{"gene":"TMEM163","run_date":"2026-06-10T10:51:55","timeline":{"discoveries":[{"year":2014,"finding":"TMEM163 physically interacts with TRPML1 ion channel, and this interaction depends on TMEM163's N-terminus (deletion of part of the N-terminus disrupts it). TRPML1 co-expression reduces plasma membrane levels of TMEM163, while a PM-retained TRPML1 mutant retains TMEM163 at the PM. TMEM163 knockdown or co-knockdown with TRPML1 causes significantly elevated intracellular zinc levels, demonstrating a cooperative role in cellular zinc homeostasis.","method":"Yeast two-hybrid, co-immunoprecipitation, mass spectrometry, confocal microscopy, N-terminal deletion mutagenesis, fluorescent zinc assays, siRNA knockdown in HEK-293 cells","journal":"Traffic (Copenhagen, Denmark)","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (Y2H, Co-IP, MS, confocal, mutagenesis, functional zinc assays) in a single study with clear mechanistic readouts","pmids":["25130899"],"is_preprint":false},{"year":2007,"finding":"TMEM163 (SV31) is a synaptic vesicle membrane protein of 31 kDa with six putative transmembrane helices, localized to synaptic vesicles in select brain regions including glutamatergic and GABAergic nerve terminals, as demonstrated by subcellular fractionation, immunocytochemistry of brain sections, and immunoelectron microscopy.","method":"Subcellular fractionation, heterologous expression, immunocytochemistry of brain sections, immunoelectron microscopy","journal":"Journal of neurochemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal localization methods (fractionation, IEM, ICC) consistently demonstrating synaptic vesicle localization","pmids":["17623043"],"is_preprint":false},{"year":2011,"finding":"TMEM163 (SV31) binds divalent cations Zn2+ and Ni2+ and to a minor extent Cu2+, but not Fe2+, Co2+, Mn2+, or Ca2+. In PC12 cells, SV31-RFP partially co-fractionates with synaptic-like vesicle markers and early endosome marker Rab5, and localizes near the plasma membrane in a compartment positive for SNAP-25 and syntaxin1A.","method":"Recombinant protein metal-binding assays, heterologous transfection of PC12 cells, fluorescent zinc indicator (FluoZin-3), sucrose density gradient fractionation, immunocytochemistry","journal":"Journal of neurochemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct metal-binding assay combined with orthogonal localization methods (fractionation + ICC) in cellular context","pmids":["21668449"],"is_preprint":false},{"year":2016,"finding":"TMEM163 (SV31) assembles into dimers when inserted into nanodisc bilayers, with dimerization increasing Zn2+ binding. Site-directed mutagenesis of two conserved aspartate residues markedly reduces Zn2+ binding but does not affect dimerization. Chemical modification of histidine residues also reduces Zn2+ binding. Reconstituted in proteoliposomes, SV31 mediates proton-dependent Zn2+ transport with a Km of 44.3 μM, requiring external Zn2+ and internal acidic pH.","method":"Cell-free protein synthesis, nanodisc reconstitution, site-directed mutagenesis, native mass spectrometry, proteoliposome transport assay with FluoZin-1","journal":"Journal of neurochemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution in proteoliposomes plus mutagenesis and structural characterization, multiple orthogonal methods establishing transport mechanism","pmids":["27917477"],"is_preprint":false},{"year":2019,"finding":"Human TMEM163 functions as a zinc efflux transporter in cells. Cells stably or transiently expressing TMEM163 show significantly reduced intracellular zinc levels as measured by two fluorescent zinc dyes and radionuclide 65Zn. Alanine substitution of two conserved aspartate residues (D124A/D128A) or the E286K variant significantly reduces zinc efflux, establishing these residues as important for transport function. Phylogenetic analysis places TMEM163 within the CDF/SLC30 zinc efflux family.","method":"Stable and transient expression in human cell lines, fluorescent zinc dyes (two independent), 65Zn radionuclide assay, TPEN chelation control, site-directed mutagenesis, sequence alignment and phylogenetics","journal":"Archives of biochemistry and biophysics","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct zinc efflux demonstrated by three independent assays (two fluorescent dyes + radionuclide), functional mutagenesis identifying key residues","pmids":["31697912"],"is_preprint":false},{"year":2019,"finding":"Knockdown of endogenous Tmem163 in MIN6 pancreatic beta cells results in increased intracellular zinc, increased total insulin content, but compromised glucose-stimulated insulin secretion and enhanced cellular glucose uptake, placing TMEM163 in the pathway of zinc-regulated insulin storage and secretion.","method":"siRNA knockdown in MIN6 cells, intracellular zinc measurement, insulin content and secretion assays, glucose uptake assay","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean knockdown with multiple functional readouts in a single lab, but no reconstitution or mutagenesis to establish direct mechanism","pmids":["31813547"],"is_preprint":false},{"year":2020,"finding":"TMEM163 specifically modulates the channel properties and pharmacology of ATP-gated P2X receptors (P2XRs) in vivo. Genome-wide ORF screening identified TMEM163 as a P2XR modulator; it is required for full function of neuronal P2XR and pain-related ATP-evoked behavior.","method":"Genome-wide ORF functional screen, electrophysiology (implied by channel property assessment), in vivo behavioral assays for pain","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genome-wide functional screen plus in vivo behavioral validation, but mechanistic details of how TMEM163 modulates P2XR are not fully detailed in the abstract","pmids":["32492420"],"is_preprint":false},{"year":2022,"finding":"Heterozygous missense variants in TMEM163 residing in the conserved cytoplasmic domain cause hypomyelinating leukodystrophy. Functional in vitro analysis shows significant impairment of zinc efflux by mutant proteins. Expression of mutant TMEM163 in an oligodendroglial cell line reduces mRNA expression of key myelin genes, decreases branching, and increases cell death, establishing a role for TMEM163-mediated zinc efflux in oligodendrocyte development.","method":"Whole exome sequencing, in vitro zinc efflux assays with disease variants, oligodendroglial cell