{"gene":"SLC5A7","run_date":"2026-06-10T07:46:34","timeline":{"discoveries":[{"year":2006,"finding":"hCHT (SLC5A7) undergoes rapid endocytosis from the plasma membrane via clathrin-coated pits, dependent on a dileucine-like motif in the carboxyl-terminal region; the intracellular pool resides in endosomal compartments and synaptic vesicles and constitutes a reserve pool for cholinergic neurotransmission.","method":"Review synthesizing prior cell-biological experiments including subcellular fractionation, immunolocalization, and mutagenesis of dileucine motif","journal":"Journal of neurochemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple independent labs, reciprocal localization and trafficking data with mutagenesis of endocytosis motif","pmids":["16524384"],"is_preprint":false},{"year":2006,"finding":"hCHT (SLC5A7) expressed in Xenopus oocytes mediates Na+- and Cl−-dependent choline transport and choline-induced current; Cl− plays a regulatory (not co-transported) role; external protons reduce hCHT current, transport, and HC-3 binding with pKa ~7.4, indicating proton titration of residues supporting choline binding; HC-3 reveals a constitutive depolarizing leak current; a trafficking mutant L530A/V531A significantly enhances surface expression and current.","method":"Voltage-clamp electrophysiology and radiolabeled choline uptake in Xenopus oocytes expressing hCHT; ion substitution; pharmacological inhibition with HC-3; pH titration experiments","journal":"The Journal of neuroscience","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution in Xenopus oocyte expression system with voltage clamp, transport assays, mutagenesis, and multiple ion substitution experiments in a single rigorous study","pmids":["17005849"],"is_preprint":false},{"year":2004,"finding":"Par-4 (prostate apoptosis response-4) physically interacts with CHT1 (SLC5A7) through its C-terminal half and negatively regulates CHT1-mediated choline uptake by reducing CHT1 incorporation into the plasma membrane, without altering CHT1 affinity for choline or HC-3; Par-4·CHT1 complex formation is required for this inhibitory effect.","method":"Co-immunoprecipitation, mapping of Par-4 interaction domain, transfection of IMR-32 neural cells, kinetic choline uptake assays, cell-surface biotinylation","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP with domain mapping, cell-surface biotinylation, and kinetic assays; single lab but multiple orthogonal methods","pmids":["15090548"],"is_preprint":false},{"year":2012,"finding":"The ubiquitin E3 ligase Nedd4-2 interacts with CHT1 (SLC5A7) in HEK293 cells, ubiquitinates it, and reduces cell-surface CHT1 levels by ~40%; siRNA knockdown of endogenous Nedd4-2 enhances CHT1-mediated choline uptake, indicating that Nedd4-2-mediated ubiquitination downregulates surface expression of CHT1.","method":"Co-immunoprecipitation in HEK293 cells, siRNA knockdown of Nedd4-2, choline uptake assay, surface expression quantification","journal":"Biomedical research (Tokyo, Japan)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus siRNA rescue of uptake activity; single lab with two orthogonal methods","pmids":["22361880"],"is_preprint":false},{"year":2007,"finding":"Acute exposure to the peroxynitrite generator SIN-1 inhibits CHT (SLC5A7) choline uptake by reducing Vmax without altering Km, accelerates internalization of CHT from the plasma membrane, and decreases cell-surface CHT protein (assessed by HC-3 binding and biotinylation), without affecting CHT recycling back to the surface.","method":"Radiolabeled choline uptake kinetics, cell-surface biotinylation, HC-3 binding, and internalization rate assays in cells stably expressing FLAG-tagged rat CHT","journal":"Molecular pharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal biochemical assays (uptake kinetics, biotinylation, HC-3 binding) in a single-lab study with dose-response and time-course controls","pmids":["17971421"],"is_preprint":false},{"year":2015,"finding":"Insulin signaling via the PI3-kinase/PKB(Akt) pathway acutely increases cell-surface levels of CHT (SLC5A7) in depolarized cells and transiently promotes choline uptake; chronic insulin exposure causes insulin resistance, abolishes acute insulin-stimulated phospho-Akt, and reduces choline uptake; PI3-kinase inhibition decreases phospho-Akt, lowers choline uptake, and paradoxically increases CHT surface levels by slowing internalization.","method":"Radiolabeled choline uptake assays, Western blotting for phospho-Akt, total internal reflection fluorescence (TIRF) live-cell imaging of CHT trafficking in differentiated SH-SY5Y cells stably expressing CHT, PI3K inhibitor treatments","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — TIRF live imaging plus biochemical uptake and phosphorylation assays; single lab with multiple orthogonal methods","pmids":["26161852"],"is_preprint":false},{"year":2017,"finding":"Cell-derived β-amyloid peptides (Aβ) decrease CHT (SLC5A7) choline uptake activity and reduce cell-surface CHT protein levels; Aβ promotes CHT trafficking to lysosomes for degradation; blocking lysosomal degradation with bafilomycin A1 partially rescues surface CHT but not CHT activity; an anti-Aβ antibody directed at the N-terminal amino acids 1–16 of Aβ (but not a mid-region antibody) attenuates both the Aβ-mediated decrease in CHT activity and trafficking.","method":"Choline uptake assays, cell-surface biotinylation, subcellular fractionation/immunofluorescence for early endosomes and lysosomes, bafilomycin A1 treatment, neutralizing antibody experiments in SH-SY5Y neural cells","journal":"Frontiers in molecular neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (uptake, biotinylation, subcellular localization, pharmacological