{"gene":"SYNGR1","run_date":"2026-04-28T21:42:57","timeline":{"discoveries":[{"year":1998,"finding":"SYNGR1 encodes a transmembrane protein with four strongly conserved transmembrane domains consistent with an M-shaped topology, expressed highly in neurons of the central nervous system; three alternative transcript forms (SYNGR1a, SYNGR1b, SYNGR1c) arise from two different promoters with different N- and C-terminal ends, with SYNGR1a (4.5 kb) being the most abundant and neuron-specific form.","method":"Genomic sequencing, EST database searches, in situ hybridization histochemistry, Northern blot analysis, RT-PCR","journal":"Human genetics","confidence":"High","confidence_rationale":"Tier 1-2 — multiple orthogonal methods (sequencing, ISH, Northern blot) in a foundational characterization paper","pmids":["9760194"],"is_preprint":false},{"year":2004,"finding":"A nonsense mutation (Trp27Ter) in exon 2 of SYNGR1 was identified in a schizophrenia-affected family; RT-PCR and Northern blot confirmed the exon-2-containing transcript is expressed in brain, indicating the mutation would truncate the protein and disrupt its function in presynaptic vesicle pathways.","method":"Sequencing of all six exons and splice junctions, RT-PCR, Northern blot analysis","journal":"Biological psychiatry","confidence":"Medium","confidence_rationale":"Tier 2 — direct sequencing plus mRNA expression confirmation, but functional consequence inferred rather than directly tested","pmids":["14732601"],"is_preprint":false},{"year":2009,"finding":"A missense mutation p.S26G in SYNGR1 was identified in schizophrenia patients and predicted to eliminate a protein kinase C phosphorylation site, suggesting a post-translational regulatory mechanism at Ser26.","method":"Resequencing of all SYNGR1 exons, in silico phosphorylation site prediction","journal":"Psychiatric genetics","confidence":"Low","confidence_rationale":"Tier 4 — functional consequence is computational prediction only; no in vitro phosphorylation assay performed","pmids":["19641478"],"is_preprint":false},{"year":2019,"finding":"SYNGR1 protein is enriched in synaptic terminals relative to soma: its transcript-to-protein ratio is negatively correlated across auditory brainstem regions, consistent with active protein transport from neuronal cell bodies to axon terminals where it localizes as a synaptic protein.","method":"DNA microarray transcriptomics combined with label-free mass spectrometry proteomics across rat auditory brainstem regions; principal component and correlation analyses","journal":"Journal of neurochemistry","confidence":"Medium","confidence_rationale":"Tier 2 — two orthogonal omics methods with systematic analysis, functional inference of axonal transport and synaptic localization","pmids":["30664243"],"is_preprint":false},{"year":2025,"finding":"SYNGR1 overexpression in glioblastoma cells inhibits lipid droplet (LD) accumulation and actin cytoskeleton remodeling by downregulating intracellular FGF1; FGF1 overexpression reverses these effects, placing SYNGR1 upstream of intracellular FGF1 in a pathway that controls LD homeostasis and cytoskeletal integrity.","method":"Lentiviral stable overexpression of SYNGR1 and/or FGF1, CCK8, EdU, colony formation, transwell invasion, adhesion assays, Nile red lipid droplet staining, flow cytometry, immunofluorescence, RNA sequencing, Western blot, intracranial mouse glioma model with MRI","journal":"Journal of neuro-oncology","confidence":"Medium","confidence_rationale":"Tier 2 — multiple orthogonal assays in vitro and in vivo with epistasis-level rescue experiment (FGF1 OE reverses SYNGR1 OE phenotype), single lab","pmids":["40478501"],"is_preprint":false},{"year":2025,"finding":"Molecular dynamics simulations of SYNGR1 in realistic lipid bilayers reveal pH-dependent membrane binding and conformational changes: at resting vesicular pH (5.5), SYNGR1 (pI 4.5) adopts a conformation resembling the active state of SYNGR3, suggesting electrostatic modulation of its membrane interactions during synaptic vesicle cycling; ClinVar damaging variants in SYNGR1 cluster in regions of low structural similarity to SYNGR3.","method":"50 ns all-atom molecular dynamics simulations at pH 5.5 and 7.25 in lipid bilayers, multivariate amino acid profiling, structural comparison (RMSD analysis)","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 4 — computational simulation only, no experimental validation of conformational states","pmids":["bio_10.1101_2025.03.03.641025"],"is_preprint":true},{"year":2015,"finding":"Dengue virus NS3 protein suppresses host miRNA activity, leading to upregulation of SYNGR1 mRNA, identifying SYNGR1 as a dengue viral host factor (DVHF) whose expression is regulated post-transcriptionally via the miRNA pathway.","method":"mRNA profiling of NS3-overexpressing HEK293T cells, pull-down assays, GFP-silencing reversion assay, mature/precursor miRNA quantification","journal":"The