{"gene":"VAPA","run_date":"2026-06-11T09:02:06","timeline":{"discoveries":[{"year":2002,"finding":"VAPA (VAP-A) physically interacts with oxysterol-binding protein (OSBP) through a region in OSBP spanning amino acids 351-442, and this interaction is required for OSBP targeting to the ER; VAP-A/OSBP complexes at the ER regulate export of membrane cargo (VSVG-GFP) and ceramide from the ER to the Golgi.","method":"Yeast two-hybrid screen, GST pull-down, co-immunoprecipitation, live-cell imaging with ts045-VSVG-GFP cargo trafficking assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal binding confirmed by three orthogonal methods (Y2H, pulldown, co-IP) plus functional trafficking assay in cells; binding domain mapped by truncation analysis","pmids":["12023275"],"is_preprint":false},{"year":2001,"finding":"VAPA is a resident ER/Golgi intermediate compartment protein that binds promiscuously to both v- and t-SNAREs, including VAMP, syntaxin 1A, rbet1, rsec22, alphaSNAP, and NSF; both N- and C-terminal domains of VAPA are required for SNARE binding and VAP dimerization.","method":"Subcellular fractionation, immunofluorescence, in vitro binding/pull-down, domain deletion mutagenesis in COS-7 cells","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct binding assays with domain mapping, single lab, multiple SNARE partners tested","pmids":["11511104"],"is_preprint":false},{"year":2004,"finding":"VAPA (hVAP-33) binds directly to both HCV NS5A and NS5B nonstructural proteins and is required for formation of the HCV RNA replication complex on lipid raft (detergent-resistant membranes); dominant-negative VAPA mutants and siRNA knockdown of VAPA redistributed NS5B from detergent-resistant to detergent-sensitive membranes and reduced HCV RNA and protein levels.","method":"Co-immunoprecipitation, siRNA knockdown, dominant-negative expression, membrane fractionation in HCV replicon hepatocyte cell lines","journal":"Journal of virology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal loss-of-function approaches (dominant-negative + siRNA) with specific biochemical and virological readouts; replicated across approaches in same study","pmids":["15016871"],"is_preprint":false},{"year":2003,"finding":"VAPA interacts with Norwalk virus nonstructural protein p48 and forms a stable complex in mammalian cells; expression of p48 inhibits cell-surface expression of VSV-G glycoprotein, indicating that p48 disrupts intracellular protein trafficking by co-opting VAPA.","method":"Yeast two-hybrid screen, co-immunoprecipitation, fluorescence microscopy, VSV-G surface expression assay in transfected mammalian cells","journal":"Journal of virology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — binding confirmed by Y2H and co-IP, with functional trafficking readout; single lab","pmids":["14557663"],"is_preprint":false},{"year":2008,"finding":"Overexpression of VAPA (but not VAPB) inhibits ER-to-Golgi transport of membrane cargo by reducing segregation into ER vesicles and impeding lateral diffusion of membrane proteins, likely through stable association with microtubules; this inhibitory effect is reversed by expression of an FFAT motif peptide, which also restores in vitro ER vesicle budding and disrupts VAPA-microtubule association.","method":"Live-cell imaging of VSVG-GFP transport, in vitro ER vesicle budding assay, FRAP, microtubule co-sedimentation, FFAT peptide rescue experiments","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — multiple orthogonal methods including in vitro reconstitution (ER vesicle budding) and live-cell assays with specific rescue by FFAT peptide; single lab","pmids":["18713837"],"is_preprint":false},{"year":2009,"finding":"The glycolipid transfer protein (GLTP) contains a FFAT-like motif that mediates direct interaction with VAPA; disruption of specific amino acids in the FFAT-like motif abolishes this interaction.","method":"GST pull-down assay with FFAT-like motif mutagenesis","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pulldown with mutational mapping, single lab, single method type","pmids":["19665998"],"is_preprint":false},{"year":2010,"finding":"VAPA and prestin (the OHC motor protein) interact; VAPA expression correlates with prestin presence in outer hair cells, and co-expression of VAPA with prestin increases prestin abundance at the plasma membrane, suggesting VAPA facilitates prestin transport to the cell surface.","method":"Membrane-based yeast two-hybrid, co-immunoprecipitation, immunofluorescence in prestin-KO vs wild-type OHCs","journal":"Biochimica et biophysica acta","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, binding confirmed by Y2H and co-IP, but trafficking conclusion rests on correlative expression data in KO cells","pmids":["20359505"],"is_preprint":false},{"year":2010,"finding":"Three conserved proline residues in VAPA (compared to two in VAPB) confer resistance to the ALS-associated P56S-equivalent mutation; when VAPA is mutated to match the proline distribution of VAPB-P56S (reducing proline count in the conserved region), VAPA forms ER membrane aggregates indistinguishable from those induced by VAPB-P56S.","method":"Site-directed mutagenesis of VAPA proline residues, fluorescence microscopy of mutant VAPA localization in mammalian cells","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis with clear cellular phenotype, single lab, mechanistic interpretation supported by comparative analysis with yeast Scs2p","pmids":["21144830"],"is_preprint":false},{"year":2011,"finding":"Viperin inhibits HCV replication by binding to VAPA (hVAP-33) through its C-terminus, competitively interfering with the VAPA-NS5A interaction and thereby disrupting the HCV replication complex.","method":"Co-immunoprecipitation, competitive co-immunoprecipitation, laser confocal microscopy, C-terminal viperin mutagenesis, HCV replicon and HCVcc replication assays","journal":"The Journal of general virology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — competitive co-IP demonstrates displacement of NS5A by viperin for VAPA binding; mutagenesis maps domain; single lab","pmids":["21957124"],"is_preprint":false},{"year":2013,"finding":"GPS2 acts as a bridge between HCV NS5A and VAPA: GPS2 directly interacts with NS5A (via Domain I of NS5A and the coiled-coil domain of GPS2), overexpression of GPS2 enhances NS5A-VAPA association, and GPS2 knockdown disrupts the NS5A-VAPA interaction and suppresses HCV RNA replication.","method":"Co-immunoprecipitation in mammalian cells, siRNA knockdown with rescue, domain mutagenesis","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP plus knockdown/rescue plus domain mapping; single lab","pmids":["24223774"],"is_preprint":false},{"year":2015,"finding":"Sterol ligand binding by OSBP, ORP2, and ORP4L regulates the subcellular distribution of their complexes with VAPA; depletion of cholesterol causes juxtanuclear concentration of OSBP-VAPA complexes reversible by LDL addition, while sterol-binding deficient ORP mutants fail to redistribute, demonstrating that VAPA serves as the ER anchor for ORP proteins during lipid-sensing responses.","method":"Bimolecular Fluorescence Complementation (BiFC) to visualize ORP-VAPA complexes in living HuH7 cells, combined with pharmacological sterol manipulation and sterol-binding mutants","journal":"Steroids","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — BiFC with multiple ORPs and sterol-binding mutants; single lab, multiple conditions tested","pmids":["25681634"],"is_preprint":false},{"year":2017,"finding":"Norovirus NS1/2 protein contains a mimic of the host FFAT motif that directly binds to the MSP domain of VAPA; this interaction is required for an early step in norovirus replication (after cytoplasmic RNA entry but before minus-sense RNA synthesis); mutations in the FFAT mimic abolish both VAPA binding and viral replication.","method":"Structural analysis of NS1 FFAT mimic, direct binding assay of NS1/2 to VAPA-MSP domain, VAPA/VAPB-deficient cell replication assays, site-directed mutagenesis of FFAT mimic residues","journal":"mBio","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — structural characterization of FFAT mimic, direct binding with domain mapping, genetic loss-of-function in cells, mutational validation; multiple orthogonal methods in single study","pmids":["28698274"],"is_preprint":false},{"year":2018,"finding":"VAPA and VAPB interact with Kv2.1 and Kv2.2 potassium channels