and antibody rescue) in a single-lab study","pmids":["29163036"],"is_preprint":false},{"year":2006,"finding":"CHT1 (SLC5A7)-mediated choline uptake is significantly reduced in primary cortical neurons from presenilin-1 M146V knock-in mice; kinetic analysis shows reduced HC-3 binding affinity without a change in plasma membrane CHT1 protein levels, indicating the PS-1 mutation impairs CHT1 ligand-binding affinity rather than surface expression.","method":"Radiolabeled choline uptake kinetics, HC-3 binding assays, cell-surface biotinylation in primary cortical neurons from PS-1 M146V knock-in mice","journal":"Brain research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple biochemical assays (uptake kinetics, HC-3 binding, biotinylation) in genetically defined knock-in neurons; single lab","pmids":["17196556"],"is_preprint":false},{"year":2016,"finding":"CXCL12 upregulates CHT1 (SLC5A7) mRNA and protein expression via the Akt signaling pathway; pharmacological inhibition of Akt (GSK690693) abolishes CXCL12-stimulated CHT1 expression and associated increases in choline acetyltransferase activity and ACh production in PC12 cells and primary rat neuronal cultures.","method":"Western blotting for p-Akt and CHT1 protein, RT-PCR for CHT1 mRNA, ELISA for ACh, choline acetyltransferase activity assay; pharmacological Akt inhibition","journal":"Cellular physiology and biochemistry","confidence":"Low","confidence_rationale":"Tier 3 / Weak — pharmacological pathway inhibition with gene expression readouts; single lab, no direct CHT1 activity measurement","pmids":["27941337"],"is_preprint":false},{"year":2026,"finding":"Cryo-EM structures of a bacterial Na+-dependent choline transporter (sfCHT) with high sequence identity to SLC5A7 (CHT1) reveal a LeuT-fold architecture with Na+ coordination geometry conserved with CHT1; captured in an inward-facing conformation with choline at a site near the cytoplasmic side; computational analysis and mutagenesis of conserved residues in sfCHT and CHT1 variants identify local conformational rearrangements along a defined cytosolic pathway, establishing an evolutionarily conserved translocation mechanism.","method":"Cryo-EM structure determination of Na+- and choline-bound sfCHT; computational analysis; transport assays of sfCHT and CHT1 site-directed variants","journal":"Science advances","confidence":"High","confidence_rationale":"Tier 1 / Strong — cryo-EM structure with mutagenesis and transport assays providing orthogonal mechanistic validation in a single rigorous study","pmids":["42213839"],"is_preprint":false},{"year":2003,"finding":"CHT1 (SLC5A7) protein is localized to the apical membrane of ciliated tracheal epithelial cells (non-neuronal), and is co-localized with choline acetyltransferase at the same site, supporting a role for CHT1-mediated choline uptake in non-neuronal ACh synthesis in airway epithelium.","method":"RT-PCR, in situ hybridization, immunohistochemistry with confocal laser scanning and electron microscopy using affinity-purified antisera","journal":"American journal of respiratory cell and molecular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct subcellular localization by electron microscopy and confocal imaging with functional inference from co-localization; single lab","pmids":["12654636"],"is_preprint":false},{"year":2003,"finding":"CHT1 (SLC5A7) is expressed and functionally active in non-neuronal vascular cells (endothelial cells, smooth muscle cells, fibroblasts) of rat and human arteries; high-affinity [3H]-choline uptake in rat aortic segments is hemicholinium-3-sensitive and Na+-dependent, mirroring neuronal high-affinity choline uptake.","method":"RT-PCR, Western blot (single 50 kDa band), immunohistochemistry, microimager autoradiography with [3H]-choline and HC-3 competition in aortic segments and primary vascular cell cultures","journal":"The journal of histochemistry and cytochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional choline uptake assay plus protein expression in primary cells; single lab with multiple orthogonal methods","pmids":["14623932"],"is_preprint":false},{"year":2014,"finding":"CHT1 (SLC5A7) is an integral membrane protein with 13 transmembrane segments belonging to the Na+/glucose co-transporter family (SLC5); a single nucleotide polymorphism (SNP) causing an Ile-to-Val substitution in the third transmembrane segment reduces choline uptake activity to 50–60% of wild-type, with higher prevalence in Asian populations.","method":"Functional characterization of SNP variant by choline uptake assay; hydropathy analysis for topology; sequence homology analysis","journal":"Journal of biochemistry","confidence":"Medium","confidence_rationale":"Tier 1–2 / Moderate — direct functional assay of SNP variant with defined activity measurement; review article but cites original experimental data from the author's lab","pmids":["25073461"],"is_preprint":false}],"current_model":"SLC5A7 (CHT1/hCHT) is a 13-transmembrane Na+-dependent high-affinity choline transporter at cholinergic presynaptic terminals that mediates the rate-limiting choline reuptake step for acetylcholine synthesis; its transport activity and surface availability are dynamically regulated by clathrin-mediated endocytosis via a C-terminal dileucine motif, recycling from synaptic vesicle and endosomal pools, Nedd4-2-mediated ubiquitination, PI3K/Akt-dependent trafficking, and interactions with Par-4; external protons inactivate the transporter (pKa ~7.4) to prevent futile choline loss from acidic synaptic vesicles; cryo-EM structures of a bacterial ortholog reveal a conserved LeuT-fold inward-facing translocation mechanism that is recapitulated by CHT1 mutagenesis."