{"gene":"MARCHF1","run_date":"2026-04-28T18:30:28","timeline":{"discoveries":[{"year":2008,"finding":"MARCH1 (RING-CH ubiquitin E3 ligase) promotes ubiquitination of the HLA-DR beta-chain, inducing surface internalization of mature HLA-DR complexes in non-activated human monocyte-derived dendritic cells, thereby reducing their stability and surface levels. Maturation-dependent down-regulation of MARCH1 is a key event in MHC class II up-regulation at the surface of LPS-activated DCs.","method":"Co-immunoprecipitation, ubiquitination assays, siRNA knockdown, flow cytometry in primary human DCs","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 — reciprocal Co-IP, functional knockdown with defined phenotype, replicated across labs","pmids":["18305173"],"is_preprint":false},{"year":2008,"finding":"IL-10 strongly induces MARCH1 mRNA expression in human primary monocytes, leading to mono- and poly-ubiquitination of MHC class II molecules and their intracellular sequestration. Direct interaction between MHC-II and MARCH1 was demonstrated, and siRNA-mediated knockdown of MARCH1 reverses IL-10-induced MHC-II down-regulation.","method":"Co-immunoprecipitation, siRNA knockdown, ubiquitination assays, flow cytometry in primary human monocytes","journal":"European journal of immunology","confidence":"High","confidence_rationale":"Tier 2 — direct Co-IP, siRNA rescue, replicated by multiple labs","pmids":["18389477"],"is_preprint":false},{"year":2009,"finding":"MARCH1 expression is regulated at the posttranscriptional level with a half-life <30 min. Degradation occurs partly in lysosomes via cysteine proteases. Discrete domains in the N- and C-terminal cytoplasmic tails are required for destabilization, proper localization, and functional interaction with substrates (MHC-II and CD86).","method":"Mutational analysis, lysosomal inhibitor treatment, half-life measurements, reporter fusion assays in primary DCs and APC cell lines","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"High","confidence_rationale":"Tier 1-2 — structure-function mutagenesis with multiple orthogonal methods","pmids":["19880452"],"is_preprint":false},{"year":2009,"finding":"MARCH-I-mediated MHC II ubiquitination is necessary for maintenance of conventional dendritic cell (cDC) functions in steady state. MARCH-I-deficient cDCs accumulate MHC-II and B7-2 but exhibit impaired antigen-presenting ability. MHC-II knockin mice whose MHC-II cannot be ubiquitinated show cDC dysfunction similar to MARCH-I KO mice, establishing that MHC-II (not B7-2) ubiquitination drives this effect.","method":"MARCH-I knockout mice, MHC-II ubiquitination knockin mice, in vivo antigen presentation assays, cytokine production assays","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"High","confidence_rationale":"Tier 2 — genetic epistasis with KO and knockin models, multiple functional readouts","pmids":["19917682"],"is_preprint":false},{"year":2011,"finding":"The transmembrane domain of CD83 blocks MHC class II association with MARCH1, thereby opposing MARCH1-dependent ubiquitination and degradation of MHC class II and CD86 in dendritic cells. IL-10-driven, MARCH1-dependent ubiquitination and degradation is antagonized by the CD83 TM domain.","method":"ENU-induced mutagenesis eliminating CD83 TM domain, genetic complementation, flow cytometry, functional T cell assays in mice","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 — genetic loss-of-function with specific domain dissection, multiple orthogonal readouts","pmids":["21220452"],"is_preprint":false},{"year":2012,"finding":"MARCH1 undergoes autoubiquitination via K48-linked polyubiquitin chains and regulates its own expression. MARCH1 homodimerizes and forms heterodimers with other MARCH family members. An inactive MARCH1 mutant (M1WI) has prolonged half-life; coexpression of active MARCH1 decreases M1WI levels, suggesting transubiquitination.","method":"Immunoprecipitation