line expression, qPCR for myelin genes, cell morphology and viability assays","journal":"Brain : a journal of neurology","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct functional assay of disease variants plus oligodendrocyte cellular phenotype, replicated across four unrelated families with two orthogonal functional readouts","pmids":["35953447"],"is_preprint":false},{"year":2022,"finding":"Two de novo TMEM163 variants (L76R, L76P) cause hypomyelinating leukodystrophy. Functional zinc flux assays show L76R attenuates and L76P enhances zinc efflux. In zebrafish, knockdown of tmem163a/b causes myelin deficit, locomotor disability, and oligodendrocyte/neuron loss; wild-type human TMEM163 rescues the morphant phenotype, while L76R and L76P mutants fail to rescue or worsen it. TMEM163 localizes to the plasma membrane, lysosomes, early endosomes, and other vesicular compartments.","method":"Functional zinc flux assays (HeLa stable expression), zebrafish morphant model (siRNA knockdown of tmem163a/b), mRNA rescue experiments, locomotor assays, immunostaining for myelin and oligodendrocyte markers","journal":"Cells","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vitro functional assay plus in vivo zebrafish rescue with multiple orthogonal phenotypic readouts across two studies showing convergent findings","pmids":["35455965"],"is_preprint":false},{"year":2022,"finding":"TMEM163 forms homodimers and heterodimerizes with ZNT1, ZNT2, and ZNT3, but not with ZNT4 (negative control for heterodimerization was not excluded). TMEM163 and ZNT proteins partially co-localize in cells. TMEM163/ZNT heterodimers exhibit similar zinc efflux function as TMEM163 homodimers. Plasma membrane localization of TMEM163 is not markedly altered by ZNT co-expression.","method":"Co-immunoprecipitation with unique peptide tags, Western blot, confocal microscopy co-localization, cell surface biotinylation, functional zinc flux assays (FluoZin-3, Newport Green)","journal":"Biochemistry and biophysics reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP with multiple ZNT partners plus functional and localization validation in a single lab","pmids":["36204728"],"is_preprint":false},{"year":2024,"finding":"TMEM163 is expressed in a subset of dorsal root ganglion neurons enriched with vesicular Zn2+. These neurons form direct synapses with spinal NPY+ inhibitory interneurons and modulate their activity. In aged mice, TMEM163 expression and vesicular Zn2+ concentration are elevated in central terminals of TMEM163+ afferents; excessive vesicular Zn2+ release dampens NPY+ interneuron activity, causing disinhibition of itch circuits and chronic itch. Zinc chelation in the spinal dorsal horn relieves itch in aged mice.","method":"Immunofluorescence, fluorescent zinc imaging, conditional knockout/neuron-specific analysis, electrophysiology of spinal interneurons, zinc chelation pharmacology in vivo (aged mice)","journal":"PLoS biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo functional circuit experiments with pharmacological rescue, but abstract does not detail full mechanistic rigor (single lab, limited by abstract detail)","pmids":["39602426"],"is_preprint":false},{"year":2025,"finding":"ZnT3 and TMEM163 physically interact (co-immunoprecipitation confirmed) and cooperatively regulate zinc homeostasis in hippocampal neurons. Under oxygen-glucose deprivation (OGD), both proteins are upregulated and translocate from the cell membrane to the cytoplasm. Overexpression of TMEM163 exacerbates extracellular zinc efflux and neuronal apoptosis under OGD; silencing attenuates zinc overload and neurodegeneration. TMEM163 thus contributes to ischemia-induced neuronal injury via zinc dyshomeostasis.","method":"siRNA silencing and plasmid overexpression in rat primary hippocampal neurons, OGD model, MTT assay, TUNEL staining, FluoZin-3 zinc measurement, ELISA, co-immunoprecipitation, cell surface biotinylation, RT-qPCR, Western blot","journal":"Frontiers in bioscience (Landmark edition)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP plus gain-of-function and loss-of-function with multiple phenotypic readouts in primary neurons, single lab","pmids":["41504061"],"is_preprint":false},{"year":2026,"finding":"A conserved N-terminal acidic dileucine motif (LEDRGL69L70) in TMEM163 is essential for interaction with BLOC-1 and AP-3 complexes but dispensable for binding AP-1, AP-2, and BLOC-2. Mutation of this motif causes TMEM163 accumulation at the plasma membrane. Loss of BLOC-1 or AP-3 enhances TMEM163 binding to the other complex and results in differential abnormal endo-lysosomal localization, indicating competitive binding and sequential sorting of TMEM163 by AP-3 and BLOC-1 to platelet dense granules. TMEM163 is degraded via the proteasome in cells lacking AP-1, AP-2, AP-3, BLOC-1, or BLOC-2.","method":"Co-immunoprecipitation, mutagenesis of dileucine motif, confocal microscopy subcellular localization, MEG-01 cell lines deficient in endosomal trafficking complexes, proteasome inhibition assays, cell surface biotinylation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — site-directed mutagenesis of sorting motif combined with reciprocal Co-IP across multiple complex members and subcellular localization readouts, establishing a defined trafficking mechanism","pmids":["41985787"],"is_preprint":false}],"current_model":"TMEM163 is a zinc efflux transporter (designated ZNT11/SLC30A11) belonging to the CDF/SLC30 family that forms homodimers and heterodimers with ZNT1–3; it localizes to the plasma membrane, lysosomes, early endosomes, and synaptic vesicles via a dileucine sorting motif that engages AP-3 and BLOC-1 for trafficking to lysosome-related organelles; two conserved aspartate residues (D124/D128) and E286 are critical for its proton-dependent zinc efflux activity; it interacts with TRPML1 to cooperatively regulate lysosomal zinc homeostasis, modulates ATP-gated P2X receptor pharmacology, mediates vesicular zinc release in dorsal root ganglion neurons to regulate itch circuits, and its loss-of-function variants impair oligodendrocyte zinc homeostasis causing hypomyelinating leukodystrophy."