},"narrative":{"mechanistic_narrative":"SLC5A7 (CHT1/hCHT) is a Na+-dependent high-affinity choline transporter that mediates the choline reuptake step supplying acetylcholine synthesis [PMID:17005849, PMID:25073461]. Expressed in Xenopus oocytes it carries out Na+- and Cl−-dependent choline transport and a hemicholinium-3 (HC-3)-sensitive choline-induced current, with Cl− acting in a regulatory rather than co-transported role; external protons titrate residues supporting choline binding to reduce transport and HC-3 binding with a pKa near 7.4 [PMID:17005849]. The protein adopts a 13-transmembrane topology in the SLC5 (Na+/glucose co-transporter) family [PMID:25073461], and cryo-EM of the closely related bacterial ortholog sfCHT establishes a conserved LeuT-fold inward-facing translocation mechanism with Na+ coordination and a cytosolic choline-release pathway recapitulated by CHT1 mutagenesis [PMID:42213839]. Transporter availability is set largely by regulated surface trafficking: CHT1 undergoes rapid clathrin-mediated endocytosis dependent on a C-terminal dileucine-like motif, with an intracellular endosomal and synaptic-vesicle reserve pool, such that disrupting the motif (L530A/V531A) enhances surface expression and current [PMID:16524384, PMID:17005849]. Surface levels are downregulated by Par-4 binding, which reduces membrane incorporation without changing choline affinity [PMID:15090548], and by Nedd4-2-mediated ubiquitination [PMID:22361880], while insulin acting through PI3-kinase/Akt acutely increases surface CHT and choline uptake [PMID:26161852]. Beyond cholinergic neurons, CHT1 is also expressed and functionally active in non-neuronal tissues including ciliated tracheal epithelium and vascular cells [PMID:12654636, PMID:14623932]. A coding SNP causing an Ile-to-Val substitution in the third transmembrane segment reduces uptake activity to 50–60% of wild-type [PMID:25073461].","teleology":[{"year":2003,"claim":"Established that CHT1 function is not restricted to neurons by demonstrating active, HC-3-sensitive high-affinity choline uptake in non-neuronal epithelial and vascular cells, broadening its physiological scope to peripheral ACh synthesis.","evidence":"RT-PCR, immunohistochemistry, electron microscopy, and [3H]-choline uptake in tracheal epithelium and aortic segments/vascular cells","pmids":["12654636","14623932"],"confidence":"Medium","gaps":["Functional consequence of non-neuronal ACh synthesis not defined","Trafficking regulation in these cells not addressed"]},{"year":2004,"claim":"Identified Par-4 as a physical partner that negatively regulates CHT1 by limiting its plasma-membrane incorporation, providing an early mechanism for setting surface transporter density.","evidence":"Reciprocal Co-IP with domain mapping, cell-surface biotinylation, and kinetic choline uptake in transfected IMR-32 neural cells","pmids":["15090548"],"confidence":"Medium","gaps":["Single lab","Physiological context of Par-4 regulation in vivo unclear","Mechanism by which Par-4 blocks membrane incorporation undefined"]},{"year":2006,"claim":"Defined the core transport biophysics and the endocytic basis for a reserve pool, showing Na+/Cl−-dependent choline transport, proton inactivation, and a dileucine-dependent clathrin endocytosis pathway with a surface-enhancing trafficking mutant.","evidence":"Voltage-clamp electrophysiology, choline uptake and pH titration in Xenopus oocytes; subcellular fractionation, immunolocalization, and dileucine-motif mutagenesis (review synthesis)","pmids":["17005849","16524384"],"confidence":"High","gaps":["Stoichiometry of Na+ coupling not fully resolved","Endogenous trigger for endocytic cycling not defined"]},{"year":2006,"claim":"Linked CHT1 dysfunction to a presenilin-1 mutation, showing the M146V allele impairs CHT1 ligand-binding affinity rather than its surface expression.","evidence":"Choline uptake kinetics, HC-3 binding, and biotinylation in primary cortical neurons from PS-1 M146V knock-in mice","pmids":["17196556"],"confidence":"Medium","gaps":["Molecular mechanism by which PS-1 alters CHT1 affinity unknown","Not extended to human disease tissue"]},{"year":2007,"claim":"Showed nitrosative/oxidative stress (peroxynitrite) suppresses choline uptake by accelerating CHT1 internalization, identifying redox stress as an acute regulator of surface transporter.","evidence":"Choline uptake kinetics, biotinylation, HC-3 binding, and internalization assays in cells expressing FLAG-tagged rat CHT","pmids":["17971421"],"confidence":"Medium","gaps":["Molecular target of peroxynitrite on CHT not identified","Single lab"]},{"year":2012,"claim":"Identified Nedd4-2 as an E3 ligase that ubiquitinates CHT1 and downregulates its surface level, placing CHT1 turnover under ubiquitin control.","evidence":"Reciprocal Co-IP, Nedd4-2 siRNA knockdown, and choline uptake/surface quantification in HEK293 cells","pmids":["22361880"],"confidence":"Medium","gaps":["Ubiquitination site on CHT1 not mapped","Single lab, heterologous cells"]},{"year":2014,"claim":"Defined CHT1 topology as a 13-TM SLC5-family transporter and showed a third-TM Ile-to-Val SNP reduces uptake to 50–60%, linking sequence variation to transport capacity.","evidence":"Functional uptake assay of SNP variant, hydropathy/topology analysis, sequence homology","pmids":["25073461"],"confidence":"Medium","gaps":["Population-level phenotypic consequence of SNP not established","Structural basis of the SNP effect not resolved at the time"]},{"year":2015,"claim":"Established insulin–PI3K/Akt signaling as an acute regulator of CHT1 surface trafficking and demonstrated that chronic insulin (insulin resistance) blunts this control.","evidence":"Choline uptake, phospho-Akt Western blots, PI3K inhibition, and TIRF live-cell imaging of CHT