with polyubiquitin chain-specific antibodies, FRET energy transfer, co-immunoprecipitation, half-life measurements in transfected human cell lines","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"Medium","confidence_rationale":"Tier 2 — multiple orthogonal methods in single lab","pmids":["22508929"],"is_preprint":false},{"year":2012,"finding":"MARCH1 cytoplasmic N-terminal tail contains endosomal sorting motifs. The C-terminal domain contains intracellular sorting signals and a functional 221VQNC224 motif that affects spatial organization of cytoplasmic regions and influences MARCH1 trafficking. Mutation of C-terminal tyrosine-based sorting signals reduces incorporation of MARCH1 into exosomes.","method":"Site-directed mutagenesis, reporter molecule fusions, subcellular localization assays, exosome isolation, structure-function analysis","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 1-2 — structure-function mutagenesis in single lab with multiple readouts","pmids":["23264739"],"is_preprint":false},{"year":2013,"finding":"MARCH1-mediated MHC-II ubiquitination in dendritic cells is required for proper production of naturally occurring regulatory T cells (Treg) in the thymus. DCs deficient in MARCH1 or lacking MHC-II ubiquitination fail to generate antigen-specific Treg cells in vivo and in vitro.","method":"MARCH1 KO mice, MHC-II ubiquitination mutant mice, in vivo and in vitro Treg generation assays, antigen presentation assays","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 — genetic KO and knockin epistasis with defined cellular phenotype, replicated","pmids":["23712430"],"is_preprint":false},{"year":2013,"finding":"Tollip competes with MARCH1 for binding to MHC-II molecules and strongly reduces MARCH1 protein levels, thereby antagonizing MARCH1-dependent MHC-II downregulation. Knockdown of Tollip increases HLA-DR expression; truncation of HLA-DR cytoplasmic tails abrogates the effect of Tollip.","method":"Tollip knockdown, MARCH1 co-expression, co-immunoprecipitation, flow cytometry in CIITA+ HeLa cells","journal":"Results in immunology","confidence":"Medium","confidence_rationale":"Tier 3 — single lab, Co-IP plus functional knockdown","pmids":["24600555"],"is_preprint":false},{"year":2015,"finding":"March-I ubiquitination of pMHC-II promotes degradation of newly synthesized pMHC-II in dendritic cells and prevents recycling of internalized pMHC-II from the cell surface back to the plasma membrane, instead targeting it to lysosomes. Acute APC activation terminates March-I expression, enabling efficient pMHC-II recycling and preventing lysosomal targeting.","method":"MHC-II ubiquitination mutant mice, biochemical recycling assays, lysosomal targeting assays, functional antigen presentation assays in DCs and B cells","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1-2 — reconstitution in primary cells with ubiquitination mutant KI mice plus multiple biochemical assays","pmids":["26240324"],"is_preprint":false},{"year":2015,"finding":"IL-10 stimulates expression of March-I in activated macrophages, thereby down-regulating MHC-II, CD86, and antigen presentation to CD4 T cells. By contrast, IL-10 does not stimulate March-I expression in dendritic cells and does not suppress MHC-II or CD86 on DCs, establishing a cell-type-specific mechanism of IL-10-mediated immunosuppression.","method":"MARCH-I KO macrophages and DCs, flow cytometry, antigen presentation assays, IL-10 stimulation in primary cells","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — KO cells with multiple orthogonal functional readouts, replicated findings","pmids":["26408197"],"is_preprint":false},{"year":2016,"finding":"MARCH1 impairs cellular insulin action by ubiquitinating the insulin receptor (INSR) to decrease cell surface INSR levels in the basal state (before insulin stimulation). March1 loss-of-function enhances, and March1 overexpression impairs, hepatic insulin