through a noncanonical FFAT-binding domain on VAPA and a phosphorylation-dependent FFAT motif in the Kv2 C-terminus (PRC/clustering motif); this interaction recruits VAPs to ER-PM junctions and is required for Kv2.1 clustering, as VAPA knockout reduces Kv2.1 cluster formation.","method":"Proximity-based biotinylation (BioID), FRET assays, siRNA knockdown, colocalization/redistribution, CD4 chimera domain mapping, affinity immunopurification/mass spectrometry from brain tissue, VAPA knockout in mammalian cells","journal":"Proceedings of the National Academy of Sciences / The Journal of Neuroscience","confidence":"High","confidence_rationale":"Tier 2 / Strong — independently replicated in two papers (PMID 29941597, PMID 30012696) using multiple orthogonal methods including proteomics, FRET, KO, and domain mapping","pmids":["29941597","30012696"],"is_preprint":false},{"year":2018,"finding":"VAPA and VAPB are required for autophagosome biogenesis by tethering the ER to isolation membranes: VAPs directly interact with FIP200 and ULK1 via FFAT motifs, stabilize the ULK1/FIP200 complex at autophagosome formation sites, and interact with WIPI2 to enhance WIPI2/FIP200 ER-IM tethering; VAP depletion reduces ULK1 puncta formation and impairs isolation membrane progression.","method":"Co-immunoprecipitation, siRNA knockdown, fluorescence microscopy of autophagy markers, VAPB P56S mutant analysis","journal":"Current biology : CB","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct interaction with multiple ATG proteins confirmed by co-IP, loss-of-function with specific early autophagy defect, pathogenic mutant recapitulates phenotype; multiple orthogonal approaches","pmids":["29628370"],"is_preprint":false},{"year":2018,"finding":"VAPA and VAPB are required for Aichi virus (AiV) RNA replication and are present at viral RNA replication organelles; various AiV nonstructural proteins (2B, 2BC, 2C, 3A, 3AB) interact with VAP-A/B and with OSBP and SAC1, forming a protein-protein interaction network that recruits the cholesterol transport machinery to replication sites.","method":"siRNA knockdown of VAPA/B with replication assays, co-immunoprecipitation, immunofluorescence colocalization, cholesterol accumulation assay, electron microscopy","journal":"Journal of virology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA knockdown with replication readout plus co-IP for multiple interactions; single lab","pmids":["29367253"],"is_preprint":false},{"year":2020,"finding":"Disruption of the Kv2.1-VAPA interaction by a membrane-permeable peptide (TAT-DP-2) disperses Kv2.1 surface clusters, prevents pro-apoptotic potassium current enhancement after injury, and is neuroprotective both in vitro and in a murine ischemia-reperfusion model, reducing infarct size.","method":"Peptide-based disruption of Kv2.1-VAPA interaction, electrophysiology, in vitro neuronal death assay, murine middle cerebral artery occlusion stroke model","journal":"Science advances","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional disruption of defined protein-protein interaction with multiple readouts in vitro and in vivo; single lab","pmids":["32937450"],"is_preprint":false},{"year":2021,"finding":"VAPA forms a tethering complex with OSBP at membrane contact sites; cryo-tomography reveals that VAPA is highly flexible due to disordered linkers, enabling formation of MCS of variable intermembrane distance, while the OSBP dimer has a T-shaped helical architecture that facilitates lipid transfer domain movement between membranes.","method":"In vitro reconstituted MCS with two membranes, cryo-electron tomography, structural modeling","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution of MCS with cryo-ET structural analysis; single lab but rigorous structural method","pmids":["34103503"],"is_preprint":false},{"year":2021,"finding":"CDIP1 (a pro-apoptotic protein) binds VAPA and VAPB through a FFAT-like motif in CDIP1's C-terminal region; mutations in this FFAT-like motif reduce CDIP1-induced cell death, implicating the VAPA-CDIP1 interaction in apoptosis signaling.","method":"Co-immunoprecipitation of GFP-CDIP1 with VAPA/VAPB, FFAT-like motif mutagenesis, caspase-3/7 cell death assay","journal":"International journal of molecular sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP plus site-directed mutagenesis with functional cell death readout; single lab","pmids":["33503978"],"is_preprint":false},{"year":2021,"finding":"The VAP-A MSP domain binds a diversity of FFAT-like motif peptides with defined sequence requirements; NMR mapping revealed that 6 of 8 tested FFAT-like peptides specifically bind the VAPA MSP domain, and the SARS-CoV-2 RNA-dependent RNA polymerase contains an FFAT-like motif that also specifically binds VAPA-MSP.","method":"Solution NMR chemical shift perturbation mapping of VAP-A MSP domain with synthetic FFAT-like peptides","journal":"FEBS letters","confidence":"High","confidence_rationale":"Tier 1 / Moderate — NMR structural method with multiple peptides tested; direct binding site mapping; single lab","pmids":["34312846"],"is_preprint":false},{"year":2022,"finding":"VAPA regulates biogenesis of a subpopulation of RNA-enriched small extracellular vesicles (EVs) through its interaction with the ceramide transfer protein CERT at ER membrane contact sites; VAPA knockdown reduces EV RNA content and ceramide levels in EVs; VAPA promotes luminal filling of multivesicular bodies and colocalizes with neutral sphingomyelinase 2; VAPA-regulated EVs mediate miR-100 transfer between cells.","method":"siRNA knockdown, lipid analysis (lipidomics), RNA quantification in EVs, live-cell imaging, proximity-ligation assay, in vivo tumor formation assay","journal":"Developmental cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal approaches (KD, lipidomics, imaging, in vivo) in single study linking VAPA-CERT interaction to EV ceramide content and RNA packaging","pmids":["35421371"],"is_preprint":false},{"year":2023,"finding":"VAPA forms a VOR complex with hyperphosphorylated ORP3 and Rab7 at the outer nuclear membrane; HIV-1 endosomes containing endocytosed virus promote nuclear envelope invaginations via this complex; silencing VAPA or ORP3 inhibits nuclear transfer of HIV-1 components and productive infection.","method":"siRNA knockdown, co-immunoprecipitation, fluorescence microscopy, HIV-1 infection assays in HeLa and activated CD4+ T cells","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — complex formation shown by co-IP, functional role shown by knockdown with specific viral replication readout; single lab","pmids":["37563144"],"is_preprint":false},{"year":2023,"finding":"VAPA intrinsically disordered regions (IDRs) are required for its localization to diverse MCS types (ER-mitochondria, ER-Golgi) but do not alter partner preference; removing IDRs restricts VAPA to ER-mitochondria MCS; at ER-mitochondria MCS, VAPA interaction with PTPIP51 and VPS13A promotes lipid transfer and cardiolipin accumulation supporting mitochondria fusion; at ER-Golgi MCS, VAPA interacts with OSBP and CERT for lipid exchange.","method":"IDR deletion mutagenesis, fluorescence microscopy in human cells, lipid analysis (cardiolipin), mitochondria morphology assay, co-immunoprecipitation","journal":"Developmental cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — mutagenesis with multiple functional readouts (lipid transfer, organelle morphology, MCS distribution) across multiple partner interactions; single rigorous study","pmids":["36693319"],"is_preprint":false},{"year":2024,"finding":"VAPA is required for cell motility: VAPA-depleted CaCo2 cells show collective and individual migration defects, disorganized actin cytoskeleton, and altered protrusive activity; VAPA maintains PI(4)P and PI(4,5)P2 levels at the plasma membrane during migration; VAPA MSP domain regulates focal adhesion dynamics, stabilizes and anchors ventral ER-PM contact sites to focal adhesions, and mediates microtubule-dependent focal adhesion disassembly.","method":"siRNA/shRNA knockdown, live-cell migration assays, phosphoinositide biosensors, TIRF microscopy of focal adhesions, immunofluorescence, microtubule depolymerization experiments","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Strong — loss-of-function with multiple specific readouts (migration, PI lipid levels, focal adhesion dynamics, ER-PM contacts), MSP domain identified as functional unit; single lab, multiple