trafficking in differentiated SH-SY5Y cells","pmids":["26161852"],"confidence":"Medium","gaps":["Direct molecular link between Akt and CHT trafficking machinery undefined","Single lab"]},{"year":2017,"claim":"Connected β-amyloid to cholinergic deficit by showing Aβ reduces surface CHT1 and routes it to lysosomal degradation, with N-terminal Aβ antibody rescue.","evidence":"Uptake assays, biotinylation, endosome/lysosome localization, bafilomycin A1 and neutralizing antibody experiments in SH-SY5Y cells","pmids":["29163036"],"confidence":"Medium","gaps":["Receptor mediating Aβ effect on CHT1 not identified","Bafilomycin rescued surface but not activity, leaving an additional inhibitory mechanism unexplained"]},{"year":2016,"claim":"Suggested transcriptional/translational upregulation of CHT1 by CXCL12 via Akt, coupling chemokine signaling to cholinergic capacity.","evidence":"Western blot, RT-PCR, ACh ELISA, ChAT activity, and pharmacological Akt inhibition in PC12 cells and primary rat neurons","pmids":["27941337"],"confidence":"Low","gaps":["Pharmacological inhibition only, no direct CHT1 activity measurement","Single lab","Direct transcriptional mechanism not established"]},{"year":2026,"claim":"Resolved the structural mechanism of choline translocation by cryo-EM of a bacterial ortholog, establishing a conserved LeuT-fold inward-facing pathway validated by CHT1 mutagenesis.","evidence":"Cryo-EM of Na+/choline-bound sfCHT, computational analysis, and transport assays of sfCHT and CHT1 site-directed variants","pmids":["42213839"],"confidence":"High","gaps":["No experimental structure of human CHT1 itself","Outward-facing and intermediate states not captured"]},{"year":null,"claim":"How the multiple surface-regulatory inputs (Par-4, Nedd4-2 ubiquitination, PI3K/Akt, redox stress, Aβ) are integrated at the endocytic/recycling machinery to set CHT1 density at active terminals remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking signaling inputs to the dileucine/clathrin endocytic apparatus","No human CHT1 structure to map regulatory residues","In vivo relevance of individual regulators largely untested"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005215","term_label":"transporter activity","supporting_discovery_ids":[1,9,11,12]},{"term_id":"GO:0140104","term_label":"molecular carrier activity","supporting_discovery_ids":[1,9]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,1,4,10]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[0,6]},{"term_id":"GO:0031410","term_label":"cytoplasmic vesicle","supporting_discovery_ids":[0]},{"term_id":"GO:0005764","term_label":"lysosome","supporting_discovery_ids":[6]}],"pathway":[{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[0,1]},{"term_id":"R-HSA-382551","term_label":"Transport of small molecules","supporting_discovery_ids":[1,9,11,12]},{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[0,3,5,6]}],"complexes":[],"partners":["PAWR","NEDD4L"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9GZV3","full_name":"High affinity choline transporter 1","aliases":["Hemicholinium-3-sensitive choline transporter","CHT","Solute carrier family 5 member 7"],"length_aa":580,"mass_kda":63.2,"function":"High-affinity Na(+)-coupled choline transmembrane symporter (PubMed:11027560, PubMed:11068039, PubMed:12237312, PubMed:12969261, PubMed:17005849, PubMed:23132865, PubMed:23141292, PubMed:27569547). Functions as an electrogenic, voltage-dependent transporter with variable charge/choline stoichiometry (PubMed:17005849). Choline uptake and choline-induced current is also Cl(-)-dependent where Cl(-) is likely a regulatory ion rather than cotransported ion (PubMed:11068039, PubMed:12237312, PubMed:17005849). Plays a critical role in acetylcholine (ACh) synthesis by taking up the substrate choline from the synaptic cleft into the presynaptic nerve terminals after neurotransmitter release (PubMed:27569547). SLC5A7/CHT1-mediated choline high-affinity transport in cholinergic neurons is the rate-limiting step for production of ACh, thereby facilitating communication by subsequent action potentials (PubMed:11027560). Localized predominantly in presynaptic terminal intracellular organelles, and translocated to the plasma membrane in active form in response to neuronal activity (PubMed:12969261, PubMed:15953352)","subcellular_location":"Presynaptic cell membrane; Cell projection, axon; Early endosome membrane; Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane","url":"https://www.uniprot.org/uniprotkb/Q9GZV3/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/SLC5A7","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/SLC5A7","total_profiled":1310},"omim":[{"mim_id":"617143","title":"MYASTHENIC SYNDROME, CONGENITAL, 20, PRESYNAPTIC; CMS20","url":"https://www.omim.org/entry/617143"},{"mim_id":"608761","title":"SOLUTE CARRIER FAMILY 5 (CHOLINE TRANSPORTER), MEMBER 7; SLC5A7","url":"https://www.omim.org/entry/608761"},{"mim_id":"601462","title":"MYASTHENIC SYNDROME, CONGENITAL, 1A, SLOW-CHANNEL; CMS1A","url":"https://www.omim.org/entry/601462"},{"mim_id":"182960","title":"NEURONOPATHY, DISTAL HEREDITARY MOTOR, AUTOSOMAL DOMINANT 1; HMND1","url":"https://www.omim.org/entry/182960"},{"mim_id":"158580","title":"NEURONOPATHY, DISTAL HEREDITARY MOTOR, AUTOSOMAL DOMINANT 7; HMND7","url":"https://www.omim.org/entry/158580"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Cell Junctions","reliability":"Approved"},{"location":"Intermediate filaments","reliability":"Approved"},{"location":"Nuclear bodies","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"brain","ntpm":2.2},{"tissue":"intestine","ntpm":2.6}],"url":"https://www.proteinatlas.org/search/SLC5A7"},"hgnc":{"alias_symbol":["hCHT","CHT1","ChT"],"prev_symbol":[]},"alphafold":{"accession":"Q9GZV3","domains":[{"cath_id":"1.20.1730.10","chopping":"6-405","consensus_level":"high","plddt":89.691,"start":6,"end":405},{"cath_id":"-","chopping":"428-531","consensus_level":"medium","plddt":83.392,"start":428,"end":531}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9GZV3","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9GZV3-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9GZV3-F1-predicted_aligned_error_v6.png","plddt_mean":84.