sensitivity in mice.","method":"Large-scale RNAi screen, March1 KO mice, March1 overexpression mouse model, INSR ubiquitination assays, insulin signaling assays","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 — RNAi screen plus KO and OE mouse models with defined biochemical and physiological phenotypes","pmids":["27577745"],"is_preprint":false},{"year":2018,"finding":"March-I is ubiquitinated on non-lysine residues (lysine-independent ubiquitination) by an unidentified E3 ligase together with the ubiquitin-conjugating enzyme Ube2D1. March-I E3 ligase activity is not required for its own ubiquitination. Knockdown of Ube2D1 impairs March-I ubiquitination and increases March-I expression, enhancing March-I-dependent MHC-II downregulation.","method":"Lysine-less March-I variant expression, Ube2D1 knockdown, ubiquitination assays, western blot in transfected cells","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 — mutagenesis plus siRNA knockdown with biochemical readouts in single lab","pmids":["29414787"],"is_preprint":false},{"year":2018,"finding":"MARCH1-mediated ubiquitination of MHC-II indirectly regulates MHC-I surface expression in B cells and dendritic cells. Absence of MARCH1 reduces surface MHC-I expression not by direct MARCH1 ubiquitination of MHC-I but through altered MHC-II trafficking, establishing an intersection between MHC-I and MHC-II pathways.","method":"MARCH1 KO mice, MHC-II KO in March1-/- cells, MHC-II ubiquitination mutant replacement, flow cytometry, CD8 T cell antigen presentation assays","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 2 — epistasis with multiple KO and knockin combinations, functional antigen presentation readout","pmids":["30001419"],"is_preprint":false},{"year":2018,"finding":"MARCH1 ubiquitin-dependent turnover of MHC-II is critical for maintaining homeostasis of lipid rafts and the tetraspanin web in dendritic cells. Lack of MHC-II ubiquitination causes accumulation of excessive MHC-II in the plasma membrane, disrupting lipid rafts and tetraspanin web, and impairing DC engagement of thymocytes for Treg differentiation.","method":"MARCH1 KO mice, MHC-II ubiquitination mutant mice, lipid raft fractionation, tetraspanin web analysis, thymic Treg differentiation assays","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 — multiple KO/KI models with biochemical membrane domain analysis and functional cellular assays","pmids":["29371232"],"is_preprint":false},{"year":2018,"finding":"Both DCs and B cells possess a distinct isoform of March-I whose expression is regulated by a promoter located within the March-I gene. A core APC-specific promoter drives March-I expression in DCs and B cells but not fibroblasts; downstream regulatory elements in the first coding exon confer activation-induced down-regulation in APCs.","method":"March-I promoter-GFP reporter assays, promoter truncation analysis, activated DCs and B cells","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 — reporter assays with systematic promoter dissection in single lab","pmids":["29378848"],"is_preprint":false},{"year":2020,"finding":"March1 inhibits MAVS/STING/TRIF-induced type I interferon signaling in vitro and in vivo. In malaria-infected hosts, March1 deficiency reduces IFN-I production by activating inhibitors SOCS1, USP18, and TRIM24 and altering immune cell populations, revealing a role in innate immune signaling beyond antigen presentation.","method":"March1 KO mice, Plasmodium yoelii infection model, type I IFN signaling assays, in vitro MAVS/STING/TRIF stimulation","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 — KO mouse model with in vitro and in vivo signaling assays, single lab","pmids":["32606244"],"is_preprint":false},{"year":2020,"finding":"MARCH1 ubiquitination-deficient DCs are poor stimulators of naive CD4 T cells and secrete IL-12 in response to LPS poorly, despite high surface pMHC-II. These functional and