{"gene":"TMED4","run_date":"2026-06-10T10:51:55","timeline":{"discoveries":[{"year":2024,"finding":"TMED4 (p24alpha3) maintains Treg suppressive function and Foxp3 stability by preventing excessive ROS accumulation through an IRE1α/XBP1 axis-dependent endoplasmic reticulum stress and NRF2-related antioxidant response; Treg-specific knockout of TMED4 caused defects in ERS and the NRF2 antioxidant response, which could be rescued by ROS scavenger, NRF2 inducer, or forced IRE1α expression. Additionally, TMED4 suppresses IRE1α proteasomal degradation via the ERAD system, involving the ER chaperone BIP.","method":"Treg-specific conditional knockout mice (Tmed4ΔTreg), ROS measurements, rescue experiments with ROS scavenger/NRF2 inducer/forced IRE1α expression, co-immunoprecipitation/interaction studies with BIP and IRE1α, functional suppression assays","journal":"The Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO with defined cellular phenotype, multiple orthogonal rescue experiments (ROS scavenger, NRF2 inducer, forced IRE1α), and molecular mechanism identified via ERAD/BIP interaction in a single rigorous study","pmids":["39480507"],"is_preprint":false},{"year":2007,"finding":"Transgenic overexpression of p24alpha3 (TMED4 ortholog) in Xenopus melanotrope cells displaced endogenous p24 proteins, greatly reduced POMC transport, and led to accumulation of prohormone in large ER-localized electron-dense structures, demonstrating a specific role for p24alpha3 in ER-to-Golgi secretory protein transport distinct from p24delta2.","method":"Xenopus transgenic overexpression (melanotrope cell-specific), electron microscopy, pulse-chase POMC transport assays, endogenous p24 protein level analysis","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — transgenic in vivo model with multiple cellular readouts (ultrastructure, cargo transport, endogenous protein levels), single lab","pmids":["17684551"],"is_preprint":false},{"year":2009,"finding":"p24alpha3 (TMED4 ortholog) has non-redundant roles compared to other p24 subfamily members (beta1, gamma3, delta2) in the early secretory pathway; transgenic expression of p24alpha3 reduced cargo (POMC) cleavage rate without affecting Golgi-based glycosylation and sulfation, while other subfamily members showed distinct or overlapping effects, indicating each p24 member provides a distinct ER/Golgi subcompartmental microenvironment.","method":"Xenopus melanotrope cell-specific transgenic expression, POMC transport/cleavage assays, glycosylation/sulfation analysis, endogenous p24 protein level measurements","journal":"Biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — comparative transgenic approach across multiple p24 family members with defined cargo readouts, single lab, multiple orthogonal assays","pmids":["18699773"],"is_preprint":false},{"year":2010,"finding":"p24alpha3 (TMED4 ortholog) is functionally non-redundant with other members of the same subfamily; its role in POMC transport, glycosylation, sulfation, and cleavage in melanotrope cells differs from those of p24gamma2 and p24delta1, confirming that even intra-subfamily p24 members have distinct functions.","method":"Xenopus melanotrope cell-specific transgenic expression, POMC biosynthesis assays (transport, cleavage, glycosylation, sulfation)","journal":"Biochimie","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — transgenic model with multiple cargo biosynthesis readouts, single lab, extends prior findings","pmids":["21118709"],"is_preprint":false},{"year":2015,"finding":"TMED4/p25 localizes to the Golgi in male germ cells and continues to mark Golgi identity as it migrates away from the acrosome during spermatid differentiation, in contrast to other Golgi proteins (GBF1, GPP34, GRASP55) that become sequestered in the acrosome and are subsequently lost.","method":"Golgi fraction isolation from germ cells, mass spectrometry protein identification, in situ immunolocalization during acrosome formation and spermatid differentiation","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — direct subcellular localization by fractionation and in situ imaging across multiple differentiation stages, single lab, no functional manipulation of TMED4 specifically","pmids":["25808494"],"is_preprint":false}],"current_model":"TMED4 (p24alpha3) is a transmembrane p24 family protein that functions at the ER-Golgi interface to facilitate secretory protein transport and processing in a non-redundant manner relative to other p24 subfamily members; in immune cells, TMED4 maintains regulatory T cell Foxp3 stability and suppressive function by sustaining IRE1α protein levels (via BIP-dependent ERAD) and thereby enabling the IRE1α/XBP1-dependent ER stress and NRF2-mediated antioxidant responses that limit excessive ROS accumulation."