orthogonal methods","pmids":["38446032"],"is_preprint":false},{"year":2025,"finding":"VAPA negatively regulates IFN-I (JAK-STAT) signaling during viral infection by facilitating NEDD4 E3 ubiquitin ligase-mediated ubiquitination and proteasomal degradation of JAK1; VAPA promotes the physical interaction between NEDD4 and JAK1; in NEDD4-deficient cells, the pro-viral effect of VAPA is abrogated.","method":"Co-immunoprecipitation of VAPA-NEDD4-JAK1 complex, ubiquitination assay, siRNA knockdown, viral replication assays (BEFV and VSV), NEDD4 knockout cells","journal":"Veterinary microbiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP of ternary complex, ubiquitination assay, and NEDD4 KO rescue; single lab","pmids":["40080976"],"is_preprint":false},{"year":2025,"finding":"VAPA forms a VAPA:ORP1L:RAB7 multi-protein complex at ER-endolysosome membrane contact sites that is required for ER-to-lysosome-associated degradation (ERLAD) of misfolded ATZ polymers; this complex engages calnexin/FAM134B/LC3 in a client-driven manner to facilitate STX17/VAMP8 SNARE-mediated membrane fusion for ATZ delivery to endolysosomes.","method":"Co-immunoprecipitation, proximity ligation, fluorescence microscopy, functional ERLAD assay with ATZ polymers as substrate","journal":"Autophagy reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multi-protein complex identified with functional ERLAD readout; single lab","pmids":["41179805"],"is_preprint":false},{"year":2026,"finding":"VAPA localizes to the inner nuclear membrane (INM) in proximity to nuclear lamins, emerin, LAP2 isoforms, and Nup153; depletion of VAPA reduces nuclear lamin levels and causes aberrant nuclear morphology including membrane invaginations/tunnels and altered histone acetylation levels.","method":"RAPIDS proximity proteomics (rapamycin- and APEX-dependent SILAC), immunofluorescence, VAPA depletion with nuclear morphology and lamin quantification","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — proximity proteomics with validation by knockdown and morphological readouts; single lab, novel INM localization finding","pmids":["41537431"],"is_preprint":false},{"year":2025,"finding":"VAPA mediates lipid exchange between Leishmania amazonensis-containing parasitophorous vacuoles (PVs) and host macrophage ER: VAPA associates with communal PVs after infection; VAPA knockdown prevents parasite replication and PV expansion; VAPA is required for sphingolipid (ceramide) transport to PVs; VAPA normally interacts with CERT and ORP1L, but Leishmania disrupts these interactions; VAPA also mediates retrograde transfer of the Leishmania virulence glycolipid lipophosphoglycan from PVs to the host ER.","method":"siRNA knockdown, fluorescent ceramide transport assay, proximity-ligation assay for VAPA-CERT and VAPA-ORP1L interactions, intracellular parasite growth quantification in bone marrow-derived macrophages","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (KD, lipid transport, PLA, parasite growth), bidirectional lipid transfer functions defined with specific molecular partners identified; single lab","pmids":["40163521"],"is_preprint":false},{"year":2025,"finding":"ORP3 lipid transfer from the plasma membrane to the ER at ER-PM contacts during mitosis depends on VAPA; ORP3 phosphorylation on its VAPA-binding motif strongly recruits ORP3 to the ER for PI4P transfer; VAPA is required for ORP3-mediated regulation of PI4P and PI(4,5)P2 levels at the plasma membrane during cell division.","method":"siRNA knockdown, phosphoinositide biosensors, mutagenesis of ORP3 VAPA-binding motif, mitosis assays","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 3 / Weak — preprint, single lab, functional interaction inferred from knockdown and motif mutagenesis without direct structural or reconstitution evidence","pmids":["bio_10.1101_2025.10.22.684039"],"is_preprint":true}],"current_model":"VAPA is an ER-resident transmembrane protein whose cytoplasmic MSP domain acts as a universal ER scaffold by binding FFAT and FFAT-like motifs in diverse cytoplasmic partners, thereby tethering the ER to multiple organelles (Golgi, mitochondria, plasma membrane, endolysosomes, multivesicular bodies, and pathogen-containing vacuoles) at membrane contact sites to enable non-vesicular lipid transfer, phosphoinositide homeostasis, autophagosome biogenesis, extracellular vesicle RNA packaging, focal adhesion-coupled ER-PM junction maintenance, cell migration, and nuclear architecture; additionally, VAPA facilitates NEDD4-mediated ubiquitin-proteasomal degradation of JAK1 to suppress IFN-I signaling, and is exploited by multiple RNA viruses (HCV, noroviruses, Aichi virus, HIV-1) through direct binding of viral proteins to the VAPA MSP domain."},"narrative":{"mechanistic_narrative":"VAPA is an ER-resident protein whose cytoplasmic MSP domain functions as a universal scaffold that recognizes FFAT and FFAT-like motifs in a broad range of cytoplasmic partners, tethering the ER to other organelles at membrane contact sites to support non-vesicular lipid transfer and phosphoinositide homeostasis [PMID:34312846, PMID:34103503, PMID:36693319]. NMR mapping established that the MSP domain accommodates a diversity of FFAT-like peptides with defined sequence requirements [PMID:34312846], and cryo-tomography of reconstituted contacts showed that flexible disordered linkers allow VAPA to bridge membranes of variable intermembrane distance [PMID:34103503]; its intrinsically disordered regions are required for correct distribution across distinct contact-site types without altering partner preference [PMID:36693319]. Through these interactions VAPA anchors the lipid-transfer proteins OSBP, ORP2/ORP4L and CERT, which sense sterol and deliver lipids at ER–Golgi and ER–mitochondria contacts, contributing to ceramide and cardiolipin handling and to ER-to-Golgi cargo export [PMID:12023275, PMID:25681634, PMID:36693319]. VAPA further organizes ER–plasma membrane junctions: it recruits to Kv2.1/Kv2.2 channels via a phosphorylation-dependent FFAT motif to drive channel clustering [PMID:29941597, PMID:30012696], and it maintains plasma-membrane PI(4)P and PI(4,5)P2 levels while coupling ventral ER–PM contacts to focal adhesions during cell migration [PMID:38446032]. VAPA participates in autophagosome biogenesis by tethering the ER to isolation membranes through FFAT-dependent interactions with FIP200, ULK1 and WIPI2 [PMID:29628370], in ER-to-lysosome-associated degradation of misfolded ATZ via a VAPA:ORP1L:RAB7 complex [PMID:41179805], and in RNA-enriched extracellular vesicle biogenesis through its CERT-dependent control of multivesicular body ceramide and luminal filling [PMID:35421371]. Beyond canonical lipid-transfer roles, VAPA suppresses type I interferon signaling by promoting NEDD4-mediated ubiquitination and proteasomal degradation of JAK1 [PMID:40080976]. VAPA is co-opted by multiple pathogens whose proteins bind the MSP domain through FFAT mimics, including HCV NS5A/NS5B, norovirus NS1/2, Aichi virus nonstructural proteins, and HIV-1, to build replication organelles or remodel host membranes [PMID:15016871, PMID:28698274, PMID:29367253, PMID:37563144].","teleology":[{"year":2002,"claim":"Establishing VAPA's first defined molecular partnership answered whether it acts as an ER anchor for lipid-handling machinery, by showing it binds OSBP and is required for OSBP ER targeting and ER-to-Golgi cargo and ceramide export.","evidence":"Yeast two-hybrid, GST pull-down, co-IP and live-cell VSVG-GFP trafficking in mammalian cells","pmids":["12023275"],"confidence":"High","gaps":["Did not define the FFAT motif consensus on OSBP","Did not establish whether ER anchoring functions at discrete contact sites"]},{"year":2003,"claim":"Identifying VAPA as a target of norovirus p48 introduced the theme that pathogens hijack VAPA to disrupt host trafficking.","evidence":"Yeast two-hybrid, co-IP and VSV-G surface expression assay in transfected cells","pmids":["14557663"],"confidence":"Medium","gaps":["Binding interface on VAPA not mapped","Mechanism of trafficking disruption not resolved"]},{"year":2004,"claim":"Showing VAPA binds HCV NS5A and NS5B and is required for the lipid-raft replication complex established VAPA as an essential host factor for a viral RNA replication organelle.","evidence":"Co-IP, siRNA knockdown, dominant-negative expression and membrane fractionation in HCV replicon hepatocytes","pmids":["15016871"],"confidence":"High","gaps":["Direct