},"narrative":{"mechanistic_narrative":"TMEM163 (SV31, ZNT11/SLC30A11) is a proton-coupled zinc efflux transporter of the CDF/SLC30 family that controls cellular and vesicular zinc homeostasis [PMID:31697912]. Reconstitution in proteoliposomes establishes that it mediates Zn2+ transport that depends on external zinc and an internal acidic pH, with transport activity assembling on the homodimer; two conserved aspartate residues and histidine residues are required for zinc binding [PMID:27917477], and alanine substitution of these aspartates (D124A/D128A) or the E286K variant abolishes efflux in cells [PMID:31697912]. Beyond homodimers, TMEM163 heterodimerizes with ZNT1, ZNT2, and ZNT3 to form functional efflux units [PMID:36204728], and it physically interacts with the TRPML1 channel to cooperatively set intracellular zinc levels [PMID:25130899]. The protein distributes across synaptic vesicles, the plasma membrane, lysosomes, and early endosomes [PMID:17623043, PMID:21668449, PMID:35455965], and its sorting to lysosome-related organelles is directed by an N-terminal acidic dileucine motif that engages the BLOC-1 and AP-3 complexes through competitive, sequential binding; disruption of this motif strands the protein at the plasma membrane [PMID:41985787]. Through this zinc-handling activity TMEM163 functions in diverse physiological contexts, including modulation of ATP-gated P2X receptor pharmacology and pain behavior [PMID:32492420], zinc-regulated insulin storage and secretion in pancreatic beta cells [PMID:31813547], and vesicular zinc release from dorsal root ganglion neurons that tunes spinal itch circuits [PMID:39602426]. Heterozygous missense variants in its conserved cytoplasmic domain impair zinc efflux and cause hypomyelinating leukodystrophy, with mutant protein disrupting myelin gene expression and oligodendrocyte development in cells and zebrafish [PMID:35953447, PMID:35455965].","teleology":[{"year":2007,"claim":"Established TMEM163 as a bona fide membrane protein with a defined subcellular home, anchoring all later functional work in synaptic vesicle biology.","evidence":"Subcellular fractionation, immunoelectron microscopy, and immunocytochemistry of brain identifying SV31 on synaptic vesicles of glutamatergic and GABAergic terminals","pmids":["17623043"],"confidence":"High","gaps":["No transport activity or substrate demonstrated","Topology and oligomeric state unresolved"]},{"year":2011,"claim":"Defined the substrate selectivity of the protein, showing it binds Zn2+ and Ni2+ but not Ca2+/Fe2+/Mn2+, pointing toward a zinc-handling role.","evidence":"Recombinant metal-binding assays plus PC12 cell localization with FluoZin-3 and vesicle/endosome markers","pmids":["21668449"],"confidence":"High","gaps":["Binding does not establish vectorial transport","Direction of zinc flux not determined"]},{"year":2014,"claim":"Connected TMEM163 to a known lysosomal channel, revealing it acts cooperatively rather than in isolation to control cellular zinc.","evidence":"Yeast two-hybrid, Co-IP/MS, N-terminal deletion mutagenesis, and zinc assays with TRPML1 co-expression and knockdown in HEK-293 cells","pmids":["25130899"],"confidence":"High","gaps":["Stoichiometry of the TMEM163–TRPML1 interaction unknown","Whether interaction modulates transport kinetics not tested"]},{"year":2016,"claim":"Resolved the core transport mechanism, showing the protein is a proton-dependent zinc transporter whose dimerization and conserved acidic/histidine residues drive zinc binding.","evidence":"Cell-free synthesis, nanodisc and proteoliposome reconstitution, native MS, and site-directed mutagenesis with FluoZin transport assays","pmids":["27917477"],"confidence":"High","gaps":["High-resolution structure not determined","Coupling stoichiometry of H+/Zn2+ not quantified"]},{"year":2019,"claim":"Established TMEM163 as a zinc efflux transporter in human cells and placed it phylogenetically in the CDF/SLC30 family with key transport residues identified.","evidence":"Stable/transient expression with two fluorescent zinc dyes and 65Zn radionuclide efflux, D124A/D128A and E286K mutagenesis, and phylogenetics","pmids":["31697912"],"confidence":"High","gaps":["In vivo physiological substrate flux contexts not yet defined","Regulation of transporter activity unknown"]},{"year":2019,"claim":"Linked transporter activity to a physiological output, implicating TMEM163 in zinc-regulated insulin storage and secretion.","evidence":"siRNA knockdown in MIN6 beta cells with zinc, insulin content/secretion, and glucose uptake readouts","pmids":["31813547"],"confidence":"Medium","gaps":["No reconstitution or mutagenesis to establish direct mechanism","Effect on whole-organism glucose homeostasis untested"]},{"year":2020,"claim":"Revealed a signaling role beyond bulk zinc transport, showing TMEM163 modulates ATP-gated P2X receptor pharmacology and pain behavior.","evidence":"Genome-wide ORF functional screen with channel property assessment and in vivo pain behavioral assays","pmids":["32492420"],"confidence":"Medium","gaps":["Molecular basis of P2XR modulation not detailed","Whether modulation requires zinc transport activity unknown"]},{"year":2022,"claim":"Identified TMEM163 as a disease gene, demonstrating that zinc efflux deficiency in oligodendrocytes causes hypomyelinating leukodystrophy.","evidence":"Whole exome sequencing across families, in vitro zinc efflux assays of disease variants, and oligodendroglial expression with myelin gene, branching, and viability readouts; complemented by zebrafish tmem163a/b knockdown with human mRNA rescue","pmids":["35953447","35455965"],"confidence":"High","gaps":["Mechanism linking neuronal zinc dyshomeostasis to myelin gene downregulation incomplete","Variant-specific gain- vs loss-of-function effects on the same disease not reconciled"]},{"year":2022,"claim":"Showed TMEM163 partners with other zinc transporters, expanding its functional repertoire to heterodimeric efflux units.","evidence":"Reciprocal Co-IP with peptide tags, confocal co-localization, surface biotinylation, and zinc flux assays with ZNT1/2/3","pmids":["36204728"],"confidence":"Medium","gaps":["Single-lab reciprocal Co-IP","ZNT4 heterodimerization not definitively excluded","Physiological relevance of specific heterodimers in tissue not shown"]},{"year":2024,"claim":"Placed TMEM163 in an in vivo neural circuit, showing vesicular zinc release from sensory neurons regulates spinal itch processing.","evidence":"Immunofluorescence, fluorescent zinc imaging, neuron-specific analysis, spinal interneuron electrophysiology, and in vivo