},"narrative":{"mechanistic_narrative":"TMED4 (p24alpha3) is a transmembrane p24 family protein that operates at the ER-Golgi interface to confer specificity on secretory protein transport and processing [PMID:17684551, PMID:18699773]. Transgenic overexpression in Xenopus melanotrope cells displaces endogenous p24 proteins, blocks transport of the prohormone POMC, and causes prohormone accumulation in ER-localized electron-dense structures, establishing a non-redundant role in ER-to-Golgi cargo trafficking distinct from other p24 subfamily and intra-subfamily members [PMID:17684551, PMID:18699773, PMID:21118709]. Consistent with a constitutive role in early secretory compartments, TMED4 marks Golgi identity in differentiating male germ cells and remains associated with the migrating Golgi during spermatogenesis [PMID:25808494]. Beyond trafficking, TMED4 sustains regulatory T cell function: it maintains Foxp3 stability and suppressive activity by limiting ROS accumulation, acting through stabilization of IRE1α — TMED4 suppresses IRE1α proteasomal degradation via BIP-dependent ERAD — and thereby enabling IRE1α/XBP1-dependent ER stress signaling and the NRF2 antioxidant response [PMID:39480507].","teleology":[{"year":2007,"claim":"Whether p24alpha3 has a dedicated role in secretory cargo transport, as opposed to being a redundant p24 family member, was unresolved; this established it as a specific factor required for ER-to-Golgi prohormone transport.","evidence":"Melanotrope-specific transgenic overexpression in Xenopus with electron microscopy and pulse-chase POMC transport assays","pmids":["17684551"],"confidence":"Medium","gaps":["Mechanism of cargo selection by p24alpha3 not defined","Findings rest on overexpression/displacement rather than loss of function","Human TMED4 not directly assayed"]},{"year":2009,"claim":"It was unclear whether individual p24 members provided distinct versus overlapping secretory functions; comparative transgenics showed p24alpha3 affects cargo cleavage without altering Golgi glycosylation/sulfation, indicating each member shapes a distinct ER/Golgi microenvironment.","evidence":"Comparative transgenic expression of multiple p24 subfamily members in Xenopus melanotropes with POMC biosynthesis readouts","pmids":["18699773"],"confidence":"Medium","gaps":["Biochemical basis of the distinct microenvironment unknown","Single lab and single cargo (POMC)","No direct partner mapping among p24 members"]},{"year":2010,"claim":"Whether functional distinctions extended within the same p24 subfamily was open; this confirmed intra-subfamily non-redundancy of p24alpha3 relative to p24gamma2 and p24delta1 across transport, cleavage, glycosylation and sulfation.","evidence":"Xenopus melanotrope transgenic expression with POMC transport, cleavage, glycosylation, and sulfation assays","pmids":["21118709"],"confidence":"Medium","gaps":["Structural determinants of subfamily-specific function not identified","Overexpression-based inference","Not tested in mammalian cells"]},{"year":2015,"claim":"The subcellular behavior of TMED4 in a specialized differentiating cell type was unknown; localization showed it stably marks Golgi identity during spermatid differentiation unlike other Golgi proteins lost to the acrosome.","evidence":"Golgi fractionation with mass spectrometry and in situ immunolocalization across spermatid differentiation stages","pmids":["25808494"],"confidence":"Medium","gaps":["No functional manipulation of TMED4 in germ cells","Role in acrosome biogenesis not tested","Mechanism of Golgi retention unclear"]},{"year":2024,"claim":"Whether TMED4 had functions beyond canonical trafficking was unknown; Treg-specific knockout revealed it sustains IRE1α levels via BIP-dependent ERAD suppression, driving IRE1α/XBP1 ER-stress and NRF2 antioxidant responses to limit ROS and preserve Foxp3 stability and Treg suppression.","evidence":"Treg-specific conditional knockout mice, ROS measurements, rescue with ROS scavenger/NRF2 inducer/forced IRE1α, and co-IP with BIP and IRE1α","pmids":["39480507"],"confidence":"High","gaps":["How