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=SLC5A7","jax_strain_url":"https://www.jax.org/strain/search?query=SLC5A7"},"sequence":{"accession":"Q9GZV3","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9GZV3.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9GZV3/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9GZV3"}},"corpus_meta":[{"pmid":"16524384","id":"PMC_16524384","title":"The \"ins\" and \"outs\" of the high-affinity choline transporter CHT1.","date":"2006","source":"Journal of neurochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16524384","citation_count":76,"is_preprint":false},{"pmid":"12744513","id":"PMC_12744513","title":"Flagellin from an incompatible strain of Acidovorax avenae mediates H2O2 generation accompanying hypersensitive cell death and expression of PAL, Cht-1, and PBZ1, but not of Lox in rice.","date":"2003","source":"Molecular plant-microbe interactions : MPMI","url":"https://pubmed.ncbi.nlm.nih.gov/12744513","citation_count":52,"is_preprint":false},{"pmid":"17005849","id":"PMC_17005849","title":"Na+, Cl-, and pH dependence of the human choline transporter (hCHT) in Xenopus oocytes: the proton inactivation hypothesis of hCHT in synaptic vesicles.","date":"2006","source":"The Journal of neuroscience : the official journal of the Society for 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\"discoveries\": [\n    {\n      \"year\": 2006,\n      \"finding\": \"hCHT (SLC5A7) undergoes rapid endocytosis from the plasma membrane via clathrin-coated pits, dependent on a dileucine-like motif in the carboxyl-terminal region; the intracellular pool resides in endosomal compartments and synaptic vesicles and constitutes a reserve pool for cholinergic neurotransmission.\",\n      \"method\": \"Review synthesizing prior cell-biological experiments including subcellular fractionation, immunolocalization, and mutagenesis of dileucine motif\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple independent labs, reciprocal localization and trafficking data with mutagenesis of endocytosis motif\",\n      \"pmids\": [\"16524384\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"hCHT (SLC5A7) expressed in Xenopus oocytes mediates Na+- and Cl−-dependent choline transport and choline-induced current; Cl− plays a regulatory (not co-transported) role; external protons reduce hCHT current, transport, and HC-3 binding with pKa ~7.4, indicating proton titration of residues supporting choline binding; HC-3 reveals a constitutive depolarizing leak current; a trafficking mutant L530A/V531A significantly enhances surface expression and current.\",\n      \"method\": \"Voltage-clamp electrophysiology and radiolabeled choline uptake in Xenopus oocytes expressing hCHT; ion substitution; pharmacological inhibition with HC-3; pH titration experiments\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution in Xenopus oocyte expression system with voltage clamp, transport assays, mutagenesis, and multiple ion substitution experiments in a single rigorous study\",\n      \"pmids\": [\"17005849\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Par-4 (prostate apoptosis response-4) physically interacts with CHT1 (SLC5A7) through its C-terminal half and negatively regulates CHT1-mediated choline uptake by reducing CHT1 incorporation into the plasma membrane, without altering CHT1 affinity for choline or HC-3; Par-4·CHT1 complex formation is required for this inhibitory effect.\",\n      \"method\": \"Co-immunoprecipitation, mapping of Par-4 interaction domain, transfection of IMR-32 neural cells, kinetic choline uptake assays, cell-surface biotinylation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP with domain mapping, cell-surface biotinylation, and kinetic assays; single lab but multiple orthogonal methods\",\n      \"pmids\": [\"15090548\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"The ubiquitin E3 ligase Nedd4-2 interacts with CHT1 (SLC5A7) in HEK293 cells, ubiquitinates it, and reduces cell-surface CHT1 levels by ~40%; siRNA knockdown of endogenous Nedd4-2 enhances CHT1-mediated choline uptake, indicating that Nedd4-2-mediated ubiquitination downregulates surface expression of CHT1.\",\n      \"method\": \"Co-immunoprecipitation in HEK293 cells, siRNA knockdown of Nedd4-2, choline uptake assay, surface expression quantification\",\n      \"journal\": \"Biomedical research (Tokyo, Japan)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus siRNA rescue of uptake activity; single lab with two orthogonal methods\",\n      \"pmids\": [\"22361880\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Acute exposure to the peroxynitrite generator SIN-1 inhibits CHT (SLC5A7) choline uptake by reducing Vmax without altering Km, accelerates internalization of CHT from the plasma membrane, and decreases cell-surface CHT protein (assessed by HC-3 binding and biotinylation), without affecting CHT recycling back to the surface.