gene transcription defects are cell-intrinsic and are reversed by LPS activation. Single-cell RNA sequencing demonstrates that these DCs have an altered gene expression signature.","method":"MHC-II ubiquitination-mutant mouse DCs, naive CD4 T cell stimulation assays, scRNA-seq, IL-12 secretion assays","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"High","confidence_rationale":"Tier 2 — KI mouse model with scRNA-seq and multiple functional assays","pmids":["33318291"],"is_preprint":false},{"year":2021,"finding":"MARCH1 regulates MHC-II and CD86 specifically in professional and atypical antigen-presenting cells of hematopoietic origin (including neutrophils, eosinophils, monocytes) but not in non-hematopoietic cells, where MARCH8 operates. Unbiased proteomic profiling of the plasma membrane established CD86 and MHC-II as the primary in vivo substrates of MARCH1.","method":"MARCH1 and MARCH8 KO mice, unbiased plasma membrane proteomic profiling of primary immune cells","journal":"Current research in immunology","confidence":"High","confidence_rationale":"Tier 1-2 — unbiased proteomics on primary cells from KO mice, definitive substrate identification","pmids":["35492398"],"is_preprint":false},{"year":2021,"finding":"DC induction of TH2 cells depends on MARCH1 ubiquitin ligase in lymph node-resident DCs. The pro-TH2 effect requires ubiquitin acceptor sites of both MHC-II and CD86 (the two MARCH1 substrates), and depends on TCR signaling and GATA-3 induction from naive CD4 T cells by LN-resident (not migratory) DCs.","method":"MARCH1 KO mice, MHC-II and CD86 ubiquitin-acceptor site mutant mice, TH2 differentiation assays, DC subset depletion, GATA-3 expression analysis","journal":"Science immunology","confidence":"High","confidence_rationale":"Tier 2 — multiple KO and KI models with epistatic analysis and functional T cell differentiation readouts","pmids":["34652961"],"is_preprint":false},{"year":2021,"finding":"MARCH1 promotes OX40L expression in allergen-stimulated dendritic cells by ubiquitinating and degrading HDAC11. HDAC11 normally combines with KLF4 to decrease OX40L promoter activity; MARCH1-driven HDAC11 degradation thus de-represses OX40L expression.","method":"Co-immunoprecipitation, ubiquitination assays, luciferase promoter assays, immunofluorescence co-localization, Western blot in DCs from asthmatic patients and animal models","journal":"Journal of asthma and allergy","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus ubiquitination assay plus functional promoter assay in single lab","pmids":["34385821"],"is_preprint":false},{"year":2021,"finding":"MARCH1 recognizes CD86 through a specific surface in the hydrophobic core of the CD86 transmembrane domain, prominently featuring a proline at position 254, distinct from the recognition mode of viral KSHV MIR2 which requires an aspartic acid in the extracellular juxtamembrane region. This defines the MARCH1 substrate recognition mechanism for CD86.","method":"Deep mutational scanning of CD86 transmembrane domain, functional downregulation assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — systematic deep mutational scanning defining recognition surface at residue resolution","pmids":["34157285"],"is_preprint":false},{"year":2022,"finding":"MARCH1 isoform 1 (MARCH1.1) restricts influenza A virus (IAV) replication whereas isoform 2 (MARCH1.2) does not. The 16 N-terminal residues of MARCH1.2's cytoplasmic domain suppress IAV restriction activity, as deletion of these residues restores IAV inhibition.","method":"Doxycycline-inducible MARCH1 isoform overexpression, viral titer assays, sequential N-terminal deletion mapping","journal":"Viruses","confidence":"Medium","confidence_rationale":"Tier 2 — domain mapping with functional virus replication assays in single lab","pmids":["36423158"],"is_preprint":false},{"year":2022,"finding":"MARCH1 mediates ubiquitination and degradation of the transferrin receptor (TfR) during HCMV infection, regulating cellular iron levels and the labile iron pool. MARCH1 knockdown leads to decreased infectious viral titers and increased ROS, lipid peroxidation, and mitochondrial dysfunction.","method":"MARCH1 knockdown, TfR expression analysis, labile iron pool measurement, viral titer assays, ROS and lipid peroxidation assays during HCMV infection","journal":"Journal of virology","confidence":"Medium","confidence_rationale":"Tier 2-3 — knockdown with multiple functional readouts in single lab","pmids":["35045264"],"is_preprint":false},{"year":2023,"finding":"MARCHF1 acts as a novel E3 ligase for GPX4, promoting its ubiquitination and degradation, thereby inducing ferroptosis. BaP/BPDE exposure upregulates MARCHF1 to promote GPX4 degradation in endothelial cells.","method":"MARCHF1 overexpression/knockdown, GPX4 ubiquitination assay, ferroptosis assays in HUVECs and mouse miscarriage model","journal":"Environment international","confidence":"Medium","confidence_rationale":"Tier 2-3 — ubiquitination assay plus cellular functional readout in single lab","pmids":["37802009"],"is_preprint":false},{"year":2024,"finding":"MARCH1 and MARCH2 retain Ebola virus glycoprotein (GP) at the trans-Golgi network by interacting with the furin P domain, blocking furin cleavage of EBOV GP and impairing pseudotyped virus infectivity.","method":"MARCH1/2 overexpression, EBOV GP-pseudotyped virus infectivity assays, furin co-immunoprecipitation, subcellular localization analysis","journal":"Journal of medical virology","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus functional virus assay plus subcellular localization in single lab","pmids":["38299743"],"is_preprint":false},{"year":2024,"finding":"MARCH1 interacts with TBK1 and promotes K63-linked ubiquitination of TBK1, which attenuates TBK1 interaction with mTOR and thereby inhibits growth factor-induced mTOR signaling. MARCH1 also interacts with STING. MARCH1 deficiency-induced faster proliferation is reversed by mTOR, STING, or TBK1 inhibition.","method":"Co-immunoprecipitation, denatured Co-IP for ubiquitination, MARCH1 overexpression/knockdown, mTOR signaling assays, clonogenic and wound healing assays","journal":"BMC cancer","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus ubiquitination assay plus epistasis via inhibitors in single lab","pmids":["39061024"],"is_preprint":false},{"year":2024,"finding":"MARCH1 mediates ubiquitination and degradation of PCSK9 in brain neurons under ischemic conditions. MARCH1-mediated PCSK9 downregulation reduces brain damage by inhibiting NLRP3 inflammasome activation and pyroptosis, and by upregulating LDLR.","method":"Cycloheximide assay, co-immunoprecipitation, MARCH1/PCSK9 ectopic expression and knockdown, MCAO/R mouse model and OGD/R neuronal model","journal":"Mammalian genome","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus ubiquitination assay plus in vivo/in vitro models in single lab","pmids":["39115562"],"is_preprint":false},{"year":2025,"finding":"MARCH1 interacts with GABAB receptors specifically under ischemic/excitotoxic conditions and downregulates plasma membrane GABAB receptor levels by inhibiting fast receptor recycling. An interfering peptide blocking the MARCH1/GABAB interaction restored receptor expression and prevented progressive neuronal death.","method":"Co-immunoprecipitation, MARCH1 upregulation assays under ischemia, plasma membrane receptor quantification, interfering peptide treatment, neuronal viability assays","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus functional rescue with interfering peptide, single lab","pmids":["39779794"],"is_preprint":false},{"year":2025,"finding":"MARCHF1 interacts with and promotes ubiquitination and degradation of PHLPP2 in oral squamous cell carcinoma cells, enhancing cell proliferation and suppressing apoptosis.","method":"Co-immunoprecipitation, ubiquitination assay, MARCH1 