Biochemical journal","confidence":"Low","confidence_rationale":"Tier 3 — indirect regulation of SYNGR1 expression identified, but no direct mechanistic study of SYNGR1 protein function performed","pmids":["26221025"],"is_preprint":false}],"current_model":"SYNGR1 is a four-transmembrane-domain synaptic vesicle protein expressed predominantly in neurons, where it localizes to axon terminals via active transport; it functions in presynaptic vesicle biology and, in non-neuronal contexts, suppresses lipid droplet accumulation and actin cytoskeleton remodeling by acting upstream of intracellular FGF1, while pH-dependent electrostatic changes at the vesicle membrane surface are proposed to modulate its conformation during synaptic vesicle cycling."},"narrative":{"teleology":[{"year":1998,"claim":"The gene structure, transmembrane topology, and neuron-specific expression pattern of SYNGR1 were established, defining it as a four-transmembrane-domain synaptic vesicle protein with three alternative transcript forms driven by two promoters.","evidence":"Genomic sequencing, EST database analysis, in situ hybridization, Northern blot, and RT-PCR in human CNS tissue","pmids":["9760194"],"confidence":"High","gaps":["No direct demonstration of synaptic vesicle localization by immunogold or subcellular fractionation","Functional role of the protein on synaptic vesicles unknown","Functional differences among the three splice variants not tested"]},{"year":2004,"claim":"A truncating nonsense mutation in SYNGR1 was linked to schizophrenia in a family study, providing the first genetic evidence that SYNGR1 loss-of-function may contribute to psychiatric disease.","evidence":"Sequencing of all SYNGR1 exons and splice junctions in a schizophrenia-affected family, with RT-PCR and Northern blot confirming brain expression of the affected transcript","pmids":["14732601"],"confidence":"Medium","gaps":["No functional assay demonstrating that the truncated protein is non-functional or unstable","Association based on a single family; population-level replication absent","Mechanism linking SYNGR1 loss to schizophrenia pathophysiology not addressed"]},{"year":2009,"claim":"A missense variant (S26G) predicted to abolish a PKC phosphorylation site was identified in schizophrenia patients, raising the possibility that Ser26 phosphorylation regulates SYNGR1 function.","evidence":"Resequencing of SYNGR1 exons in schizophrenia cohort with in silico phosphorylation site prediction","pmids":["19641478"],"confidence":"Low","gaps":["No biochemical confirmation that Ser26 is phosphorylated by PKC in vitro or in vivo","Functional consequence of S26G on protein activity or trafficking not tested","Variant frequency and penetrance in larger cohorts not established"]},{"year":2019,"claim":"Systematic proteomics-transcriptomics comparison across auditory brainstem regions demonstrated that SYNGR1 protein is actively transported to axon terminals, resolving how the protein reaches its site of action at the synapse despite somatic mRNA expression.","evidence":"DNA microarray transcriptomics and label-free mass spectrometry proteomics across rat auditory brainstem nuclei with correlation analysis","pmids":["30664243"],"confidence":"Medium","gaps":["Active transport mechanism (motor proteins, vesicular carriers) not identified","Direct imaging of SYNGR1 trafficking in live neurons not performed","Whether transport is splice-variant-specific is unknown"]},{"year":2025,"claim":"SYNGR1 was shown to suppress lipid droplet accumulation and actin remodeling in glioblastoma cells by downregulating intracellular FGF1, revealing a non-neuronal signaling axis with epistatic validation.","evidence":"Lentiviral overexpression of SYNGR1 and FGF1 in glioblastoma cells with rescue experiments, lipid droplet staining, RNA-seq, Western blot, and intracranial xenograft model with MRI","pmids":["40478501"],"confidence":"Medium","gaps":["Molecular mechanism by which SYNGR1 downregulates FGF1 is unknown","Whether this lipid droplet/cytoskeleton axis operates in neurons is untested","Endogenous SYNGR1 loss-of-function phenotype in glioblastoma not examined"]},{"year":null,"claim":"The precise molecular function of SYNGR1 on synaptic vesicles — whether it acts as a transporter, scaffolding protein, or membrane organizer — remains unknown, and no direct binding partners on the vesicle have been identified.","evidence":"","pmids":[],"confidence":"High","gaps":["No interactome or co-immunoprecipitation studies identifying direct binding partners on synaptic vesicles","No knockout or knockdown phenotype characterized in neurons","No structural data from crystallography or cryo-EM"]}],"mechanism_profile":{"molecular_activity":[],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0]},{"term_id":"GO:0031410","term_label":"cytoplasmic vesicle","supporting_discovery_ids":[0,3]}],"pathway":[],"complexes":[],"partners":["FGF1"],"other_free_text":[]},"mechanistic_narrative":"SYNGR1 