\",\n      \"method\": \"Radiolabeled choline uptake kinetics, cell-surface biotinylation, HC-3 binding, and internalization rate assays in cells stably expressing FLAG-tagged rat CHT\",\n      \"journal\": \"Molecular pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal biochemical assays (uptake kinetics, biotinylation, HC-3 binding) in a single-lab study with dose-response and time-course controls\",\n      \"pmids\": [\"17971421\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Insulin signaling via the PI3-kinase/PKB(Akt) pathway acutely increases cell-surface levels of CHT (SLC5A7) in depolarized cells and transiently promotes choline uptake; chronic insulin exposure causes insulin resistance, abolishes acute insulin-stimulated phospho-Akt, and reduces choline uptake; PI3-kinase inhibition decreases phospho-Akt, lowers choline uptake, and paradoxically increases CHT surface levels by slowing internalization.\",\n      \"method\": \"Radiolabeled choline uptake assays, Western blotting for phospho-Akt, total internal reflection fluorescence (TIRF) live-cell imaging of CHT trafficking in differentiated SH-SY5Y cells stably expressing CHT, PI3K inhibitor treatments\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — TIRF live imaging plus biochemical uptake and phosphorylation assays; single lab with multiple orthogonal methods\",\n      \"pmids\": [\"26161852\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Cell-derived β-amyloid peptides (Aβ) decrease CHT (SLC5A7) choline uptake activity and reduce cell-surface CHT protein levels; Aβ promotes CHT trafficking to lysosomes for degradation; blocking lysosomal degradation with bafilomycin A1 partially rescues surface CHT but not CHT activity; an anti-Aβ antibody directed at the N-terminal amino acids 1–16 of Aβ (but not a mid-region antibody) attenuates both the Aβ-mediated decrease in CHT activity and trafficking.\",\n      \"method\": \"Choline uptake assays, cell-surface biotinylation, subcellular fractionation/immunofluorescence for early endosomes and lysosomes, bafilomycin A1 treatment, neutralizing antibody experiments in SH-SY5Y neural cells\",\n      \"journal\": \"Frontiers in molecular neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (uptake, biotinylation, subcellular localization, pharmacological and antibody rescue) in a single-lab study\",\n      \"pmids\": [\"29163036\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"CHT1 (SLC5A7)-mediated choline uptake is significantly reduced in primary cortical neurons from presenilin-1 M146V knock-in mice; kinetic analysis shows reduced HC-3 binding affinity without a change in plasma membrane CHT1 protein levels, indicating the PS-1 mutation impairs CHT1 ligand-binding affinity rather than surface expression.\",\n      \"method\": \"Radiolabeled choline uptake kinetics, HC-3 binding assays, cell-surface biotinylation in primary cortical neurons from PS-1 M146V knock-in mice\",\n      \"journal\": \"Brain research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple biochemical assays (uptake kinetics, HC-3 binding, biotinylation) in genetically defined knock-in neurons; single lab\",\n      \"pmids\": [\"17196556\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CXCL12 upregulates CHT1 (SLC5A7) mRNA and protein expression via the Akt signaling pathway; pharmacological inhibition of Akt (GSK690693) abolishes CXCL12-stimulated CHT1 expression and associated increases in choline acetyltransferase activity and ACh production in PC12 cells and primary rat neuronal cultures.\",\n      \"method\": \"Western blotting for p-Akt and CHT1 protein, RT-PCR for CHT1 mRNA, ELISA for ACh, choline acetyltransferase activity assay; pharmacological Akt inhibition\",\n      \"journal\": \"Cellular physiology and biochemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — pharmacological pathway inhibition with gene expression readouts; single lab, no direct CHT1 activity measurement\",\n      \"pmids\": [\"27941337\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"Cryo-EM structures of a bacterial Na+-dependent choline transporter (sfCHT) with high sequence identity to SLC5A7 (CHT1) reveal a LeuT-fold architecture with Na+ coordination geometry conserved with CHT1; captured in an inward-facing conformation with choline at a site near the cytoplasmic side; computational analysis and mutagenesis of conserved residues in sfCHT and CHT1 variants identify local conformational rearrangements along a defined cytosolic pathway, establishing an evolutionarily conserved translocation mechanism.\",\n      \"method\": \"Cryo-EM structure determination of Na+- and choline-bound sfCHT; computational analysis; transport assays of sfCHT and CHT1 site-directed variants\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — cryo-EM structure with mutagenesis and transport assays providing orthogonal mechanistic validation in a single rigorous study\",\n      \"pmids\": [\"42213839\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"CHT1 (SLC5A7) protein is localized to the apical membrane of ciliated tracheal epithelial cells (non-neuronal), and is co-localized with choline acetyltransferase at the same site, supporting a role for CHT1-mediated choline uptake in non-neuronal ACh synthesis in airway epithelium.\",\n      \"method\": \"RT-PCR, in situ hybridization, immunohistochemistry with confocal laser scanning and electron microscopy using affinity-purified antisera\",\n      \"journal\": \"American journal of respiratory cell and molecular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct subcellular localization by electron microscopy and confocal imaging with functional inference from co-localization; single lab\",\n      \"pmids\": [\"12654636\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"CHT1 (SLC5A7) is expressed and functionally active in non-neuronal vascular cells (endothelial cells, smooth muscle cells, fibroblasts) of rat and human arteries; high-affinity [3H]-choline uptake in rat aortic segments is hemicholinium-3-sensitive and Na+-dependent, mirroring neuronal high-affinity choline uptake.