knockdown/overexpression, proliferation and apoptosis assays, in vivo tumor grafting","journal":"Clinical & translational oncology","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus ubiquitination assay plus in vivo model in single lab","pmids":["35122633"],"is_preprint":false},{"year":2025,"finding":"CD83 suppresses endogenous March-I-dependent MHC-II ubiquitination, endocytosis, and degradation in mouse spleen DCs. Endogenous March-I protein is expressed at very low levels (~500 molecules/cell in DCs) with a very short half-life; March-I mRNA, protein, and MHC-II ubiquitination are rapidly terminated upon DC or B cell activation.","method":"V5 epitope knock-in to endogenous March-I gene, quantitative flow cytometry, March-I half-life measurement, activated DC/B cell functional assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1-2 — endogenous protein tagging plus quantitative biochemical analysis with functional validation","pmids":["40397676"],"is_preprint":false},{"year":2025,"finding":"MARCHF1 interacts with REST (repressor element-1 silencing transcription factor) and promotes its ubiquitination and degradation, thereby de-repressing transcription of mitochondrial transcription factor TFAM, supporting mitochondrial function and breast cancer cell proliferation.","method":"Co-immunoprecipitation, ubiquitination assay, MARCHF1 knockdown/overexpression, TFAM mRNA analysis, mitochondrial function assays, in vivo tumor model","journal":"Cell biology international","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus ubiquitination assay plus functional pathway analysis in single lab","pmids":["39428668"],"is_preprint":false},{"year":2025,"finding":"MARCHF1 interacts with and promotes ubiquitination-mediated degradation of MYCT1, a candidate tumor suppressor, facilitating AML cell proliferation and inhibiting apoptosis and differentiation. POU2F2 transcription factor positively regulates MARCH1 transcription in AML.","method":"Co-immunoprecipitation, ubiquitination assay, MARCH1 knockdown/overexpression, MARCH1 promoter analysis, AML mouse in vivo model","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2-3 — Co-IP plus ubiquitination assay plus in vivo model in single lab","pmids":["40533483"],"is_preprint":false},{"year":2025,"finding":"SARS-CoV-2 M protein interacts with GPX4 (at R72 residue) and promotes its degradation via MARCHF1 E3 ubiquitin ligase, leading to ferroptosis through the MARCHF1-GPX4 axis.","method":"Co-immunoprecipitation, GPX4-M interaction mapping (R72 mutation), MARCHF1-dependent ubiquitination assay, ferroptosis assays","journal":"Journal of medical virology","confidence":"Medium","confidence_rationale":"Tier 2-3 — interaction mapping with mutagenesis plus ubiquitination assay in single lab","pmids":["40186530"],"is_preprint":false},{"year":2023,"finding":"MARCH1 restricts HIV infectivity in macrophages by limiting incorporation of HIV envelope glycoproteins into nascent virions. HIV-1 Vpu counteracts this restriction by inducing microRNAs-25 and -93 that downregulate MARCH1 mRNA, via hijacking the cellular β-catenin pathway.","method":"miRNA-25/93 induction assays, MARCH1 mRNA knockdown, viral infectivity assays, β-catenin pathway analysis in macrophages","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2-3 — functional viral assay plus mechanistic pathway dissection in single lab","pmids":["37773002"],"is_preprint":false}],"current_model":"MARCHF1 is a membrane-bound RING-CH E3 ubiquitin ligase that constitutively ubiquitinates MHC class II (at the beta-chain) and CD86 in antigen-presenting cells to promote their endocytosis, lysosomal degradation, and intracellular sequestration, thereby suppressing antigen presentation in resting DCs and monocytes; upon DC maturation or activation, MARCH1 expression is terminated (transcriptionally and post-translationally via Ube2D1-dependent lysine-independent self-ubiquitination and lysosomal proteolysis), stabilizing surface pMHC-II for effective CD4 T cell activation, while additional substrates including the insulin receptor, INSR, GPX4, TfR, PCSK9, TBK1, GABAB receptors, PHLPP2, HDAC11, REST, MYCT1, and SLC25A17 extend its regulatory roles to insulin signaling, ferroptosis, innate immune signaling, iron metabolism, and cancer cell biology."