binding domain on VAPA not mapped at the time","Did not address how host FFAT partners are displaced"]},{"year":2008,"claim":"Demonstrating that VAPA overexpression inhibits ER-to-Golgi transport, reversible by an FFAT peptide and linked to microtubule association, showed VAPA function is dose-sensitive and FFAT-dependent.","evidence":"Live-cell VSVG-GFP imaging, in vitro ER vesicle budding, FRAP, microtubule co-sedimentation and FFAT peptide rescue","pmids":["18713837"],"confidence":"High","gaps":["Physiological consequence of VAPA-microtubule binding unresolved","Did not identify the relevant endogenous FFAT partners"]},{"year":2010,"claim":"Mutagenesis showing that proline content protects VAPA from the ALS-associated P56S-equivalent aggregation explained why VAPA, unlike VAPB, resists this misfolding fate.","evidence":"Site-directed mutagenesis of VAPA prolines and fluorescence microscopy in mammalian cells","pmids":["21144830"],"confidence":"Medium","gaps":["No disease link for VAPA itself","Aggregation consequences for contact-site function not tested"]},{"year":2015,"claim":"Visualizing ORP-VAPA complexes redistributing with sterol levels established VAPA as the static ER anchor enabling sterol-sensing lipid-transfer proteins to respond to cellular cholesterol.","evidence":"BiFC of ORP-VAPA complexes with pharmacological sterol manipulation and sterol-binding mutants in HuH7 cells","pmids":["25681634"],"confidence":"Medium","gaps":["Did not quantify lipid transfer flux","Did not resolve the contact-site geometry"]},{"year":2017,"claim":"Structural identification of a norovirus FFAT mimic binding the VAPA MSP domain explained mechanistically how viral proteins exploit the same binding pocket as host FFAT partners.","evidence":"Structural analysis of NS1 FFAT mimic, direct MSP-domain binding, VAPA/VAPB-deficient replication assays and mutagenesis","pmids":["28698274"],"confidence":"High","gaps":["Precise replication step requiring VAPA not fully defined","Host partner competition not directly measured"]},{"year":2018,"claim":"Defining VAPA's roles in Kv2 channel clustering, autophagosome biogenesis, and Aichi virus replication organelles broadened VAPA from a lipid-transfer anchor to a general organizer of ER contact sites with diverse partners.","evidence":"BioID/FRET/KO for Kv2 clustering, co-IP and autophagy marker imaging for FIP200/ULK1/WIPI2, and siRNA plus co-IP for AiV nonstructural proteins","pmids":["29941597","30012696","29628370","29367253"],"confidence":"High","gaps":["Stoichiometry and selectivity among competing FFAT partners not resolved","How VAPA prioritizes among simultaneous contact-site demands unknown"]},{"year":2020,"claim":"Showing that a peptide disrupting the Kv2.1-VAPA interaction is neuroprotective in stroke established functional and potentially therapeutic relevance of a specific VAPA contact-site interaction.","evidence":"TAT-DP-2 peptide disruption, electrophysiology, neuronal death assay and murine MCAO stroke model","pmids":["32937450"],"confidence":"Medium","gaps":["Whether other VAPA functions are affected by the peptide not excluded","Long-term consequences not assessed"]},{"year":2021,"claim":"Structural and biophysical characterization of the MSP domain's FFAT-recognition breadth and the flexible VAPA-OSBP tethering architecture explained how one scaffold accommodates many partners and variable contact-site geometries.","evidence":"Solution NMR of MSP with FFAT-like peptides, cryo-ET of reconstituted MCS, plus co-IP/cell-death assays for CDIP1 FFAT-like binding","pmids":["34312846","34103503","33503978"],"confidence":"High","gaps":["In vitro geometry not validated in vivo for all partners","Determinants of partner selectivity at endogenous contacts unresolved"]},{"year":2022,"claim":"Linking VAPA-CERT contacts to multivesicular body ceramide and RNA-enriched extracellular vesicle biogenesis extended VAPA's lipid-transfer role into intercellular RNA communication.","evidence":"siRNA knockdown, lipidomics, EV RNA quantification, PLA, live-cell imaging and in vivo tumor assay","pmids":["35421371"],"confidence":"High","gaps":["Mechanism coupling ceramide transfer to RNA loading not resolved","Selectivity for the EV subpopulation not fully defined"]},{"year":2023,"claim":"Identifying that VAPA's disordered regions govern contact-site distribution, and that VAPA acts at the outer nuclear membrane in HIV-1 nuclear transfer, refined how VAPA partitions among contacts and revealed a role at the nuclear envelope.","evidence":"IDR deletion mutagenesis with lipid/morphology readouts for ER-mitochondria/ER-Golgi, and siRNA/co-IP/HIV-1 infection for the VOR (VAPA-ORP3-RAB7) complex","pmids":["36693319","37563144"],"confidence":"High","gaps":["How IDRs encode contact-site targeting without altering partner choice unresolved","Direct membrane-fusion mechanism in HIV-1 transfer not defined"]},{"year":2024,"claim":"Demonstrating that VAPA maintains plasma-membrane phosphoinositides and couples ER-PM contacts to focal adhesions during migration assigned VAPA a direct role in cytoskeletal and adhesion dynamics.","evidence":"siRNA/shRNA knockdown, live migration assays, PI biosensors, TIRF of focal adhesions and microtubule depolymerization in CaCo2 cells","pmids":["38446032"],"confidence":"High","gaps":["FFAT partner mediating focal-adhesion coupling not identified","Link between PI homeostasis and adhesion disassembly mechanistically incomplete"]},{"year":2025,"claim":"Defining VAPA roles in ERLAD of misfolded ATZ, JAK1 degradation suppressing IFN-I signaling, Leishmania vacuole lipid exchange, and inner nuclear membrane architecture established VAPA as a multifunctional regulator beyond canonical lipid transfer.","evidence":"Co-IP/PLA/ERLAD assay for VAPA:ORP1L:RAB7, ternary complex co-IP and NEDD4-KO ubiquitination for JAK1, siRNA/lipid transport/PLA for Leishmania PVs, and RAPIDS proximity proteomics with morphology readouts for INM","pmids":["41179805","40080976","40163521","41537431"],"confidence":"Medium","gaps":["Mechanism by which VAPA promotes NEDD4-JAK1 association unresolved","Inner nuclear membrane targeting route for an ER protein unclear","Direct versus scaffolding contributions in each role not fully separated"]},{"year":null,"claim":"It remains unresolved how VAPA selects and prioritizes 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STARD3-VAPA interaction enables cholesterol transfer from the ER to endosomes (PubMed:33124732). Via interaction with WDR44 participates in neosynthesized protein export (PubMed:32344433). In addition, recruited to the plasma membrane through OSBPL3 binding (PubMed:25447204). The OSBPL3-VAPA complex stimulates RRAS signaling which in turn attenuates integrin beta-1 (ITGB1) activation at the cell surface (PubMed:25447204). With OSBPL3, may regulate ER morphology (PubMed:16143324). 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NEDHSF","url":"https://www.omim.org/entry/616351"},{"mim_id":"606737","title":"OXYSTEROL-BINDING PROTEIN-LIKE PROTEIN 9; OSBPL9","url":"https://www.omim.org/entry/606737"},{"mim_id":"605704","title":"VAMP-ASSOCIATED PROTEIN B AND C; VAPB","url":"https://www.omim.org/entry/605704"},{"mim_id":"605703","title":"VAMP-ASSOCIATED PROTEIN A; VAPA","url":"https://www.omim.org/entry/605703"},{"mim_id":"604677","title":"CERAMIDE TRANSPORTER 1; CERT1","url":"https://www.omim.org/entry/604677"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Enhanced","locations":[{"location":"Endoplasmic reticulum","reliability":"Enhanced"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in 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\"Yeast two-hybrid screen, GST pull-down, co-immunoprecipitation, live-cell imaging with ts045-VSVG-GFP cargo trafficking assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal binding confirmed by three orthogonal methods (Y2H, pulldown, co-IP) plus functional trafficking assay in cells; binding domain mapped by truncation analysis\",\n      \"pmids\": [\"12023275\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"VAPA is a resident ER/Golgi intermediate compartment protein that binds promiscuously to both v- and t-SNAREs, including VAMP, syntaxin 1A, rbet1, rsec22, alphaSNAP, and NSF; both N- and C-terminal domains of VAPA are required for SNARE binding and VAP dimerization.