TMED4 mechanistically blocks IRE1α ERAD is not resolved","Direct binding versus indirect stabilization of IRE1α not distinguished","Link between trafficking role and IRE1α stabilization unestablished"]},{"year":null,"claim":"It remains unknown how TMED4's role in ER-to-Golgi cargo transport mechanistically connects to its stabilization of IRE1α and control of ER stress/antioxidant signaling.","evidence":"","pmids":[],"confidence":"High","gaps":["No unified molecular model linking trafficking and IRE1α stabilization","Human TMED4 substrate repertoire uncharacterized","Structural basis of p24alpha3 specificity unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0038024","term_label":"cargo receptor activity","supporting_discovery_ids":[1,2,3]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[4]},{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[1,0]}],"pathway":[{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[1,2,3]},{"term_id":"R-HSA-8953897","term_label":"Cellular responses to stimuli","supporting_discovery_ids":[0]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[0]}],"complexes":[],"partners":["IRE1A","HSPA5"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q7Z7H5","full_name":"Transmembrane emp24 domain-containing protein 4","aliases":["Endoplasmic reticulum stress-response protein 25","ERS25","GMP25iso","Putative NF-kappa-B-activating protein 156","p24 family protein alpha-3","p24alpha3"],"length_aa":227,"mass_kda":25.9,"function":"Involved in vesicular protein trafficking, mainly in the early secretory pathway. targeting. Involved in the maintenance of the Golgi apparatus. Appears to play a role in the biosynthesis of secreted cargo including processing. Involved in endoplasmic reticulum stress response. May play a role in the regulation of heat-shock response and apoptosis (By similarity)","subcellular_location":"Endoplasmic reticulum membrane","url":"https://www.uniprot.org/uniprotkb/Q7Z7H5/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/TMED4","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":[{"gene":"TMED10","stoichiometry":10.0},{"gene":"TMED2","stoichiometry":10.0},{"gene":"GOLGA2","stoichiometry":0.2},{"gene":"GORASP2","stoichiometry":0.2},{"gene":"MYBBP1A","stoichiometry":0.2},{"gene":"RAB1A","stoichiometry":0.2},{"gene":"YIPF5","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/TMED4","total_profiled":1310},"omim":[{"mim_id":"612038","title":"TRANSMEMBRANE p24 TRAFFICKING PROTEIN 4; TMED4","url":"https://www.omim.org/entry/612038"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TMED4"},"hgnc":{"alias_symbol":["HNLF","p24alpha3","p24a3"],"prev_symbol":[]},"alphafold":{"accession":"Q7Z7H5","domains":[{"cath_id":"2.60.120.680","chopping":"30-175","consensus_level":"medium","plddt":85.7688,"start":30,"end":175}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q7Z7H5","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q7Z7H5-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q7Z7H5-F1-predicted_aligned_error_v6.png","plddt_mean":85.19},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TMED4","jax_strain_url":"https://www.jax.org/strain/search?query=TMED4"},"sequence":{"accession":"Q7Z7H5","fasta_url":"https://rest.uniprot.org/uniprotkb/Q7Z7H5.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q7Z7H5/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q7Z7H5"}},"corpus_meta":[{"pmid":"18699773","id":"PMC_18699773","title":"Functional diversity among p24 subfamily members.","date":"2009","source":"Biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/18699773","citation_count":30,"is_preprint":false},{"pmid":"25808494","id":"PMC_25808494","title":"Expression, sorting, and segregation of Golgi proteins during germ cell differentiation in the testis.","date":"2015","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/25808494","citation_count":23,"is_preprint":false},{"pmid":"39480507","id":"PMC_39480507","title":"TMED4 facilitates regulatory T cell suppressive function via ROS homeostasis in tumor and autoimmune mouse models.","date":"2024","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/39480507","citation_count":18,"is_preprint":false},{"pmid":"17684551","id":"PMC_17684551","title":"Disparate effects of p24alpha and p24delta on secretory protein transport and processing.","date":"2007","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/17684551","citation_count":16,"is_preprint":false},{"pmid":"23076522","id":"PMC_23076522","title":"Interactive