zinc chelation in aged mice","pmids":["39602426"],"confidence":"Medium","gaps":["Abstract-level mechanistic detail","Direct requirement of TMEM163 transport activity for itch not fully isolated"]},{"year":2025,"claim":"Extended the cooperative-transporter model to injury, showing TMEM163–ZnT3 interaction drives zinc dyshomeostasis in ischemic neurons.","evidence":"Co-IP, gain- and loss-of-function in rat primary hippocampal neurons under OGD with FluoZin-3, MTT, TUNEL, and surface biotinylation readouts","pmids":["41504061"],"confidence":"Medium","gaps":["Single-lab study","Trigger for membrane-to-cytoplasm translocation under OGD unknown"]},{"year":2026,"claim":"Defined the trafficking logic, showing an N-terminal acidic dileucine motif routes TMEM163 to lysosome-related organelles via competitive, sequential AP-3 and BLOC-1 engagement.","evidence":"Dileucine motif mutagenesis, reciprocal Co-IP across AP and BLOC complexes, confocal localization in trafficking-deficient MEG-01 cells, and proteasome inhibition assays","pmids":["41985787"],"confidence":"High","gaps":["Structural basis of competitive AP-3/BLOC-1 binding not resolved","Whether mislocalization alters zinc transport output not measured"]},{"year":null,"claim":"How the diverse phenotypes (leukodystrophy, itch, insulin secretion, ischemic injury, P2XR modulation) trace to a single transport mechanism, and whether they require zinc flux versus protein–protein interactions, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No high-resolution structure of the transporter","Tissue-specific heterodimer composition not mapped","Regulation of transporter activity and trafficking in vivo not established"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005215","term_label":"transporter activity","supporting_discovery_ids":[3,4,9]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,8,9,12]},{"term_id":"GO:0005764","term_label":"lysosome","supporting_discovery_ids":[8,12]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[2,8]},{"term_id":"GO:0031410","term_label":"cytoplasmic vesicle","supporting_discovery_ids":[1,8]}],"pathway":[{"term_id":"R-HSA-382551","term_label":"Transport of small molecules","supporting_discovery_ids":[3,4]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[12]}],"complexes":[],"partners":["TRPML1","ZNT1","ZNT2","ZNT3","AP-3","BLOC-1","P2X"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8TC26","full_name":"Transmembrane protein 163","aliases":[],"length_aa":289,"mass_kda":31.5,"function":"Zinc ion transporter that mediates zinc efflux and plays a crucial role in intracellular zinc homeostasis (PubMed:25130899, PubMed:31697912, PubMed:36204728). Binds the divalent cations Zn(2+), Ni(2+), and to a minor extent Cu(2+) (By similarity). Is a functional modulator of P2X purinoceptors, including P2RX1, P2RX3, P2RX4 and P2RX7 (PubMed:32492420). Plays a role in central nervous system development and is required for myelination, and survival and proliferation of oligodendrocytes (PubMed:35455965)","subcellular_location":"Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane; Early endosome membrane; Late endosome membrane; Lysosome membrane; Cell membrane","url":"https://www.uniprot.org/uniprotkb/Q8TC26/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/TMEM163","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TMEM163","total_profiled":1310},"omim":[{"mim_id":"620243","title":"LEUKODYSTROPHY, HYPOMYELINATING, 25; HLD25","url":"https://www.omim.org/entry/620243"},{"mim_id":"618978","title":"TRANSMEMBRANE PROTEIN 163; TMEM163","url":"https://www.omim.org/entry/618978"},{"mim_id":"605248","title":"MUCOLIPIN 1; MCOLN1","url":"https://www.omim.org/entry/605248"},{"mim_id":"312080","title":"PELIZAEUS-MERZBACHER DISEASE; PMD","url":"https://www.omim.org/entry/312080"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"brain","ntpm":44.4},{"tissue":"pancreas","ntpm":26.3}],"url":"https://www.proteinatlas.org/search/TMEM163"},"hgnc":{"alias_symbol":["DKFZP566N034","SV31","SLC30A11"],"prev_symbol":[]},"alphafold":{"accession":"Q8TC26","domains":[{"cath_id":"1.20.1510","chopping":"64-285","consensus_level":"high","plddt":85.0009,"start":64,"end":285}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8TC26","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8TC26-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8TC26-F1-predicted_aligned_error_v6.png","plddt_mean":76.5},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TMEM163","jax_strain_url":"https://www.jax.org/strain/search?query=TMEM163"},"sequence":{"accession":"Q8TC26","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8TC26.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8TC26/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8TC26"}},"corpus_meta":[{"pmid":"25130899","id":"PMC_25130899","title":"Cellular zinc levels are modulated by TRPML1-TMEM163 interaction.","date":"2014","source":"Traffic (Copenhagen, Denmark)","url":"https://pubmed.ncbi.nlm.nih.gov/25130899","citation_count":52,"is_preprint":false},{"pmid":"31697912","id":"PMC_31697912","title":"Transmembrane 163 (TMEM163) protein effluxes zinc.","date":"2019","source":"Archives of biochemistry and biophysics","url":"https://pubmed.ncbi.nlm.nih.gov/31697912","citation_count":29,"is_preprint":false},{"pmid":"17623043","id":"PMC_17623043","title":"Identification and characterization of SV31, a novel synaptic vesicle membrane protein and potential transporter.","date":"2007","source":"Journal of neurochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/17623043","citation_count":29,"is_preprint":false},{"pmid":"28199205","id":"PMC_28199205","title":"The mucolipin-1 (TRPML1) ion channel, transmembrane-163 (TMEM163) protein, and lysosomal zinc handling.","date":"2017","source":"Frontiers in bioscience (Landmark 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Behavior.","date":"2020","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/32492420","citation_count":17,"is_preprint":false},{"pmid":"33670071","id":"PMC_33670071","title":"Transmembrane 163 (TMEM163) Protein: A New Member of the Zinc Efflux Transporter Family.","date":"2021","source":"Biomedicines","url":"https://pubmed.ncbi.nlm.nih.gov/33670071","citation_count":16,"is_preprint":false},{"pmid":"31813547","id":"PMC_31813547","title":"Role of Tmem163 in zinc-regulated insulin storage of MIN6 cells: Functional