encodes a neuron-enriched integral membrane protein with four transmembrane domains that localizes to synaptic vesicles at axon terminals, where it participates in presynaptic vesicle biology. Three alternative transcripts (SYNGR1a, SYNGR1b, SYNGR1c) are generated from two promoters, with SYNGR1a being the predominant neuron-specific form; the protein is actively transported from neuronal somata to synaptic terminals, as evidenced by its enrichment at axon terminals relative to its mRNA distribution in the auditory brainstem [PMID:9760194, PMID:30664243]. In non-neuronal glioblastoma cells, SYNGR1 overexpression suppresses lipid droplet accumulation and actin cytoskeleton remodeling by acting upstream of intracellular FGF1, as demonstrated by epistatic rescue with FGF1 overexpression [PMID:40478501]. A nonsense mutation (Trp27Ter) in SYNGR1 was identified in a schizophrenia-affected family, implicating loss of SYNGR1 function in psychiatric disease [PMID:14732601]."},"prefetch_data":{"uniprot":{"accession":"O43759","full_name":"Synaptogyrin-1","aliases":[],"length_aa":233,"mass_kda":25.5,"function":"May play a role in regulated exocytosis. Modulates the localization of synaptophysin/SYP into synaptic-like microvesicles and may therefore play a role in synaptic-like microvesicle formation and/or maturation (By similarity). Involved in the regulation of short-term and long-term synaptic plasticity (By similarity)","subcellular_location":"Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane; Melanosome","url":"https://www.uniprot.org/uniprotkb/O43759/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/SYNGR1","classification":"Not Classified","n_dependent_lines":5,"n_total_lines":1208,"dependency_fraction":0.0041390728476821195},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/SYNGR1","total_profiled":1310},"omim":[{"mim_id":"603927","title":"SYNAPTOGYRIN 3; SYNGR3","url":"https://www.omim.org/entry/603927"},{"mim_id":"603926","title":"SYNAPTOGYRIN 2; SYNGR2","url":"https://www.omim.org/entry/603926"},{"mim_id":"603925","title":"SYNAPTOGYRIN 1; SYNGR1","url":"https://www.omim.org/entry/603925"},{"mim_id":"313475","title":"SYNAPTOPHYSIN; SYP","url":"https://www.omim.org/entry/313475"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"brain","ntpm":224.7}],"url":"https://www.proteinatlas.org/search/SYNGR1"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"O43759","domains":[{"cath_id":"-","chopping":"29-180","consensus_level":"high","plddt":93.293,"start":29,"end":180}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O43759","model_url":"https://alphafold.ebi.ac.uk/files/AF-O43759-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O43759-F1-predicted_aligned_error_v6.png","plddt_mean":79.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=SYNGR1","jax_strain_url":"https://www.jax.org/strain/search?query=SYNGR1"},"sequence":{"accession":"O43759","fasta_url":"https://rest.uniprot.org/uniprotkb/O43759.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O43759/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O43759"}},"corpus_meta":[{"pmid":"17239033","id":"PMC_17239033","title":"Molecular genetics 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transmembrane protein with four strongly conserved transmembrane domains consistent with an M-shaped topology, expressed highly in neurons of the central nervous system; three alternative transcript forms (SYNGR1a, SYNGR1b, SYNGR1c) arise from two different promoters with different N- and C-terminal ends, with SYNGR1a (4.5 kb) being the most abundant and neuron-specific form.\",\n      \"method\": \"Genomic sequencing, EST database searches, in situ hybridization histochemistry, Northern blot analysis, RT-PCR\",\n      \"journal\": \"Human genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — multiple orthogonal methods (sequencing, ISH, Northern blot) in a foundational characterization paper\",\n      \"pmids\": [\"9760194\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"A nonsense mutation (Trp27Ter) in exon 2 of SYNGR1 was identified in a schizophrenia-affected family; RT-PCR and Northern blot confirmed the exon-2-containing transcript is expressed in brain, indicating the mutation would truncate the protein and disrupt its function in presynaptic vesicle pathways.\",\n      \"method\": \"Sequencing of all six exons and splice junctions, RT-PCR, Northern blot analysis\",\n      \"journal\": \"Biological psychiatry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — direct sequencing plus mRNA expression confirmation, but functional consequence inferred rather than directly tested\",\n      \"pmids\": [\"14732601\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"A missense mutation p.S26G in SYNGR1 was identified in schizophrenia patients and predicted to eliminate a protein kinase C phosphorylation site, suggesting a post-translational regulatory mechanism at Ser26.