cellular proteins related to classical swine fever virus non-structure protein 2 by yeast two-hybrid analysis.","date":"2012","source":"Molecular biology reports","url":"https://pubmed.ncbi.nlm.nih.gov/23076522","citation_count":13,"is_preprint":false},{"pmid":"37649561","id":"PMC_37649561","title":"Identification of a diagnostic model and molecular subtypes of major depressive disorder based on endoplasmic reticulum stress-related genes.","date":"2023","source":"Frontiers in psychiatry","url":"https://pubmed.ncbi.nlm.nih.gov/37649561","citation_count":8,"is_preprint":false},{"pmid":"19401156","id":"PMC_19401156","title":"COP-binding sites in p24delta2 are necessary for proper secretory cargo biosynthesis.","date":"2009","source":"The international journal of biochemistry & cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/19401156","citation_count":7,"is_preprint":false},{"pmid":"14506938","id":"PMC_14506938","title":"In vitro reactive nitrating species toxicity in dissociated spinal motor neurons from NFL (-/-) and hNFL (+/+) transgenic mice.","date":"2003","source":"Amyotrophic lateral sclerosis and other motor neuron disorders : official publication of the World Federation of Neurology, Research Group on Motor Neuron Diseases","url":"https://pubmed.ncbi.nlm.nih.gov/14506938","citation_count":7,"is_preprint":false},{"pmid":"21118709","id":"PMC_21118709","title":"p24 Proteins from the same subfamily are functionally nonredundant.","date":"2010","source":"Biochimie","url":"https://pubmed.ncbi.nlm.nih.gov/21118709","citation_count":5,"is_preprint":false},{"pmid":"26191769","id":"PMC_26191769","title":"Photonic approach for microwave frequency measurement with adjustable measurement range and resolution using birefringence effect in highly non-linear fiber.","date":"2015","source":"Optics express","url":"https://pubmed.ncbi.nlm.nih.gov/26191769","citation_count":4,"is_preprint":false},{"pmid":"40778317","id":"PMC_40778317","title":"Integrative machine learning approach for forecasting lung cancer chemosensitivity: From algorithm to cell line validation.","date":"2025","source":"Computational and structural biotechnology journal","url":"https://pubmed.ncbi.nlm.nih.gov/40778317","citation_count":1,"is_preprint":false},{"pmid":"21743511","id":"PMC_21743511","title":"All-fiber magneto-optic Sagnac interferometer.","date":"2011","source":"Applied optics","url":"https://pubmed.ncbi.nlm.nih.gov/21743511","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":7523,"output_tokens":1529,"usd":0.022752,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":8294,"output_tokens":2359,"usd":0.050223,"stage2_stop_reason":"end_turn"},"total_usd":0.072975,"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\": 2024,\n      \"finding\": \"TMED4 (p24alpha3) maintains Treg suppressive function and Foxp3 stability by preventing excessive ROS accumulation through an IRE1α/XBP1 axis-dependent endoplasmic reticulum stress and NRF2-related antioxidant response; Treg-specific knockout of TMED4 caused defects in ERS and the NRF2 antioxidant response, which could be rescued by ROS scavenger, NRF2 inducer, or forced IRE1α expression. Additionally, TMED4 suppresses IRE1α proteasomal degradation via the ERAD system, involving the ER chaperone BIP.\",\n      \"method\": \"Treg-specific conditional knockout mice (Tmed4ΔTreg), ROS measurements, rescue experiments with ROS scavenger/NRF2 inducer/forced IRE1α expression, co-immunoprecipitation/interaction studies with BIP and IRE1α, functional suppression assays\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO with defined cellular phenotype, multiple orthogonal rescue experiments (ROS scavenger, NRF2 inducer, forced IRE1α), and molecular mechanism identified via ERAD/BIP interaction in a single rigorous study\",\n      \"pmids\": [\"39480507\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Transgenic overexpression of p24alpha3 (TMED4 ortholog) in Xenopus melanotrope cells displaced endogenous p24 proteins, greatly reduced POMC transport, and led to accumulation of prohormone in large ER-localized electron-dense structures, demonstrating a specific role for p24alpha3 in ER-to-Golgi secretory protein transport distinct from p24delta2.