAR-mediated transmission), TfR recycling assays\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — knockdown with multiple functional readouts (imaging, electrophysiology, receptor recycling)\",\n      \"pmids\": [\"34496238\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"VAMP4 on Golgi-derived vesicles forms a trans-SNARE complex with the Q-SNARE complex Stx6/Stx7/Vti1b to mediate fusion with late endosomes, regulating transport of MT1-MMP from Golgi to late endosomes and subsequently to the cell surface in macrophages. Depletion of any SNARE in this complex reduces surface MT1-MMP and gelatin degradation.\",\n      \"method\": \"Fixed and live imaging, co-immunoprecipitation (trans-SNARE complex), siRNA knockdown, gelatin degradation assay\",\n      \"journal\": \"Traffic\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — Co-IP of trans-SNARE complex combined with functional knockdown assays\",\n      \"pmids\": [\"34476885\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"VAMP4 is a TGN-enriched R-SNARE whose N-terminal di-leucine/acidic-cluster motif directs it to the TGN via AP-1/PACS-1-dependent, clathrin-mediated recycling from the cell surface through sorting and recycling endosomes; at synapses, it forms SNARE complexes that lack synaptotagmin-1 and complexin binding, driving asynchronous and Ca2+-sensitive spontaneous neurotransmission, while its selective sorting to endolysosomes via activity-dependent bulk endocytosis controls its copy number on synaptic vesicles and thereby regulates release probability; in non-neuronal cells it partners with Stx6/Stx7/Vti1b for Golgi-to-late-endosome trafficking and is required for enlargeosome exocytosis, Golgi ribbon maintenance, and NK-cell cytotoxic granule exocytosis.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"VAMP4 is a vesicle-associated R-SNARE that functions in multiple membrane fusion events across the endomembrane system, with specialized roles in both regulated exocytosis and intracellular trafficking. Its N-terminal extension contains a di-leucine motif and acidic cluster that direct AP-1/PACS-1-dependent, clathrin-mediated recycling from the cell surface through sorting and recycling endosomes to the TGN, with casein kinase 2 phosphorylation of Ser30 enhancing AP-1 binding [PMID:14608369, PMID:12682051, PMID:17327277]. At synapses, VAMP4 forms SNARE complexes with syntaxin-1/SNAP-25 that lack complexin and synaptotagmin-1 binding, selectively driving Ca²⁺-dependent asynchronous and spontaneous neurotransmitter release; its copy number on synaptic vesicles is controlled by selective retrieval via activity-dependent bulk endocytosis and sorting to endolysosomes, thereby regulating release probability [PMID:22406549, PMID:26607000, PMID:33931449, PMID:32532887]. In non-neuronal cells, VAMP4 partners with Stx6/Stx7/Vti1b to mediate Golgi-to-late-endosome trafficking, is required for enlargeosome exocytosis, Golgi ribbon maintenance, NK-cell cytotoxic granule release, and dendritic recycling endosome exocytosis that differentially sorts AMPA receptors and transferrin receptors [PMID:34476885, PMID:18713833, PMID:23677696, PMID:21805468, PMID:34496238].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Identification of the N-terminal di-leucine/acidic-cluster motif as a dominant TGN-targeting signal established the structural basis for VAMP4's steady-state localization, answering how VAMP4 is distinguished from other VAMPs that lack this extension.\",\n      \"evidence\": \"Domain-swap chimeras between VAMP4 and VAMP5, site-directed mutagenesis with fluorescence microscopy in COS cells; parallel AP-1 binding assays and PACS-1 dominant-negative experiments in AtT20 cells\",\n      \"pmids\": [\"12682051\", \"14608369\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis for CK2 phosphorylation-dependent enhancement of AP-1 binding not resolved\", \"In vivo relevance of TGN targeting in neuronal vs. non-neuronal contexts not compared\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Tracing VAMP4's full itinerary from the plasma membrane through sorting and recycling endosomes back to the TGN resolved the recycling route and assigned distinct roles to the di-leucine motif (internalization) versus the acidic cluster (endosome-to-TGN delivery).\",\n      \"evidence\": \"Live-cell imaging of VAMP4-EGFP, antibody uptake assays, temperature blocks, and mutagenesis in HeLa cells\",\n      \"pmids\": [\"17327277\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Coat/adaptor complexes acting at the endosome-to-TGN step not fully identified\", \"Kinetic parameters of recycling not quantified\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Demonstrating that VAMP4 is a required SNARE for enlargeosome exocytosis (with syntaxin-6 and SNAP23) established VAMP4's first known role in regulated secretion in non-neuronal cells.\",\n      \"evidence\": \"Anti-VAMP4 antibody microinjection, siRNA knockdown, capacitance measurements, and live imaging in U2OS cells\",\n      \"pmids\": [\"18713833\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How VAMP4 is recruited to enlargeosomes is unknown\", \"Whether VAMP4 participates in the Ca²⁺ sensor interaction for enlargeosome fusion is unclear\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Showing that VAMP4 knockdown specifically inhibits cytotoxic granule exocytosis but not IFN-γ secretion in NK cells demonstrated cargo-selective SNARE function in immune effector cells.