\",\n      \"method\": \"Subcellular fractionation, immunofluorescence, in vitro binding/pull-down, domain deletion mutagenesis in COS-7 cells\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding assays with domain mapping, single lab, multiple SNARE partners tested\",\n      \"pmids\": [\"11511104\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"VAPA (hVAP-33) binds directly to both HCV NS5A and NS5B nonstructural proteins and is required for formation of the HCV RNA replication complex on lipid raft (detergent-resistant membranes); dominant-negative VAPA mutants and siRNA knockdown of VAPA redistributed NS5B from detergent-resistant to detergent-sensitive membranes and reduced HCV RNA and protein levels.\",\n      \"method\": \"Co-immunoprecipitation, siRNA knockdown, dominant-negative expression, membrane fractionation in HCV replicon hepatocyte cell lines\",\n      \"journal\": \"Journal of virology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal loss-of-function approaches (dominant-negative + siRNA) with specific biochemical and virological readouts; replicated across approaches in same study\",\n      \"pmids\": [\"15016871\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"VAPA interacts with Norwalk virus nonstructural protein p48 and forms a stable complex in mammalian cells; expression of p48 inhibits cell-surface expression of VSV-G glycoprotein, indicating that p48 disrupts intracellular protein trafficking by co-opting VAPA.\",\n      \"method\": \"Yeast two-hybrid screen, co-immunoprecipitation, fluorescence microscopy, VSV-G surface expression assay in transfected mammalian cells\",\n      \"journal\": \"Journal of virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — binding confirmed by Y2H and co-IP, with functional trafficking readout; single lab\",\n      \"pmids\": [\"14557663\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Overexpression of VAPA (but not VAPB) inhibits ER-to-Golgi transport of membrane cargo by reducing segregation into ER vesicles and impeding lateral diffusion of membrane proteins, likely through stable association with microtubules; this inhibitory effect is reversed by expression of an FFAT motif peptide, which also restores in vitro ER vesicle budding and disrupts VAPA-microtubule association.\",\n      \"method\": \"Live-cell imaging of VSVG-GFP transport, in vitro ER vesicle budding assay, FRAP, microtubule co-sedimentation, FFAT peptide rescue experiments\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — multiple orthogonal methods including in vitro reconstitution (ER vesicle budding) and live-cell assays with specific rescue by FFAT peptide; single lab\",\n      \"pmids\": [\"18713837\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The glycolipid transfer protein (GLTP) contains a FFAT-like motif that mediates direct interaction with VAPA; disruption of specific amino acids in the FFAT-like motif abolishes this interaction.\",\n      \"method\": \"GST pull-down assay with FFAT-like motif mutagenesis\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pulldown with mutational mapping, single lab, single method type\",\n      \"pmids\": [\"19665998\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"VAPA and prestin (the OHC motor protein) interact; VAPA expression correlates with prestin presence in outer hair cells, and co-expression of VAPA with prestin increases prestin abundance at the plasma membrane, suggesting VAPA facilitates prestin transport to the cell surface.\",\n      \"method\": \"Membrane-based yeast two-hybrid, co-immunoprecipitation, immunofluorescence in prestin-KO vs wild-type OHCs\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, binding confirmed by Y2H and co-IP, but trafficking conclusion rests on correlative expression data in KO cells\",\n      \"pmids\": [\"20359505\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Three conserved proline residues in VAPA (compared to two in VAPB) confer resistance to the ALS-associated P56S-equivalent mutation; when VAPA is mutated to match the proline distribution of VAPB-P56S (reducing proline count in the conserved region), VAPA forms ER membrane aggregates indistinguishable from those induced by VAPB-P56S.\",\n      \"method\": \"Site-directed mutagenesis of VAPA proline residues, fluorescence microscopy of mutant VAPA localization in mammalian cells\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis with clear cellular phenotype, single lab, mechanistic interpretation supported by comparative analysis with yeast Scs2p\",\n      \"pmids\": [\"21144830\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Viperin inhibits HCV replication by binding to VAPA (hVAP-33) through its C-terminus, competitively interfering with the VAPA-NS5A interaction and thereby disrupting the HCV replication complex.\",\n      \"method\": \"Co-immunoprecipitation, competitive co-immunoprecipitation, laser confocal microscopy, C-terminal viperin mutagenesis, HCV replicon and HCVcc replication assays\",\n      \"journal\": \"The Journal of general virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — competitive co-IP demonstrates displacement of NS5A by viperin for VAPA binding; mutagenesis maps domain; single lab\",\n      \"pmids\": [\"21957124\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"GPS2 acts as a bridge between HCV NS5A and VAPA: GPS2 directly interacts with NS5A (via Domain I of NS5A and the coiled-coil domain of GPS2), overexpression of GPS2 enhances NS5A-VAPA association, and GPS2 knockdown disrupts the NS5A-VAPA interaction and suppresses HCV RNA replication.\",\n      \"method\": \"Co-immunoprecipitation in mammalian cells, siRNA knockdown with rescue, domain mutagenesis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP plus knockdown/rescue plus domain mapping; single lab\",\n      \"pmids\": [\"24223774\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Sterol ligand binding by OSBP, ORP2, and ORP4L regulates the subcellular distribution of their complexes with VAPA; depletion of cholesterol causes juxtanuclear concentration of OSBP-VAPA complexes reversible by LDL addition, while sterol-binding deficient ORP mutants fail to redistribute, demonstrating that VAPA serves as the ER anchor for ORP proteins during lipid-sensing responses.\",\n      \"method\": \"Bimolecular Fluorescence Complementation (BiFC) to visualize ORP-VAPA complexes in living HuH7 cells, combined with pharmacological sterol manipulation and sterol-binding mutants\",\n      \"journal\": \"Steroids\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — BiFC with multiple ORPs and sterol-binding mutants; single lab, multiple conditions tested\",\n      \"pmids\": [\"25681634\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Norovirus NS1/2 protein contains a mimic of the host FFAT motif that directly binds to the MSP domain of VAPA; this interaction is required for an early step in norovirus replication (after cytoplasmic RNA entry but before minus-sense RNA synthesis); mutations in the FFAT mimic abolish both VAPA binding and viral replication.\",\n      \"method\": \"Structural analysis of NS1 FFAT mimic, direct binding assay of NS1/2 to VAPA-MSP domain, VAPA/VAPB-deficient cell replication assays, site-directed mutagenesis of FFAT mimic residues\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — structural characterization of FFAT mimic, direct binding with domain mapping, genetic loss-of-function in cells, mutational validation; multiple orthogonal methods in single study\",\n      \"pmids\": [\"28698274\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"VAPA and VAPB interact with Kv2.1 and Kv2.2 potassium channels through a noncanonical FFAT-binding domain on VAPA and a phosphorylation-dependent FFAT motif in the Kv2 C-terminus (PRC/clustering motif); this interaction recruits VAPs to ER-PM junctions and is required for Kv2.1 clustering, as VAPA knockout reduces Kv2.1 cluster formation.\",\n      \"method\": \"Proximity-based biotinylation (BioID), FRET assays, siRNA knockdown, colocalization/redistribution, CD4 chimera domain mapping, affinity immunopurification/mass spectrometry from brain tissue, VAPA knockout in mammalian cells\",\n      \"journal\": \"Proceedings of the National Academy of Sciences / The Journal of Neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — independently replicated in two papers (PMID 29941597, PMID 30012696) using multiple orthogonal methods including proteomics, FRET, KO, and domain mapping\",\n      \"pmids\": [\"29941597\", \"30012696\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"VAPA and VAPB are required for autophagosome biogenesis by tethering the ER to isolation membranes: VAPs directly interact with FIP200 and ULK1 via FFAT motifs, stabilize the ULK1/FIP200 complex at autophagosome formation sites, and interact with WIPI2 to enhance WIPI2/FIP200 ER-IM tethering; VAP depletion reduces ULK1 puncta formation and impairs isolation membrane progression.