\",\n      \"method\": \"RT-PCR, Western blot (single 50 kDa band), immunohistochemistry, microimager autoradiography with [3H]-choline and HC-3 competition in aortic segments and primary vascular cell cultures\",\n      \"journal\": \"The journal of histochemistry and cytochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional choline uptake assay plus protein expression in primary cells; single lab with multiple orthogonal methods\",\n      \"pmids\": [\"14623932\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"CHT1 (SLC5A7) is an integral membrane protein with 13 transmembrane segments belonging to the Na+/glucose co-transporter family (SLC5); a single nucleotide polymorphism (SNP) causing an Ile-to-Val substitution in the third transmembrane segment reduces choline uptake activity to 50–60% of wild-type, with higher prevalence in Asian populations.\",\n      \"method\": \"Functional characterization of SNP variant by choline uptake assay; hydropathy analysis for topology; sequence homology analysis\",\n      \"journal\": \"Journal of biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — direct functional assay of SNP variant with defined activity measurement; review article but cites original experimental data from the author's lab\",\n      \"pmids\": [\"25073461\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"SLC5A7 (CHT1/hCHT) is a 13-transmembrane Na+-dependent high-affinity choline transporter at cholinergic presynaptic terminals that mediates the rate-limiting choline reuptake step for acetylcholine synthesis; its transport activity and surface availability are dynamically regulated by clathrin-mediated endocytosis via a C-terminal dileucine motif, recycling from synaptic vesicle and endosomal pools, Nedd4-2-mediated ubiquitination, PI3K/Akt-dependent trafficking, and interactions with Par-4; external protons inactivate the transporter (pKa ~7.4) to prevent futile choline loss from acidic synaptic vesicles; cryo-EM structures of a bacterial ortholog reveal a conserved LeuT-fold inward-facing translocation mechanism that is recapitulated by CHT1 mutagenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"SLC5A7 (CHT1/hCHT) is a Na+-dependent high-affinity choline transporter that mediates the choline reuptake step supplying acetylcholine synthesis [#1, #12]. Expressed in Xenopus oocytes it carries out Na+- and Cl−-dependent choline transport and a hemicholinium-3 (HC-3)-sensitive choline-induced current, with Cl− acting in a regulatory rather than co-transported role; external protons titrate residues supporting choline binding to reduce transport and HC-3 binding with a pKa near 7.4 [#1]. The protein adopts a 13-transmembrane topology in the SLC5 (Na+/glucose co-transporter) family [#12], and cryo-EM of the closely related bacterial ortholog sfCHT establishes a conserved LeuT-fold inward-facing translocation mechanism with Na+ coordination and a cytosolic choline-release pathway recapitulated by CHT1 mutagenesis [#9]. Transporter availability is set largely by regulated surface trafficking: CHT1 undergoes rapid clathrin-mediated endocytosis dependent on a C-terminal dileucine-like motif, with an intracellular endosomal and synaptic-vesicle reserve pool, such that disrupting the motif (L530A/V531A) enhances surface expression and current [#0, #1]. Surface levels are downregulated by Par-4 binding, which reduces membrane incorporation without changing choline affinity [#2], and by Nedd4-2-mediated ubiquitination [#3], while insulin acting through PI3-kinase/Akt acutely increases surface CHT and choline uptake [#5]. Beyond cholinergic neurons, CHT1 is also expressed and functionally active in non-neuronal tissues including ciliated tracheal epithelium and vascular cells [#10, #11]. A coding SNP causing an Ile-to-Val substitution in the third transmembrane segment reduces uptake activity to 50–60% of wild-type [#12].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Established that CHT1 function is not restricted to neurons by demonstrating active, HC-3-sensitive high-affinity choline uptake in non-neuronal epithelial and vascular cells, broadening its physiological scope to peripheral ACh synthesis.\",\n      \"evidence\": \"RT-PCR, immunohistochemistry, electron microscopy, and [3H]-choline uptake in tracheal epithelium and aortic segments/vascular cells\",\n      \"pmids\": [\"12654636\", \"14623932\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of non-neuronal ACh synthesis not defined\", \"Trafficking regulation in these cells not addressed\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Identified Par-4 as a physical partner that negatively regulates CHT1 by limiting its plasma-membrane incorporation, providing an early mechanism for setting surface transporter density.\",\n      \"evidence\": \"Reciprocal Co-IP with domain mapping, cell-surface biotinylation, and kinetic choline uptake in transfected IMR-32 neural cells\",\n      \"pmids\": [\"15090548\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Physiological context of Par-4 regulation in vivo unclear\", \"Mechanism by which Par-4 blocks membrane incorporation undefined\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Defined the core transport biophysics and the endocytic basis for a reserve pool, showing Na+/Cl−-dependent choline transport, proton inactivation, and a dileucine-dependent clathrin endocytosis pathway with a surface-enhancing trafficking mutant.