\",\n      \"evidence\": \"siRNA knockdown, immunofluorescence, and cytotoxicity assays in YTS and primary NK cells\",\n      \"pmids\": [\"21805468\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"SNARE partners for VAMP4 at the NK cell lytic granule not identified\", \"Single knockdown study without rescue experiment\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Discovery that VAMP4 forms SNARE complexes lacking complexin and synaptotagmin-1 binding and selectively supports asynchronous neurotransmitter release fundamentally established a molecularly distinct fusion machinery for asynchronous versus synchronous transmission.\",\n      \"evidence\": \"Biochemical SNARE complex pulldown, electrophysiology and optical imaging with VAMP4 up/downregulation in cultured hippocampal neurons\",\n      \"pmids\": [\"22406549\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Ca²⁺ sensor driving VAMP4-dependent asynchronous release not identified\", \"Whether VAMP4 SNARE complexes operate at excitatory synapses not tested in this study\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Demonstrating that VAMP4 depletion fragments the Golgi ribbon without disrupting anterograde transport revealed a role in retrograde trafficking required for Golgi structural integrity, mediated by a complex including syntaxin-6, syntaxin-16, and Vti1a.\",\n      \"evidence\": \"RNAi knockdown in HeLa cells with electron microscopy, immunofluorescence, and anterograde trafficking assays\",\n      \"pmids\": [\"23677696\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Cargo carried by VAMP4-dependent retrograde pathway not identified\", \"Whether Golgi fragmentation reflects direct SNARE function or indirect effect not fully resolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Identifying VAMP4 as a selective cargo of activity-dependent bulk endocytosis (ADBE) via its di-leucine motif resolved how VAMP4 is retrieved from the presynaptic surface by a pathway distinct from that used by synaptobrevin-2, linking its trafficking to synaptic activity levels.\",\n      \"evidence\": \"pHluorin reporters, ADBE genetic inhibition, bulk endosome purification, and di-leucine mutagenesis in neuronal cultures\",\n      \"pmids\": [\"26607000\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Adaptor protein(s) recognizing the di-leucine motif during ADBE not identified\", \"Fate of VAMP4 after bulk endosome generation not fully traced\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Extending VAMP4's synaptic role to Ca²⁺-dependent spontaneous excitatory transmission, and showing that high-frequency stimulation augments spontaneous release in a VAMP4-dependent manner, unified asynchronous and spontaneous release under a shared VAMP4-dependent mechanism.\",\n      \"evidence\": \"siRNA knockdown and VAMP4 mutant rescue, mEPSC/mIPSC electrophysiology, high-frequency stimulation in hippocampal neurons\",\n      \"pmids\": [\"32532887\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular identity of the Ca²⁺ sensor coupling activity to VAMP4-mediated spontaneous release unknown\", \"Whether VAMP4 acts at a distinct vesicle pool or a distinct release site not resolved\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Three parallel studies in 2021 expanded VAMP4 function: (i) VAMP4 copy number on SVs regulates release probability via endolysosomal sorting during ADBE; (ii) VAMP4 mediates dendritic recycling endosome exocytosis and differentially sorts AMPAR versus TfR; (iii) VAMP4 forms a trans-SNARE complex with Stx6/Stx7/Vti1b for Golgi-to-late-endosome transport of MT1-MMP in macrophages.\",\n      \"evidence\": \"SNARE reconstitution, pHluorin imaging, endolysosomal perturbation (neurons); VAMP4 knockdown with AMPAR/TfR recycling assays and LTP electrophysiology (neurons); Co-IP of trans-SNARE complex and gelatin degradation assay (macrophages)\",\n      \"pmids\": [\"33931449\", \"34496238\", \"34476885\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which VAMP4 is selectively sorted to endolysosomes rather than recycled to SVs not defined\", \"How VAMP4-dependent sorting separates AMPAR and TfR populations in dendrites is mechanistically unclear\", \"Whether Stx6/Stx7/Vti1b complex operates at synapses is untested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The Ca²⁺ sensor that drives VAMP4-dependent asynchronous and spontaneous release remains unidentified, and a structural model of the VAMP4 SNARE complex explaining the exclusion of complexin and synaptotagmin-1 is lacking.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No crystal or cryo-EM structure of a VAMP4-containing SNARE complex\", \"In vivo phenotype of VAMP4 knockout in mammals not reported\", \"Relationship between presynaptic and dendritic VAMP4 pools not established\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 4, 8, 11]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [1, 2, 3, 7, 11]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [1, 5, 11]},\n      {\"term_id\": \"GO:0031410\", \"supporting_discovery_ids\": [4, 5, 10]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [1, 9]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [1, 2, 3, 5, 7, 10, 11]},\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [0, 5, 8, 9]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [6]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [2, 3, 5, 8]}\n    ],\n    \"complexes\": [\n      \"VAMP4/syntaxin-1/SNAP-25 SNARE complex\",\n      \"VAMP4/Stx6/Stx7/Vti1b SNARE complex\",\n      \"VAMP4/syntaxin-6/SNAP-23 enlargeosome SNARE complex\"\n    ],\n    \"partners\": [\n      \"STX1A\",\n      \"SNAP25\",\n      \"STX6\",\n      \"STX7\",\n      \"VTI1B\",\n      \"SNAP23\",\n      \"AP1M1\",\n      \"PACS1\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}