\",\n      \"method\": \"Co-immunoprecipitation, siRNA knockdown, fluorescence microscopy of autophagy markers, VAPB P56S mutant analysis\",\n      \"journal\": \"Current biology : CB\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct interaction with multiple ATG proteins confirmed by co-IP, loss-of-function with specific early autophagy defect, pathogenic mutant recapitulates phenotype; multiple orthogonal approaches\",\n      \"pmids\": [\"29628370\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"VAPA and VAPB are required for Aichi virus (AiV) RNA replication and are present at viral RNA replication organelles; various AiV nonstructural proteins (2B, 2BC, 2C, 3A, 3AB) interact with VAP-A/B and with OSBP and SAC1, forming a protein-protein interaction network that recruits the cholesterol transport machinery to replication sites.\",\n      \"method\": \"siRNA knockdown of VAPA/B with replication assays, co-immunoprecipitation, immunofluorescence colocalization, cholesterol accumulation assay, electron microscopy\",\n      \"journal\": \"Journal of virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA knockdown with replication readout plus co-IP for multiple interactions; single lab\",\n      \"pmids\": [\"29367253\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Disruption of the Kv2.1-VAPA interaction by a membrane-permeable peptide (TAT-DP-2) disperses Kv2.1 surface clusters, prevents pro-apoptotic potassium current enhancement after injury, and is neuroprotective both in vitro and in a murine ischemia-reperfusion model, reducing infarct size.\",\n      \"method\": \"Peptide-based disruption of Kv2.1-VAPA interaction, electrophysiology, in vitro neuronal death assay, murine middle cerebral artery occlusion stroke model\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional disruption of defined protein-protein interaction with multiple readouts in vitro and in vivo; single lab\",\n      \"pmids\": [\"32937450\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"VAPA forms a tethering complex with OSBP at membrane contact sites; cryo-tomography reveals that VAPA is highly flexible due to disordered linkers, enabling formation of MCS of variable intermembrane distance, while the OSBP dimer has a T-shaped helical architecture that facilitates lipid transfer domain movement between membranes.\",\n      \"method\": \"In vitro reconstituted MCS with two membranes, cryo-electron tomography, structural modeling\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution of MCS with cryo-ET structural analysis; single lab but rigorous structural method\",\n      \"pmids\": [\"34103503\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"CDIP1 (a pro-apoptotic protein) binds VAPA and VAPB through a FFAT-like motif in CDIP1's C-terminal region; mutations in this FFAT-like motif reduce CDIP1-induced cell death, implicating the VAPA-CDIP1 interaction in apoptosis signaling.\",\n      \"method\": \"Co-immunoprecipitation of GFP-CDIP1 with VAPA/VAPB, FFAT-like motif mutagenesis, caspase-3/7 cell death assay\",\n      \"journal\": \"International journal of molecular sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP plus site-directed mutagenesis with functional cell death readout; single lab\",\n      \"pmids\": [\"33503978\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"The VAP-A MSP domain binds a diversity of FFAT-like motif peptides with defined sequence requirements; NMR mapping revealed that 6 of 8 tested FFAT-like peptides specifically bind the VAPA MSP domain, and the SARS-CoV-2 RNA-dependent RNA polymerase contains an FFAT-like motif that also specifically binds VAPA-MSP.\",\n      \"method\": \"Solution NMR chemical shift perturbation mapping of VAP-A MSP domain with synthetic FFAT-like peptides\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — NMR structural method with multiple peptides tested; direct binding site mapping; single lab\",\n      \"pmids\": [\"34312846\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"VAPA regulates biogenesis of a subpopulation of RNA-enriched small extracellular vesicles (EVs) through its interaction with the ceramide transfer protein CERT at ER membrane contact sites; VAPA knockdown reduces EV RNA content and ceramide levels in EVs; VAPA promotes luminal filling of multivesicular bodies and colocalizes with neutral sphingomyelinase 2; VAPA-regulated EVs mediate miR-100 transfer between cells.\",\n      \"method\": \"siRNA knockdown, lipid analysis (lipidomics), RNA quantification in EVs, live-cell imaging, proximity-ligation assay, in vivo tumor formation assay\",\n      \"journal\": \"Developmental cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal approaches (KD, lipidomics, imaging, in vivo) in single study linking VAPA-CERT interaction to EV ceramide content and RNA packaging\",\n      \"pmids\": [\"35421371\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"VAPA forms a VOR complex with hyperphosphorylated ORP3 and Rab7 at the outer nuclear membrane; HIV-1 endosomes containing endocytosed virus promote nuclear envelope invaginations via this complex; silencing VAPA or ORP3 inhibits nuclear transfer of HIV-1 components and productive infection.\",\n      \"method\": \"siRNA knockdown, co-immunoprecipitation, fluorescence microscopy, HIV-1 infection assays in HeLa and activated CD4+ T cells\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — complex formation shown by co-IP, functional role shown by knockdown with specific viral replication readout; single lab\",\n      \"pmids\": [\"37563144\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"VAPA intrinsically disordered regions (IDRs) are required for its localization to diverse MCS types (ER-mitochondria, ER-Golgi) but do not alter partner preference; removing IDRs restricts VAPA to ER-mitochondria MCS; at ER-mitochondria MCS, VAPA interaction with PTPIP51 and VPS13A promotes lipid transfer and cardiolipin accumulation supporting mitochondria fusion; at ER-Golgi MCS, VAPA interacts with OSBP and CERT for lipid exchange.\",\n      \"method\": \"IDR deletion mutagenesis, fluorescence microscopy in human cells, lipid analysis (cardiolipin), mitochondria morphology assay, co-immunoprecipitation\",\n      \"journal\": \"Developmental cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — mutagenesis with multiple functional readouts (lipid transfer, organelle morphology, MCS distribution) across multiple partner interactions; single rigorous study\",\n      \"pmids\": [\"36693319\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"VAPA is required for cell motility: VAPA-depleted CaCo2 cells show collective and individual migration defects, disorganized actin cytoskeleton, and altered protrusive activity; VAPA maintains PI(4)P and PI(4,5)P2 levels at the plasma membrane during migration; VAPA MSP domain regulates focal adhesion dynamics, stabilizes and anchors ventral ER-PM contact sites to focal adhesions, and mediates microtubule-dependent focal adhesion disassembly.\",\n      \"method\": \"siRNA/shRNA knockdown, live-cell migration assays, phosphoinositide biosensors, TIRF microscopy of focal adhesions, immunofluorescence, microtubule depolymerization experiments\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — loss-of-function with multiple specific readouts (migration, PI lipid levels, focal adhesion dynamics, ER-PM contacts), MSP domain identified as functional unit; single lab, multiple orthogonal methods\",\n      \"pmids\": [\"38446032\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"VAPA negatively regulates IFN-I (JAK-STAT) signaling during viral infection by facilitating NEDD4 E3 ubiquitin ligase-mediated ubiquitination and proteasomal degradation of JAK1; VAPA promotes the physical interaction between NEDD4 and JAK1; in NEDD4-deficient cells, the pro-viral effect of VAPA is abrogated.