\",\n      \"method\": \"Xenopus transgenic overexpression (melanotrope cell-specific), electron microscopy, pulse-chase POMC transport assays, endogenous p24 protein level analysis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — transgenic in vivo model with multiple cellular readouts (ultrastructure, cargo transport, endogenous protein levels), single lab\",\n      \"pmids\": [\"17684551\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"p24alpha3 (TMED4 ortholog) has non-redundant roles compared to other p24 subfamily members (beta1, gamma3, delta2) in the early secretory pathway; transgenic expression of p24alpha3 reduced cargo (POMC) cleavage rate without affecting Golgi-based glycosylation and sulfation, while other subfamily members showed distinct or overlapping effects, indicating each p24 member provides a distinct ER/Golgi subcompartmental microenvironment.\",\n      \"method\": \"Xenopus melanotrope cell-specific transgenic expression, POMC transport/cleavage assays, glycosylation/sulfation analysis, endogenous p24 protein level measurements\",\n      \"journal\": \"Biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — comparative transgenic approach across multiple p24 family members with defined cargo readouts, single lab, multiple orthogonal assays\",\n      \"pmids\": [\"18699773\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"p24alpha3 (TMED4 ortholog) is functionally non-redundant with other members of the same subfamily; its role in POMC transport, glycosylation, sulfation, and cleavage in melanotrope cells differs from those of p24gamma2 and p24delta1, confirming that even intra-subfamily p24 members have distinct functions.\",\n      \"method\": \"Xenopus melanotrope cell-specific transgenic expression, POMC biosynthesis assays (transport, cleavage, glycosylation, sulfation)\",\n      \"journal\": \"Biochimie\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — transgenic model with multiple cargo biosynthesis readouts, single lab, extends prior findings\",\n      \"pmids\": [\"21118709\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"TMED4/p25 localizes to the Golgi in male germ cells and continues to mark Golgi identity as it migrates away from the acrosome during spermatid differentiation, in contrast to other Golgi proteins (GBF1, GPP34, GRASP55) that become sequestered in the acrosome and are subsequently lost.\",\n      \"method\": \"Golgi fraction isolation from germ cells, mass spectrometry protein identification, in situ immunolocalization during acrosome formation and spermatid differentiation\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — direct subcellular localization by fractionation and in situ imaging across multiple differentiation stages, single lab, no functional manipulation of TMED4 specifically\",\n      \"pmids\": [\"25808494\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TMED4 (p24alpha3) is a transmembrane p24 family protein that functions at the ER-Golgi interface to facilitate secretory protein transport and processing in a non-redundant manner relative to other p24 subfamily members; in immune cells, TMED4 maintains regulatory T cell Foxp3 stability and suppressive function by sustaining IRE1α protein levels (via BIP-dependent ERAD) and thereby enabling the IRE1α/XBP1-dependent ER stress and NRF2-mediated antioxidant responses that limit excessive ROS accumulation.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TMED4 (p24alpha3) is a transmembrane p24 family protein that operates at the ER-Golgi interface to confer specificity on secretory protein transport and processing [#1, #2]. Transgenic overexpression in Xenopus melanotrope cells displaces endogenous p24 proteins, blocks transport of the prohormone POMC, and causes prohormone accumulation in ER-localized electron-dense structures, establishing a non-redundant role in ER-to-Golgi cargo trafficking distinct from other p24 subfamily and intra-subfamily members [#1, #2, #3]. Consistent with a constitutive role in early secretory compartments, TMED4 marks Golgi identity in differentiating male germ cells and remains associated with the migrating Golgi during spermatogenesis [#4]. Beyond trafficking, TMED4 sustains regulatory T cell function: it maintains Foxp3 stability and suppressive activity by limiting ROS accumulation, acting through stabilization of IRE1\\u03b1 — TMED4 suppresses IRE1\\u03b1 proteasomal degradation via BIP-dependent ERAD — and thereby enabling IRE1\\u03b1/XBP1-dependent ER stress signaling and the NRF2 antioxidant response [#0].