\",\n      \"evidence\": \"Voltage-clamp electrophysiology, choline uptake and pH titration in Xenopus oocytes; subcellular fractionation, immunolocalization, and dileucine-motif mutagenesis (review synthesis)\",\n      \"pmids\": [\"17005849\", \"16524384\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry of Na+ coupling not fully resolved\", \"Endogenous trigger for endocytic cycling not defined\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Linked CHT1 dysfunction to a presenilin-1 mutation, showing the M146V allele impairs CHT1 ligand-binding affinity rather than its surface expression.\",\n      \"evidence\": \"Choline uptake kinetics, HC-3 binding, and biotinylation in primary cortical neurons from PS-1 M146V knock-in mice\",\n      \"pmids\": [\"17196556\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism by which PS-1 alters CHT1 affinity unknown\", \"Not extended to human disease tissue\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Showed nitrosative/oxidative stress (peroxynitrite) suppresses choline uptake by accelerating CHT1 internalization, identifying redox stress as an acute regulator of surface transporter.\",\n      \"evidence\": \"Choline uptake kinetics, biotinylation, HC-3 binding, and internalization assays in cells expressing FLAG-tagged rat CHT\",\n      \"pmids\": [\"17971421\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular target of peroxynitrite on CHT not identified\", \"Single lab\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified Nedd4-2 as an E3 ligase that ubiquitinates CHT1 and downregulates its surface level, placing CHT1 turnover under ubiquitin control.\",\n      \"evidence\": \"Reciprocal Co-IP, Nedd4-2 siRNA knockdown, and choline uptake/surface quantification in HEK293 cells\",\n      \"pmids\": [\"22361880\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Ubiquitination site on CHT1 not mapped\", \"Single lab, heterologous cells\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Defined CHT1 topology as a 13-TM SLC5-family transporter and showed a third-TM Ile-to-Val SNP reduces uptake to 50–60%, linking sequence variation to transport capacity.\",\n      \"evidence\": \"Functional uptake assay of SNP variant, hydropathy/topology analysis, sequence homology\",\n      \"pmids\": [\"25073461\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Population-level phenotypic consequence of SNP not established\", \"Structural basis of the SNP effect not resolved at the time\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Established insulin–PI3K/Akt signaling as an acute regulator of CHT1 surface trafficking and demonstrated that chronic insulin (insulin resistance) blunts this control.\",\n      \"evidence\": \"Choline uptake, phospho-Akt Western blots, PI3K inhibition, and TIRF live-cell imaging of CHT trafficking in differentiated SH-SY5Y cells\",\n      \"pmids\": [\"26161852\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct molecular link between Akt and CHT trafficking machinery undefined\", \"Single lab\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Connected β-amyloid to cholinergic deficit by showing Aβ reduces surface CHT1 and routes it to lysosomal degradation, with N-terminal Aβ antibody rescue.\",\n      \"evidence\": \"Uptake assays, biotinylation, endosome/lysosome localization, bafilomycin A1 and neutralizing antibody experiments in SH-SY5Y cells\",\n      \"pmids\": [\"29163036\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Receptor mediating Aβ effect on CHT1 not identified\", \"Bafilomycin rescued surface but not activity, leaving an additional inhibitory mechanism unexplained\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Suggested transcriptional/translational upregulation of CHT1 by CXCL12 via Akt, coupling chemokine signaling to cholinergic capacity.\",\n      \"evidence\": \"Western blot, RT-PCR, ACh ELISA, ChAT activity, and pharmacological Akt inhibition in PC12 cells and primary rat neurons\",\n      \"pmids\": [\"27941337\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Pharmacological inhibition only, no direct CHT1 activity measurement\", \"Single lab\", \"Direct transcriptional mechanism not established\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Resolved the structural mechanism of choline translocation by cryo-EM of a bacterial ortholog, establishing a conserved LeuT-fold inward-facing pathway validated by CHT1 mutagenesis.\",\n      \"evidence\": \"Cryo-EM of Na+/choline-bound sfCHT, computational analysis, and transport assays of sfCHT and CHT1 site-directed variants\",\n      \"pmids\": [\"42213839\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No experimental structure of human CHT1 itself\", \"Outward-facing and intermediate states not captured\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the multiple surface-regulatory inputs (Par-4, Nedd4-2 ubiquitination, PI3K/Akt, redox stress, Aβ) are integrated at the endocytic/recycling machinery to set CHT1 density at active terminals remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking signaling inputs to the dileucine/clathrin endocytic apparatus\", \"No human CHT1 structure to map regulatory residues\", \"In vivo relevance of individual regulators largely untested\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005215\", \"supporting_discovery_ids\": [1, 9, 11, 12]},\n      {\"term_id\": \"GO:0140104\", \"supporting_discovery_ids\": [1, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 1, 4, 10]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [0, 6]},\n      {\"term_id\": \"GO:0031410\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005764\", \"supporting_discovery_ids\": [6]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"R-HSA-382551\", \"supporting_discovery_ids\": [1, 9, 11, 12]},\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [0, 3, 5, 6]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"PAWR\", \"NEDD4L\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}