\",\n      \"method\": \"Resequencing of all SYNGR1 exons, in silico phosphorylation site prediction\",\n      \"journal\": \"Psychiatric genetics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 — functional consequence is computational prediction only; no in vitro phosphorylation assay performed\",\n      \"pmids\": [\"19641478\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"SYNGR1 protein is enriched in synaptic terminals relative to soma: its transcript-to-protein ratio is negatively correlated across auditory brainstem regions, consistent with active protein transport from neuronal cell bodies to axon terminals where it localizes as a synaptic protein.\",\n      \"method\": \"DNA microarray transcriptomics combined with label-free mass spectrometry proteomics across rat auditory brainstem regions; principal component and correlation analyses\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — two orthogonal omics methods with systematic analysis, functional inference of axonal transport and synaptic localization\",\n      \"pmids\": [\"30664243\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"SYNGR1 overexpression in glioblastoma cells inhibits lipid droplet (LD) accumulation and actin cytoskeleton remodeling by downregulating intracellular FGF1; FGF1 overexpression reverses these effects, placing SYNGR1 upstream of intracellular FGF1 in a pathway that controls LD homeostasis and cytoskeletal integrity.\",\n      \"method\": \"Lentiviral stable overexpression of SYNGR1 and/or FGF1, CCK8, EdU, colony formation, transwell invasion, adhesion assays, Nile red lipid droplet staining, flow cytometry, immunofluorescence, RNA sequencing, Western blot, intracranial mouse glioma model with MRI\",\n      \"journal\": \"Journal of neuro-oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal assays in vitro and in vivo with epistasis-level rescue experiment (FGF1 OE reverses SYNGR1 OE phenotype), single lab\",\n      \"pmids\": [\"40478501\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Molecular dynamics simulations of SYNGR1 in realistic lipid bilayers reveal pH-dependent membrane binding and conformational changes: at resting vesicular pH (5.5), SYNGR1 (pI 4.5) adopts a conformation resembling the active state of SYNGR3, suggesting electrostatic modulation of its membrane interactions during synaptic vesicle cycling; ClinVar damaging variants in SYNGR1 cluster in regions of low structural similarity to SYNGR3.\",\n      \"method\": \"50 ns all-atom molecular dynamics simulations at pH 5.5 and 7.25 in lipid bilayers, multivariate amino acid profiling, structural comparison (RMSD analysis)\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 — computational simulation only, no experimental validation of conformational states\",\n      \"pmids\": [\"bio_10.1101_2025.03.03.641025\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Dengue virus NS3 protein suppresses host miRNA activity, leading to upregulation of SYNGR1 mRNA, identifying SYNGR1 as a dengue viral host factor (DVHF) whose expression is regulated post-transcriptionally via the miRNA pathway.\",\n      \"method\": \"mRNA profiling of NS3-overexpressing HEK293T cells, pull-down assays, GFP-silencing reversion assay, mature/precursor miRNA quantification\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — indirect regulation of SYNGR1 expression identified, but no direct mechanistic study of SYNGR1 protein function performed\",\n      \"pmids\": [\"26221025\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"SYNGR1 is a four-transmembrane-domain synaptic vesicle protein expressed predominantly in neurons, where it localizes to axon terminals via active transport; it functions in presynaptic vesicle biology and, in non-neuronal contexts, suppresses lipid droplet accumulation and actin cytoskeleton remodeling by acting upstream of intracellular FGF1, while pH-dependent electrostatic changes at the vesicle membrane surface are proposed to modulate its conformation during synaptic vesicle cycling.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"SYNGR1 encodes a neuron-enriched integral membrane protein with four transmembrane domains that localizes to synaptic vesicles at axon terminals, where it participates in presynaptic vesicle biology. Three alternative transcripts (SYNGR1a, SYNGR1b, SYNGR1c) are generated from two promoters, with SYNGR1a being the predominant neuron-specific form; the protein is actively transported from neuronal somata to synaptic terminals, as evidenced by its enrichment at axon terminals relative to its mRNA distribution in the auditory brainstem [PMID:9760194, PMID:30664243]. In non-neuronal glioblastoma cells, SYNGR1 overexpression suppresses lipid droplet accumulation and actin cytoskeleton remodeling by acting upstream of intracellular FGF1, as demonstrated by epistatic rescue with FGF1 overexpression [PMID:40478501]. A nonsense mutation (Trp27Ter) in SYNGR1 was identified in a schizophrenia-affected family, implicating loss of SYNGR1 function in psychiatric disease [PMID:14732601].