\",\n  \"teleology\": [\n    {\n      \"year\": 2007,\n      \"claim\": \"Whether p24alpha3 has a dedicated role in secretory cargo transport, as opposed to being a redundant p24 family member, was unresolved; this established it as a specific factor required for ER-to-Golgi prohormone transport.\",\n      \"evidence\": \"Melanotrope-specific transgenic overexpression in Xenopus with electron microscopy and pulse-chase POMC transport assays\",\n      \"pmids\": [\"17684551\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of cargo selection by p24alpha3 not defined\", \"Findings rest on overexpression/displacement rather than loss of function\", \"Human TMED4 not directly assayed\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"It was unclear whether individual p24 members provided distinct versus overlapping secretory functions; comparative transgenics showed p24alpha3 affects cargo cleavage without altering Golgi glycosylation/sulfation, indicating each member shapes a distinct ER/Golgi microenvironment.\",\n      \"evidence\": \"Comparative transgenic expression of multiple p24 subfamily members in Xenopus melanotropes with POMC biosynthesis readouts\",\n      \"pmids\": [\"18699773\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Biochemical basis of the distinct microenvironment unknown\", \"Single lab and single cargo (POMC)\", \"No direct partner mapping among p24 members\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Whether functional distinctions extended within the same p24 subfamily was open; this confirmed intra-subfamily non-redundancy of p24alpha3 relative to p24gamma2 and p24delta1 across transport, cleavage, glycosylation and sulfation.\",\n      \"evidence\": \"Xenopus melanotrope transgenic expression with POMC transport, cleavage, glycosylation, and sulfation assays\",\n      \"pmids\": [\"21118709\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural determinants of subfamily-specific function not identified\", \"Overexpression-based inference\", \"Not tested in mammalian cells\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"The subcellular behavior of TMED4 in a specialized differentiating cell type was unknown; localization showed it stably marks Golgi identity during spermatid differentiation unlike other Golgi proteins lost to the acrosome.\",\n      \"evidence\": \"Golgi fractionation with mass spectrometry and in situ immunolocalization across spermatid differentiation stages\",\n      \"pmids\": [\"25808494\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No functional manipulation of TMED4 in germ cells\", \"Role in acrosome biogenesis not tested\", \"Mechanism of Golgi retention unclear\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Whether TMED4 had functions beyond canonical trafficking was unknown; Treg-specific knockout revealed it sustains IRE1\\u03b1 levels via BIP-dependent ERAD suppression, driving IRE1\\u03b1/XBP1 ER-stress and NRF2 antioxidant responses to limit ROS and preserve Foxp3 stability and Treg suppression.\",\n      \"evidence\": \"Treg-specific conditional knockout mice, ROS measurements, rescue with ROS scavenger/NRF2 inducer/forced IRE1\\u03b1, and co-IP with BIP and IRE1\\u03b1\",\n      \"pmids\": [\"39480507\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How TMED4 mechanistically blocks IRE1\\u03b1 ERAD is not resolved\", \"Direct binding versus indirect stabilization of IRE1\\u03b1 not distinguished\", \"Link between trafficking role and IRE1\\u03b1 stabilization unestablished\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unknown how TMED4's role in ER-to-Golgi cargo transport mechanistically connects to its stabilization of IRE1\\u03b1 and control of ER stress/antioxidant signaling.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No unified molecular model linking trafficking and IRE1\\u03b1 stabilization\", \"Human TMED4 substrate repertoire uncharacterized\", \"Structural basis of p24alpha3 specificity unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0038024\", \"supporting_discovery_ids\": [1, 2, 3]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [4]},\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [1, 0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [1, 2, 3]},\n      {\"term_id\": \"R-HSA-8953897\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"IRE1A\", \"HSPA5\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":4,"faith_total":4,"faith_pct":100.0}}