},"narrative":{"teleology":[{"year":2008,"claim":"The identity of the E3 ligase responsible for MHC-II turnover in resting DCs was unknown; two independent studies established that MARCHF1 ubiquitinates MHC-II β-chain to drive its internalization, and that IL-10 induces MARCHF1 to downregulate MHC-II in monocytes, defining MARCHF1 as the key MHC-II ubiquitin ligase in professional APCs.","evidence":"Co-immunoprecipitation, ubiquitination assays, and siRNA knockdown in primary human DCs and monocytes","pmids":["18305173","18389477"],"confidence":"High","gaps":["Structural basis of MARCHF1–MHC-II interaction not defined","E2 enzyme(s) partnering with MARCHF1 for MHC-II ubiquitination not identified"]},{"year":2009,"claim":"Whether MARCHF1-mediated MHC-II ubiquitination was physiologically required in vivo was untested; MARCH-I knockout and MHC-II ubiquitination-site knockin mice demonstrated that MARCHF1-dependent MHC-II ubiquitination is essential for steady-state cDC function, while structure-function analysis revealed the protein's extremely short half-life and lysosomal degradation.","evidence":"MARCH-I KO mice, MHC-II ubiquitin-acceptor KI mice, antigen presentation assays, lysosomal inhibitor studies, domain mutagenesis","pmids":["19917682","19880452"],"confidence":"High","gaps":["Mechanism of activation-induced MARCHF1 transcriptional silencing not resolved","Contribution of individual cytoplasmic tail domains to in vivo function unclear"]},{"year":2011,"claim":"How surface MHC-II is protected from MARCHF1 during DC maturation was unknown; CD83's transmembrane domain was shown to block MARCHF1–MHC-II association, providing a mechanistic counterbalance to MARCHF1 activity.","evidence":"ENU mutagenesis eliminating CD83 TM domain, genetic complementation, T cell functional assays in mice","pmids":["21220452"],"confidence":"High","gaps":["Direct CD83 TM–MARCHF1 TM interaction interface not structurally resolved","Whether CD83 also protects CD86 from MARCHF1 independently of MHC-II not tested"]},{"year":2012,"claim":"MARCHF1 self-regulation was poorly understood; autoubiquitination via K48-linked chains, homodimerization, and trans-ubiquitination of inactive partners were demonstrated, along with identification of cytoplasmic sorting motifs directing MARCHF1 trafficking including exosome incorporation.","evidence":"FRET, Co-IP with chain-specific antibodies, half-life measurements, site-directed mutagenesis and exosome isolation","pmids":["22508929","23264739"],"confidence":"Medium","gaps":["Physiological role of MARCHF1 in exosomes not established","Whether homodimerization is required for substrate ubiquitination unknown"]},{"year":2013,"claim":"The immunological consequence of MARCHF1-mediated MHC-II ubiquitination for T cell tolerance was unknown; MARCHF1-dependent MHC-II ubiquitination proved essential for thymic regulatory T cell generation, and Tollip was identified as a competitive antagonist of MARCHF1 binding to MHC-II.","evidence":"MARCH1 KO and MHC-II ubiquitination mutant mice with in vivo Treg assays; Tollip knockdown and Co-IP in CIITA+ HeLa cells","pmids":["23712430","24600555"],"confidence":"High","gaps":["Mechanism by which Tollip reduces MARCHF1 protein levels not clarified","Whether Tollip–MARCHF1 competition occurs in primary DCs in vivo not confirmed"]},{"year":2015,"claim":"How MARCHF1 controls the fate of internalized pMHC-II was unclear; MARCHF1-dependent ubiquitination was shown to redirect internalized pMHC-II from recycling to lysosomal degradation, and IL-10-induced MARCHF1 expression