\",\n      \"method\": \"Co-immunoprecipitation of VAPA-NEDD4-JAK1 complex, ubiquitination assay, siRNA knockdown, viral replication assays (BEFV and VSV), NEDD4 knockout cells\",\n      \"journal\": \"Veterinary microbiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP of ternary complex, ubiquitination assay, and NEDD4 KO rescue; single lab\",\n      \"pmids\": [\"40080976\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"VAPA forms a VAPA:ORP1L:RAB7 multi-protein complex at ER-endolysosome membrane contact sites that is required for ER-to-lysosome-associated degradation (ERLAD) of misfolded ATZ polymers; this complex engages calnexin/FAM134B/LC3 in a client-driven manner to facilitate STX17/VAMP8 SNARE-mediated membrane fusion for ATZ delivery to endolysosomes.\",\n      \"method\": \"Co-immunoprecipitation, proximity ligation, fluorescence microscopy, functional ERLAD assay with ATZ polymers as substrate\",\n      \"journal\": \"Autophagy reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multi-protein complex identified with functional ERLAD readout; single lab\",\n      \"pmids\": [\"41179805\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"VAPA localizes to the inner nuclear membrane (INM) in proximity to nuclear lamins, emerin, LAP2 isoforms, and Nup153; depletion of VAPA reduces nuclear lamin levels and causes aberrant nuclear morphology including membrane invaginations/tunnels and altered histone acetylation levels.\",\n      \"method\": \"RAPIDS proximity proteomics (rapamycin- and APEX-dependent SILAC), immunofluorescence, VAPA depletion with nuclear morphology and lamin quantification\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — proximity proteomics with validation by knockdown and morphological readouts; single lab, novel INM localization finding\",\n      \"pmids\": [\"41537431\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"VAPA mediates lipid exchange between Leishmania amazonensis-containing parasitophorous vacuoles (PVs) and host macrophage ER: VAPA associates with communal PVs after infection; VAPA knockdown prevents parasite replication and PV expansion; VAPA is required for sphingolipid (ceramide) transport to PVs; VAPA normally interacts with CERT and ORP1L, but Leishmania disrupts these interactions; VAPA also mediates retrograde transfer of the Leishmania virulence glycolipid lipophosphoglycan from PVs to the host ER.\",\n      \"method\": \"siRNA knockdown, fluorescent ceramide transport assay, proximity-ligation assay for VAPA-CERT and VAPA-ORP1L interactions, intracellular parasite growth quantification in bone marrow-derived macrophages\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (KD, lipid transport, PLA, parasite growth), bidirectional lipid transfer functions defined with specific molecular partners identified; single lab\",\n      \"pmids\": [\"40163521\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ORP3 lipid transfer from the plasma membrane to the ER at ER-PM contacts during mitosis depends on VAPA; ORP3 phosphorylation on its VAPA-binding motif strongly recruits ORP3 to the ER for PI4P transfer; VAPA is required for ORP3-mediated regulation of PI4P and PI(4,5)P2 levels at the plasma membrane during cell division.\",\n      \"method\": \"siRNA knockdown, phosphoinositide biosensors, mutagenesis of ORP3 VAPA-binding motif, mitosis assays\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — preprint, single lab, functional interaction inferred from knockdown and motif mutagenesis without direct structural or reconstitution evidence\",\n      \"pmids\": [\"bio_10.1101_2025.10.22.684039\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"VAPA is an ER-resident transmembrane protein whose cytoplasmic MSP domain acts as a universal ER scaffold by binding FFAT and FFAT-like motifs in diverse cytoplasmic partners, thereby tethering the ER to multiple organelles (Golgi, mitochondria, plasma membrane, endolysosomes, multivesicular bodies, and pathogen-containing vacuoles) at membrane contact sites to enable non-vesicular lipid transfer, phosphoinositide homeostasis, autophagosome biogenesis, extracellular vesicle RNA packaging, focal adhesion-coupled ER-PM junction maintenance, cell migration, and nuclear architecture; additionally, VAPA facilitates NEDD4-mediated ubiquitin-proteasomal degradation of JAK1 to suppress IFN-I signaling, and is exploited by multiple RNA viruses (HCV, noroviruses, Aichi virus, HIV-1) through direct binding of viral proteins to the VAPA MSP domain.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"VAPA is an ER-resident protein whose cytoplasmic MSP domain functions as a universal scaffold that recognizes FFAT and FFAT-like motifs in a broad range of cytoplasmic partners, tethering the ER to other organelles at membrane contact sites to support non-vesicular lipid transfer and phosphoinositide homeostasis [#18, #16, #21]. NMR mapping established that the MSP domain accommodates a diversity of FFAT-like peptides with defined sequence requirements [#18], and cryo-tomography of reconstituted contacts showed that flexible disordered linkers allow VAPA to bridge membranes of variable intermembrane distance [#16]; its intrinsically disordered regions are required for correct distribution across distinct contact-site types without altering partner preference [#21]. Through these interactions VAPA anchors the lipid-transfer proteins OSBP, ORP2/ORP4L and CERT, which sense sterol and deliver lipids at ER–Golgi and ER–mitochondria contacts, contributing to ceramide and cardiolipin handling and to ER-to-Golgi cargo export [#0, #10, #21]. VAPA further organizes ER–plasma membrane junctions: it recruits to Kv2.1/Kv2.2 channels via a phosphorylation-dependent FFAT motif to drive channel clustering [#12], and it maintains plasma-membrane PI(4)P and PI(4,5)P2 levels while coupling ventral ER–PM contacts to focal adhesions during cell migration [#22]. VAPA participates in autophagosome biogenesis by tethering the ER to isolation membranes through FFAT-dependent interactions with FIP200, ULK1 and WIPI2 [#13], in ER-to-lysosome-associated degradation of misfolded ATZ via a VAPA:ORP1L:RAB7 complex [#24], and in RNA-enriched extracellular vesicle biogenesis through its CERT-dependent control of multivesicular body ceramide and luminal filling [#19]. Beyond canonical lipid-transfer roles, VAPA suppresses type I interferon signaling by promoting NEDD4-mediated ubiquitination and proteasomal degradation of JAK1 [#23]. VAPA is co-opted by multiple pathogens whose proteins bind the MSP domain through FFAT mimics, including HCV NS5A/NS5B, norovirus NS1/2, Aichi virus nonstructural proteins, and HIV-1, to build replication organelles or remodel host membranes [#2, #11, #14, #20].\",\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Establishing VAPA's first defined molecular partnership answered whether it acts as an ER anchor for lipid-handling machinery, by showing it binds OSBP and is required for OSBP ER targeting and ER-to-Golgi cargo and ceramide export.\",\n      \"evidence\": \"Yeast two-hybrid, GST pull-down, co-IP and live-cell VSVG-GFP trafficking in mammalian cells\",\n      \"pmids\": [\"12023275\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the FFAT motif consensus on OSBP\", \"Did not establish whether ER anchoring functions at discrete contact sites\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identifying VAPA as a target of norovirus p48 introduced the theme that pathogens hijack VAPA to disrupt host trafficking.\",\n      \"evidence\": \"Yeast two-hybrid, co-IP and VSV-G surface expression assay in transfected cells\",\n      \"pmids\": [\"14557663\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Binding interface on VAPA not mapped\", \"Mechanism of trafficking disruption not resolved\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Showing VAPA binds HCV NS5A and NS5B and is required for the lipid-raft replication complex established VAPA as an essential host factor for a viral RNA replication organelle.\",\n      \"evidence\": \"Co-IP, siRNA knockdown, dominant-negative expression and membrane fractionation in HCV replicon hepatocytes\",\n      \"pmids\": [\"15016871\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct binding domain on VAPA not mapped at the time\", \"Did not address how host FFAT partners are displaced\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Demonstrating that VAPA overexpression inhibits ER-to-Golgi transport, reversible by an FFAT peptide and linked to microtubule association, showed VAPA function is dose-sensitive and FFAT-dependent.