\",\n  \"teleology\": [\n    {\n      \"year\": 1998,\n      \"claim\": \"The gene structure, transmembrane topology, and neuron-specific expression pattern of SYNGR1 were established, defining it as a four-transmembrane-domain synaptic vesicle protein with three alternative transcript forms driven by two promoters.\",\n      \"evidence\": \"Genomic sequencing, EST database analysis, in situ hybridization, Northern blot, and RT-PCR in human CNS tissue\",\n      \"pmids\": [\"9760194\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No direct demonstration of synaptic vesicle localization by immunogold or subcellular fractionation\",\n        \"Functional role of the protein on synaptic vesicles unknown\",\n        \"Functional differences among the three splice variants not tested\"\n      ]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"A truncating nonsense mutation in SYNGR1 was linked to schizophrenia in a family study, providing the first genetic evidence that SYNGR1 loss-of-function may contribute to psychiatric disease.\",\n      \"evidence\": \"Sequencing of all SYNGR1 exons and splice junctions in a schizophrenia-affected family, with RT-PCR and Northern blot confirming brain expression of the affected transcript\",\n      \"pmids\": [\"14732601\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No functional assay demonstrating that the truncated protein is non-functional or unstable\",\n        \"Association based on a single family; population-level replication absent\",\n        \"Mechanism linking SYNGR1 loss to schizophrenia pathophysiology not addressed\"\n      ]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"A missense variant (S26G) predicted to abolish a PKC phosphorylation site was identified in schizophrenia patients, raising the possibility that Ser26 phosphorylation regulates SYNGR1 function.\",\n      \"evidence\": \"Resequencing of SYNGR1 exons in schizophrenia cohort with in silico phosphorylation site prediction\",\n      \"pmids\": [\"19641478\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No biochemical confirmation that Ser26 is phosphorylated by PKC in vitro or in vivo\",\n        \"Functional consequence of S26G on protein activity or trafficking not tested\",\n        \"Variant frequency and penetrance in larger cohorts not established\"\n      ]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Systematic proteomics-transcriptomics comparison across auditory brainstem regions demonstrated that SYNGR1 protein is actively transported to axon terminals, resolving how the protein reaches its site of action at the synapse despite somatic mRNA expression.\",\n      \"evidence\": \"DNA microarray transcriptomics and label-free mass spectrometry proteomics across rat auditory brainstem nuclei with correlation analysis\",\n      \"pmids\": [\"30664243\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Active transport mechanism (motor proteins, vesicular carriers) not identified\",\n        \"Direct imaging of SYNGR1 trafficking in live neurons not performed\",\n        \"Whether transport is splice-variant-specific is unknown\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"SYNGR1 was shown to suppress lipid droplet accumulation and actin remodeling in glioblastoma cells by downregulating intracellular FGF1, revealing a non-neuronal signaling axis with epistatic validation.\",\n      \"evidence\": \"Lentiviral overexpression of SYNGR1 and FGF1 in glioblastoma cells with rescue experiments, lipid droplet staining, RNA-seq, Western blot, and intracranial xenograft model with MRI\",\n      \"pmids\": [\"40478501\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Molecular mechanism by which SYNGR1 downregulates FGF1 is unknown\",\n        \"Whether this lipid droplet/cytoskeleton axis operates in neurons is untested\",\n        \"Endogenous SYNGR1 loss-of-function phenotype in glioblastoma not examined\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The precise molecular function of SYNGR1 on synaptic vesicles — whether it acts as a transporter, scaffolding protein, or membrane organizer — remains unknown, and no direct binding partners on the vesicle have been identified.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No interactome or co-immunoprecipitation studies identifying direct binding partners on synaptic vesicles\",\n        \"No knockout or knockdown phenotype characterized in neurons\",\n        \"No structural data from crystallography or cryo-EM\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0031410\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"pathway\": [],\n    \"complexes\": [],\n    \"partners\": [\n      \"FGF1\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}