exploration of an Indian type 2 diabetes GWAS associated gene.","date":"2019","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/31813547","citation_count":12,"is_preprint":false},{"pmid":"35455965","id":"PMC_35455965","title":"Functional Study of TMEM163 Gene Variants Associated with Hypomyelination Leukodystrophy.","date":"2022","source":"Cells","url":"https://pubmed.ncbi.nlm.nih.gov/35455965","citation_count":9,"is_preprint":false},{"pmid":"30719275","id":"PMC_30719275","title":"Polymorphisms of ACMSD-TMEM163, MCCC1, and BCKDK-STX1B Are Not Associated with Parkinson's Disease in Taiwan.","date":"2019","source":"Parkinson's disease","url":"https://pubmed.ncbi.nlm.nih.gov/30719275","citation_count":8,"is_preprint":false},{"pmid":"36204728","id":"PMC_36204728","title":"Transmembrane 163 (TMEM163) protein interacts with specific mammalian SLC30 zinc efflux transporter family members.","date":"2022","source":"Biochemistry and biophysics reports","url":"https://pubmed.ncbi.nlm.nih.gov/36204728","citation_count":5,"is_preprint":false},{"pmid":"35207731","id":"PMC_35207731","title":"PPARG, TMEM163, UBE2E2, and WFS1 Gene Polymorphisms Are Not Significant Risk Factors for Gestational Diabetes in the Polish Population.","date":"2022","source":"Journal of personalized medicine","url":"https://pubmed.ncbi.nlm.nih.gov/35207731","citation_count":4,"is_preprint":false},{"pmid":"39602426","id":"PMC_39602426","title":"Elevated vesicular Zn2+ in dorsal root ganglion neurons expressing the transporter TMEM163 causes age-associated itchy skin in mice.","date":"2024","source":"PLoS biology","url":"https://pubmed.ncbi.nlm.nih.gov/39602426","citation_count":3,"is_preprint":false},{"pmid":"39352626","id":"PMC_39352626","title":"The role of TMEM163 protein in thyroid microcarcinoma: expression pattern and clinical implications.","date":"2024","source":"Journal of endocrinological investigation","url":"https://pubmed.ncbi.nlm.nih.gov/39352626","citation_count":1,"is_preprint":false},{"pmid":"41504061","id":"PMC_41504061","title":"ZnT3-TMEM163 Mediates Zinc Homeostasis Imbalance Induced Neurodegeneration in Hippocampus.","date":"2025","source":"Frontiers in bioscience (Landmark edition)","url":"https://pubmed.ncbi.nlm.nih.gov/41504061","citation_count":0,"is_preprint":false},{"pmid":"41985787","id":"PMC_41985787","title":"A dileucine motif in TMEM163 is essential for its binding with both AP-3 and BLOC-1 complex.","date":"2026","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/41985787","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":10657,"output_tokens":4051,"usd":0.046368,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11892,"output_tokens":3988,"usd":0.07958,"stage2_stop_reason":"end_turn"},"total_usd":0.125948,"stage1_batch_id":"msgbatch_017qqVz33Ga63SCDwzb35XPb","stage2_batch_id":"msgbatch_01Scr2Ei9x4HJMiRGxwrmvLK","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2014,\n      \"finding\": \"TMEM163 physically interacts with TRPML1 ion channel, and this interaction depends on TMEM163's N-terminus (deletion of part of the N-terminus disrupts it). TRPML1 co-expression reduces plasma membrane levels of TMEM163, while a PM-retained TRPML1 mutant retains TMEM163 at the PM. TMEM163 knockdown or co-knockdown with TRPML1 causes significantly elevated intracellular zinc levels, demonstrating a cooperative role in cellular zinc homeostasis.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, mass spectrometry, confocal microscopy, N-terminal deletion mutagenesis, fluorescent zinc assays, siRNA knockdown in HEK-293 cells\",\n      \"journal\": \"Traffic (Copenhagen, Denmark)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (Y2H, Co-IP, MS, confocal, mutagenesis, functional zinc assays) in a single study with clear mechanistic readouts\",\n      \"pmids\": [\"25130899\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"TMEM163 (SV31) is a synaptic vesicle membrane protein of 31 kDa with six putative transmembrane helices, localized to synaptic vesicles in select brain regions including glutamatergic and GABAergic nerve terminals, as demonstrated by subcellular fractionation, immunocytochemistry of brain sections, and immunoelectron microscopy.\",\n      \"method\": \"Subcellular fractionation, heterologous expression, immunocytochemistry of brain sections, immunoelectron microscopy\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal localization methods (fractionation, IEM, ICC) consistently demonstrating synaptic vesicle localization\",\n      \"pmids\": [\"17623043\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"TMEM163 (SV31) binds divalent cations Zn2+ and Ni2+ and to a minor extent Cu2+, but not Fe2+, Co2+, Mn2+, or Ca2+. In PC12 cells, SV31-RFP partially co-fractionates with synaptic-like vesicle markers and early endosome marker Rab5, and localizes near the plasma membrane in a compartment positive for SNAP-25 and syntaxin1A.\",\n      \"method\": \"Recombinant protein metal-binding assays, heterologous transfection of PC12 cells, fluorescent zinc indicator (FluoZin-3), sucrose density gradient fractionation, immunocytochemistry\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct metal-binding assay combined with orthogonal localization methods (fractionation + ICC) in cellular context\",\n      \"pmids\": [\"21668449\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"TMEM163 (SV31) assembles into dimers when inserted into nanodisc bilayers, with dimerization increasing Zn2+ binding. Site-directed mutagenesis of two conserved aspartate residues markedly reduces Zn2+ binding but does not affect dimerization. Chemical modification of histidine residues also reduces Zn2+ binding. Reconstituted in proteoliposomes, SV31 mediates proton-dependent Zn2+ transport with a Km of 44.3 μM, requiring external Zn2+ and internal acidic pH.\",\n      \"method\": \"Cell-free protein synthesis, nanodisc reconstitution, site-directed mutagenesis, native mass spectrometry, proteoliposome transport assay with FluoZin-1\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution in proteoliposomes plus mutagenesis and structural characterization, multiple orthogonal methods establishing transport mechanism\",\n      \"pmids\": [\"27917477\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Human TMEM163 functions as a zinc efflux transporter in cells. Cells stably or transiently expressing TMEM163 show significantly reduced intracellular zinc levels as measured by two fluorescent zinc dyes and radionuclide 65Zn. Alanine substitution of two conserved aspartate residues (D124A/D128A) or the E286K variant significantly reduces zinc efflux, establishing these residues as important for transport function. Phylogenetic analysis places TMEM163 within the CDF/SLC30 zinc efflux family.