\",\n      \"evidence\": \"Live-cell VSVG-GFP imaging, in vitro ER vesicle budding, FRAP, microtubule co-sedimentation and FFAT peptide rescue\",\n      \"pmids\": [\"18713837\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological consequence of VAPA-microtubule binding unresolved\", \"Did not identify the relevant endogenous FFAT partners\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Mutagenesis showing that proline content protects VAPA from the ALS-associated P56S-equivalent aggregation explained why VAPA, unlike VAPB, resists this misfolding fate.\",\n      \"evidence\": \"Site-directed mutagenesis of VAPA prolines and fluorescence microscopy in mammalian cells\",\n      \"pmids\": [\"21144830\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No disease link for VAPA itself\", \"Aggregation consequences for contact-site function not tested\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Visualizing ORP-VAPA complexes redistributing with sterol levels established VAPA as the static ER anchor enabling sterol-sensing lipid-transfer proteins to respond to cellular cholesterol.\",\n      \"evidence\": \"BiFC of ORP-VAPA complexes with pharmacological sterol manipulation and sterol-binding mutants in HuH7 cells\",\n      \"pmids\": [\"25681634\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not quantify lipid transfer flux\", \"Did not resolve the contact-site geometry\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Structural identification of a norovirus FFAT mimic binding the VAPA MSP domain explained mechanistically how viral proteins exploit the same binding pocket as host FFAT partners.\",\n      \"evidence\": \"Structural analysis of NS1 FFAT mimic, direct MSP-domain binding, VAPA/VAPB-deficient replication assays and mutagenesis\",\n      \"pmids\": [\"28698274\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Precise replication step requiring VAPA not fully defined\", \"Host partner competition not directly measured\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defining VAPA's roles in Kv2 channel clustering, autophagosome biogenesis, and Aichi virus replication organelles broadened VAPA from a lipid-transfer anchor to a general organizer of ER contact sites with diverse partners.\",\n      \"evidence\": \"BioID/FRET/KO for Kv2 clustering, co-IP and autophagy marker imaging for FIP200/ULK1/WIPI2, and siRNA plus co-IP for AiV nonstructural proteins\",\n      \"pmids\": [\"29941597\", \"30012696\", \"29628370\", \"29367253\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and selectivity among competing FFAT partners not resolved\", \"How VAPA prioritizes among simultaneous contact-site demands unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Showing that a peptide disrupting the Kv2.1-VAPA interaction is neuroprotective in stroke established functional and potentially therapeutic relevance of a specific VAPA contact-site interaction.\",\n      \"evidence\": \"TAT-DP-2 peptide disruption, electrophysiology, neuronal death assay and murine MCAO stroke model\",\n      \"pmids\": [\"32937450\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether other VAPA functions are affected by the peptide not excluded\", \"Long-term consequences not assessed\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Structural and biophysical characterization of the MSP domain's FFAT-recognition breadth and the flexible VAPA-OSBP tethering architecture explained how one scaffold accommodates many partners and variable contact-site geometries.\",\n      \"evidence\": \"Solution NMR of MSP with FFAT-like peptides, cryo-ET of reconstituted MCS, plus co-IP/cell-death assays for CDIP1 FFAT-like binding\",\n      \"pmids\": [\"34312846\", \"34103503\", \"33503978\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vitro geometry not validated in vivo for all partners\", \"Determinants of partner selectivity at endogenous contacts unresolved\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Linking VAPA-CERT contacts to multivesicular body ceramide and RNA-enriched extracellular vesicle biogenesis extended VAPA's lipid-transfer role into intercellular RNA communication.\",\n      \"evidence\": \"siRNA knockdown, lipidomics, EV RNA quantification, PLA, live-cell imaging and in vivo tumor assay\",\n      \"pmids\": [\"35421371\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism coupling ceramide transfer to RNA loading not resolved\", \"Selectivity for the EV subpopulation not fully defined\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identifying that VAPA's disordered regions govern contact-site distribution, and that VAPA acts at the outer nuclear membrane in HIV-1 nuclear transfer, refined how VAPA partitions among contacts and revealed a role at the nuclear envelope.\",\n      \"evidence\": \"IDR deletion mutagenesis with lipid/morphology readouts for ER-mitochondria/ER-Golgi, and siRNA/co-IP/HIV-1 infection for the VOR (VAPA-ORP3-RAB7) complex\",\n      \"pmids\": [\"36693319\", \"37563144\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How IDRs encode contact-site targeting without altering partner choice unresolved\", \"Direct membrane-fusion mechanism in HIV-1 transfer not defined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrating that VAPA maintains plasma-membrane phosphoinositides and couples ER-PM contacts to focal adhesions during migration assigned VAPA a direct role in cytoskeletal and adhesion dynamics.\",\n      \"evidence\": \"siRNA/shRNA knockdown, live migration assays, PI biosensors, TIRF of focal adhesions and microtubule depolymerization in CaCo2 cells\",\n      \"pmids\": [\"38446032\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"FFAT partner mediating focal-adhesion coupling not identified\", \"Link between PI homeostasis and adhesion disassembly mechanistically incomplete\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Defining VAPA roles in ERLAD of misfolded ATZ, JAK1 degradation suppressing IFN-I signaling, Leishmania vacuole lipid exchange, and inner nuclear membrane architecture established VAPA as a multifunctional regulator beyond canonical lipid transfer.\",\n      \"evidence\": \"Co-IP/PLA/ERLAD assay for VAPA:ORP1L:RAB7, ternary complex co-IP and NEDD4-KO ubiquitination for JAK1, siRNA/lipid transport/PLA for Leishmania PVs, and RAPIDS proximity proteomics with morphology readouts for INM\",\n      \"pmids\": [\"41179805\", \"40080976\", \"40163521\", \"41537431\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which VAPA promotes NEDD4-JAK1 association unresolved\", \"Inner nuclear membrane targeting route for an ER protein unclear\", \"Direct versus scaffolding contributions in each role not fully separated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how VAPA selects and prioritizes among its many competing FFAT/FFAT-like partners to deploy the correct contact-site function in a given cellular context.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No quantitative model of partner competition at endogenous VAPA\", \"Regulation of VAPA partitioning between organelle contacts not defined\", \"Phosphoregulation of partner FFAT motifs not systematically mapped\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 12, 16, 18, 21]},\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [19, 21, 26]},\n      {\"term_id\": \"GO:0001618\", \"supporting_discovery_ids\": [2, 11, 14, 20]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0, 16, 21, 22]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [12, 22, 27]},\n      {\"term_id\": \"GO:0005635\", \"supporting_discovery_ids\": [20, 25]},\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [21]},\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [0, 21]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 10, 19, 21]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [13, 24]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [2, 11, 14, 20]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [23]},\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [0, 4]}\n    ],\n    \"complexes\": [\n      \"VAPA-OSBP MCS tethering complex\",\n      \"VAPA:ORP3:RAB7 (VOR) complex\",\n      \"VAPA:ORP1L:RAB7 ERLAD complex\"\n    ],\n    \"partners\": [\n      \"OSBP\",\n      \"CERT\",\n      \"ORP1L\",\n      \"ORP3\",\n      \"KCNB1\",\n      \"FIP200\",\n      \"ULK1\",\n      \"PTPIP51\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}