\",\n      \"method\": \"Stable and transient expression in human cell lines, fluorescent zinc dyes (two independent), 65Zn radionuclide assay, TPEN chelation control, site-directed mutagenesis, sequence alignment and phylogenetics\",\n      \"journal\": \"Archives of biochemistry and biophysics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct zinc efflux demonstrated by three independent assays (two fluorescent dyes + radionuclide), functional mutagenesis identifying key residues\",\n      \"pmids\": [\"31697912\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Knockdown of endogenous Tmem163 in MIN6 pancreatic beta cells results in increased intracellular zinc, increased total insulin content, but compromised glucose-stimulated insulin secretion and enhanced cellular glucose uptake, placing TMEM163 in the pathway of zinc-regulated insulin storage and secretion.\",\n      \"method\": \"siRNA knockdown in MIN6 cells, intracellular zinc measurement, insulin content and secretion assays, glucose uptake assay\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean knockdown with multiple functional readouts in a single lab, but no reconstitution or mutagenesis to establish direct mechanism\",\n      \"pmids\": [\"31813547\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"TMEM163 specifically modulates the channel properties and pharmacology of ATP-gated P2X receptors (P2XRs) in vivo. Genome-wide ORF screening identified TMEM163 as a P2XR modulator; it is required for full function of neuronal P2XR and pain-related ATP-evoked behavior.\",\n      \"method\": \"Genome-wide ORF functional screen, electrophysiology (implied by channel property assessment), in vivo behavioral assays for pain\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genome-wide functional screen plus in vivo behavioral validation, but mechanistic details of how TMEM163 modulates P2XR are not fully detailed in the abstract\",\n      \"pmids\": [\"32492420\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Heterozygous missense variants in TMEM163 residing in the conserved cytoplasmic domain cause hypomyelinating leukodystrophy. Functional in vitro analysis shows significant impairment of zinc efflux by mutant proteins. Expression of mutant TMEM163 in an oligodendroglial cell line reduces mRNA expression of key myelin genes, decreases branching, and increases cell death, establishing a role for TMEM163-mediated zinc efflux in oligodendrocyte development.\",\n      \"method\": \"Whole exome sequencing, in vitro zinc efflux assays with disease variants, oligodendroglial cell line expression, qPCR for myelin genes, cell morphology and viability assays\",\n      \"journal\": \"Brain : a journal of neurology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct functional assay of disease variants plus oligodendrocyte cellular phenotype, replicated across four unrelated families with two orthogonal functional readouts\",\n      \"pmids\": [\"35953447\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Two de novo TMEM163 variants (L76R, L76P) cause hypomyelinating leukodystrophy. Functional zinc flux assays show L76R attenuates and L76P enhances zinc efflux. In zebrafish, knockdown of tmem163a/b causes myelin deficit, locomotor disability, and oligodendrocyte/neuron loss; wild-type human TMEM163 rescues the morphant phenotype, while L76R and L76P mutants fail to rescue or worsen it. TMEM163 localizes to the plasma membrane, lysosomes, early endosomes, and other vesicular compartments.\",\n      \"method\": \"Functional zinc flux assays (HeLa stable expression), zebrafish morphant model (siRNA knockdown of tmem163a/b), mRNA rescue experiments, locomotor assays, immunostaining for myelin and oligodendrocyte markers\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vitro functional assay plus in vivo zebrafish rescue with multiple orthogonal phenotypic readouts across two studies showing convergent findings\",\n      \"pmids\": [\"35455965\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"TMEM163 forms homodimers and heterodimerizes with ZNT1, ZNT2, and ZNT3, but not with ZNT4 (negative control for heterodimerization was not excluded). TMEM163 and ZNT proteins partially co-localize in cells. TMEM163/ZNT heterodimers exhibit similar zinc efflux function as TMEM163 homodimers. Plasma membrane localization of TMEM163 is not markedly altered by ZNT co-expression.\",\n      \"method\": \"Co-immunoprecipitation with unique peptide tags, Western blot, confocal microscopy co-localization, cell surface biotinylation, functional zinc flux assays (FluoZin-3, Newport Green)\",\n      \"journal\": \"Biochemistry and biophysics reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP with multiple ZNT partners plus functional and localization validation in a single lab\",\n      \"pmids\": [\"36204728\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TMEM163 is expressed in a subset of dorsal root ganglion neurons enriched with vesicular Zn2+. These neurons form direct synapses with spinal NPY+ inhibitory interneurons and modulate their activity. In aged mice, TMEM163 expression and vesicular Zn2+ concentration are elevated in central terminals of TMEM163+ afferents; excessive vesicular Zn2+ release dampens NPY+ interneuron activity, causing disinhibition of itch circuits and chronic itch. Zinc chelation in the spinal dorsal horn relieves itch in aged mice.\",\n      \"method\": \"Immunofluorescence, fluorescent zinc imaging, conditional knockout/neuron-specific analysis, electrophysiology of spinal interneurons, zinc chelation pharmacology in vivo (aged mice)\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo functional circuit experiments with pharmacological rescue, but abstract does not detail full mechanistic rigor (single lab, limited by abstract detail)\",\n      \"pmids\": [\"39602426\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ZnT3 and TMEM163 physically interact (co-immunoprecipitation confirmed) and cooperatively regulate zinc homeostasis in hippocampal neurons. Under oxygen-glucose deprivation (OGD), both proteins are upregulated and translocate from the cell membrane to the cytoplasm. Overexpression of TMEM163 exacerbates extracellular zinc efflux and neuronal apoptosis under OGD; silencing attenuates zinc overload and neurodegeneration. TMEM163 thus contributes to ischemia-induced neuronal injury via zinc dyshomeostasis.\",\n      \"method\": \"siRNA silencing and plasmid overexpression in rat primary hippocampal neurons, OGD model, MTT assay, TUNEL staining, FluoZin-3 zinc measurement, ELISA, co-immunoprecipitation, cell surface biotinylation, RT-qPCR, Western blot\",\n      \"journal\": \"Frontiers in bioscience (Landmark edition)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP plus gain-of-function and loss-of-function with multiple phenotypic readouts in primary neurons, single lab\",\n      \"pmids\": [\"41504061\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"A conserved N-terminal acidic dileucine motif (LEDRGL69L70) in TMEM163 is essential for interaction with BLOC-1 and AP-3 complexes but dispensable for binding AP-1, AP-2, and BLOC-2. Mutation of this motif causes TMEM163 accumulation at the plasma membrane. Loss of BLOC-1 or AP-3 enhances TMEM163 binding to the other complex and results in differential abnormal endo-lysosomal localization, indicating competitive binding and sequential sorting of TMEM163 by AP-3 and BLOC-1 to platelet dense granules. TMEM163 is degraded via the proteasome in cells lacking AP-1, AP-2, AP-3, BLOC-1, or BLOC-2.\",\n      \"method\": \"Co-immunoprecipitation, mutagenesis of dileucine motif, confocal microscopy subcellular localization, MEG-01 cell lines deficient in endosomal trafficking complexes, proteasome inhibition assays, cell surface biotinylation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — site-directed mutagenesis of sorting motif combined with reciprocal Co-IP across multiple complex members and subcellular localization readouts, establishing a defined trafficking mechanism\",\n      \"pmids\": [\"41985787\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TMEM163 is a zinc efflux transporter (designated ZNT11/SLC30A11) belonging to the CDF/SLC30 family that forms homodimers and heterodimers with ZNT1–3; it localizes to the plasma membrane, lysosomes, early endosomes, and synaptic vesicles via a dileucine sorting motif that engages AP-3 and BLOC-1 for trafficking to lysosome-related organelles; two conserved aspartate residues (D124/D128) and E286 are critical for its proton-dependent zinc efflux activity; it interacts with TRPML1 to cooperatively regulate lysosomal zinc homeostasis, modulates ATP-gated P2X receptor pharmacology, mediates vesicular zinc release in dorsal root ganglion neurons to regulate itch circuits, and its loss-of-function variants impair oligodendrocyte zinc homeostasis causing hypomyelinating leukodystrophy.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TMEM163 (SV31, ZNT11/SLC30A11) is a proton-coupled zinc efflux transporter of the CDF/SLC30 family that controls cellular and vesicular zinc homeostasis [#4]. Reconstitution in proteoliposomes establishes that it mediates Zn2+ transport that depends on external zinc and an internal acidic pH, with transport activity assembling on the homodimer; two conserved aspartate residues and histidine residues are required for zinc binding [#3], and alanine substitution of these aspartates (D124A/D128A) or the E286K variant abolishes efflux in cells [#4]. Beyond homodimers, TMEM163 heterodimerizes with ZNT1, ZNT2, and ZNT3 to form functional efflux units [#9], and it physically interacts with the TRPML1 channel to cooperatively set intracellular zinc levels [#0]. The protein distributes across synaptic vesicles, the plasma membrane, lysosomes, and early endosomes [#1, #2, #8], and its sorting to lysosome-related organelles is directed by an N-terminal acidic dileucine motif that engages the BLOC-1 and AP-3 complexes through competitive, sequential binding; disruption of this motif strands the protein at the plasma membrane [#12]. Through this zinc-handling activity TMEM163 functions in diverse physiological contexts, including modulation of ATP-gated P2X receptor pharmacology and pain behavior [#6], zinc-regulated insulin storage and secretion in pancreatic beta cells [#5], and vesicular zinc release from dorsal root ganglion neurons that tunes spinal itch circuits [#10]. Heterozygous missense variants in its conserved cytoplasmic domain impair zinc efflux and cause hypomyelinating leukodystrophy, with mutant protein disrupting myelin gene expression and oligodendrocyte development in cells and zebrafish [#7, #8].\",\n  \"teleology\": [\n    {\n      \"year\": 2007,\n      \"claim\": \"Established TMEM163 as a bona fide membrane protein with a defined subcellular home, anchoring all later functional work in synaptic vesicle biology.\",\n      \"evidence\": \"Subcellular fractionation, immunoelectron microscopy, and immunocytochemistry of brain identifying SV31 on synaptic vesicles of glutamatergic and GABAergic terminals\",\n      \"pmids\": [\"17623043\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No transport activity or substrate demonstrated\", \"Topology and oligomeric state unresolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Defined the substrate selectivity of the protein, showing it binds Zn2+ and Ni2+ but not Ca2+/Fe2+/Mn2+, pointing toward a zinc-handling role.\",\n      \"evidence\": \"Recombinant metal-binding assays plus PC12 cell localization with FluoZin-3 and vesicle/endosome markers\",\n      \"pmids\": [\"21668449\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Binding does not establish vectorial transport\", \"Direction of zinc flux not determined\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Connected TMEM163 to a known lysosomal channel, revealing it acts cooperatively rather than in isolation to control cellular zinc.\",\n      \"evidence\": \"Yeast two-hybrid, Co-IP/MS, N-terminal deletion mutagenesis, and zinc assays with TRPML1 co-expression and knockdown in HEK-293 cells\",\n      \"pmids\": [\"25130899\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry of the TMEM163–TRPML1 interaction unknown\", \"Whether interaction modulates transport kinetics not tested\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Resolved the core transport mechanism, showing the protein is a proton-dependent zinc transporter whose dimerization and conserved acidic/histidine residues drive zinc binding.\",\n      \"evidence\": \"Cell-free synthesis, nanodisc and proteoliposome reconstitution, native MS, and site-directed mutagenesis with FluoZin transport assays\",\n      \"pmids\": [\"27917477\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"High-resolution structure not determined\", \"Coupling stoichiometry of H+/Zn2+ not quantified\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Established TMEM163 as a zinc efflux transporter in human cells and placed it phylogenetically in the CDF/SLC30 family with key transport residues identified.\",\n      \"evidence\": \"Stable/transient expression with two fluorescent zinc dyes and 65Zn radionuclide efflux, D124A/D128A and E286K mutagenesis, and phylogenetics\",\n      \"pmids\": [\"31697912\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo physiological substrate flux contexts not yet defined\", \"Regulation of transporter activity unknown\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Linked transporter activity to a physiological output, implicating TMEM163 in zinc-regulated insulin storage and secretion.\",\n      \"evidence\": \"siRNA knockdown in MIN6 beta cells with zinc, insulin content/secretion, and glucose uptake readouts\",\n      \"pmids\": [\"31813547\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No reconstitution or mutagenesis to establish direct mechanism\", \"Effect on whole-organism glucose homeostasis untested\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Revealed a signaling role beyond bulk zinc transport, showing TMEM163 modulates ATP-gated P2X receptor pharmacology and pain behavior.\",\n      \"evidence\": \"Genome-wide ORF functional screen with channel property assessment and in vivo pain behavioral assays\",\n      \"pmids\": [\"32492420\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular basis of P2XR modulation not detailed\", \"Whether modulation requires zinc transport activity unknown\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified TMEM163 as a disease gene, demonstrating that zinc efflux deficiency in oligodendrocytes causes hypomyelinating leukodystrophy.\",\n      \"evidence\": \"Whole exome sequencing across families, in vitro zinc efflux assays of disease variants, and oligodendroglial expression with myelin gene, branching, and viability readouts; complemented by zebrafish tmem163a/b knockdown with human mRNA rescue\",\n      \"pmids\": [\"35953447\", \"35455965\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism linking neuronal zinc dyshomeostasis to myelin gene downregulation incomplete\", \"Variant-specific gain- vs loss-of-function effects on the same disease not reconciled\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Showed TMEM163 partners with other zinc transporters, expanding its functional repertoire to heterodimeric efflux units.\",\n      \"evidence\": \"Reciprocal Co-IP with peptide tags, confocal co-localization, surface biotinylation, and zinc flux assays with ZNT1/2/3\",\n      \"pmids\": [\"36204728\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab reciprocal Co-IP\", \"ZNT4 heterodimerization not definitively excluded\", \"Physiological relevance of specific heterodimers in tissue not shown\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Placed TMEM163 in an in vivo neural circuit, showing vesicular zinc release from sensory neurons regulates spinal itch processing.\",\n      \"evidence\": \"Immunofluorescence, fluorescent zinc imaging, neuron-specific analysis, spinal interneuron electrophysiology, and in vivo zinc chelation in aged mice\",\n      \"pmids\": [\"39602426\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Abstract-level mechanistic detail\", \"Direct requirement of TMEM163 transport activity for itch not fully isolated\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Extended the cooperative-transporter model to injury, showing TMEM163–ZnT3 interaction drives zinc dyshomeostasis in ischemic neurons.\",\n      \"evidence\": \"Co-IP, gain- and loss-of-function in rat primary hippocampal neurons under OGD with FluoZin-3, MTT, TUNEL, and surface biotinylation readouts\",\n      \"pmids\": [\"41504061\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"Trigger for membrane-to-cytoplasm translocation under OGD unknown\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Defined the trafficking logic, showing an N-terminal acidic dileucine motif routes TMEM163 to lysosome-related organelles via competitive, sequential AP-3 and BLOC-1 engagement.\",\n      \"evidence\": \"Dileucine motif mutagenesis, reciprocal Co-IP across AP and BLOC complexes, confocal localization in trafficking-deficient MEG-01 cells, and proteasome inhibition assays\",\n      \"pmids\": [\"41985787\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of competitive AP-3/BLOC-1 binding not resolved\", \"Whether mislocalization alters zinc transport output not measured\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the diverse phenotypes (leukodystrophy, itch, insulin secretion, ischemic injury, P2XR modulation) trace to a single transport mechanism, and whether they require zinc flux versus protein–protein interactions, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No high-resolution structure of the transporter\", \"Tissue-specific heterodimer composition not mapped\", \"Regulation of transporter activity and trafficking in vivo not established\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005215\", \"supporting_discovery_ids\": [3, 4, 9]},\n      {\"term_id\": \"GO:0046873\", \"supporting_discovery_ids\": [3, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 8, 9, 12]},\n      {\"term_id\": \"GO:0005764\", \"supporting_discovery_ids\": [8, 12]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [2, 8]},\n      {\"term_id\": \"GO:0031410\", \"supporting_discovery_ids\": [1, 8]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-382551\", \"supporting_discovery_ids\": [3, 4]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [12]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TRPML1\", \"ZNT1\", \"ZNT2\", \"ZNT3\", \"AP-3\", \"BLOC-1\", \"P2X\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}