was found to be cell-type specific—operating in macrophages but not DCs.","evidence":"MHC-II ubiquitination mutant mice, biochemical recycling/lysosomal targeting assays, MARCH-I KO macrophages and DCs with antigen presentation readouts","pmids":["26240324","26408197"],"confidence":"High","gaps":["Sorting adaptors linking ubiquitinated MHC-II to lysosomal targeting not identified","Whether other cytokines besides IL-10 regulate MARCHF1 in macrophages not systematically examined"]},{"year":2016,"claim":"MARCHF1 substrate range beyond immune molecules was unexplored; an RNAi screen and mouse models revealed that MARCHF1 ubiquitinates the insulin receptor to control surface INSR levels and hepatic insulin sensitivity, establishing a metabolic role.","evidence":"Large-scale RNAi screen, March1 KO and overexpression mice, INSR ubiquitination and insulin signaling assays","pmids":["27577745"],"confidence":"High","gaps":["Whether MARCHF1-INSR interaction occurs in tissues other than liver not tested","MARCHF1 recognition determinants on the INSR not mapped"]},{"year":2018,"claim":"Multiple mechanistic facets were clarified: MARCHF1 itself undergoes lysine-independent ubiquitination via Ube2D1; MARCHF1-dependent MHC-II ubiquitination indirectly modulates MHC-I surface expression; MARCHF1 controls lipid raft and tetraspanin web homeostasis; and an APC-specific promoter with activation-responsive elements was defined.","evidence":"Ube2D1 knockdown and lysine-less MARCHF1 mutants; MARCH1/MHC-II double-KO epistasis; lipid raft fractionation in KO/KI mice; promoter-GFP reporter truncation assays","pmids":["29414787","30001419","29371232","29378848"],"confidence":"High","gaps":["The E3 ligase mediating MARCHF1's own lysine-independent ubiquitination not identified","Structural basis for MHC-II ubiquitination effects on lipid rafts not elucidated"]},{"year":2020,"claim":"Whether MARCHF1 functions beyond antigen presentation in innate immunity was unknown; MARCHF1 was shown to modulate MAVS/STING/TRIF-induced type I interferon production, and MARCHF1-deficient DCs exhibited intrinsic transcriptional and functional defects despite high surface pMHC-II.","evidence":"March1 KO mice with Plasmodium infection, IFN-I signaling assays; MHC-II ubiquitination-mutant DCs with scRNA-seq and T cell stimulation","pmids":["32606244","33318291"],"confidence":"Medium","gaps":["Direct substrates mediating MARCHF1's effect on IFN-I signaling not identified at this stage","Causal link between altered DC transcriptome and poor T cell stimulation not resolved"]},{"year":2021,"claim":"Multiple advances defined substrate specificity and physiological impact: deep mutational scanning revealed that MARCHF1 recognizes CD86 via a proline-centered hydrophobic surface in its transmembrane domain; unbiased proteomics confirmed MHC-II and CD86 as primary in vivo substrates restricted to hematopoietic APCs; MARCHF1-dependent ubiquitination of both substrates was required for TH2 polarization by lymph node DCs; and HDAC11 was identified as a substrate linking MARCHF1 to OX40L de-repression in allergic DCs.","evidence":"Deep mutational scanning of CD86 TM; plasma membrane proteomics from MARCH1/MARCH8 KO mice; MHC-II/CD86 ubiquitin-acceptor mutant mice with TH2 assays; HDAC11 Co-IP and promoter assays in asthmatic DCs","pmids":["34157285","35492398","34652961","34385821"],"confidence":"High","gaps":["Whether MARCHF1 TM domain directly contacts CD86 TM domain awaits structural confirmation","HDAC11 as MARCHF1 substrate reported by single lab only"]},{"year":2022,"claim":"MARCHF1's antiviral functions were expanded: isoform-specific restriction of influenza A virus was mapped to N-terminal cytoplasmic residues, and MARCHF1 was found to ubiquitinate the transferrin receptor during HCMV infection to regulate iron homeostasis and viral replication.","evidence":"Doxycycline-inducible isoform expression with IAV titer assays; TfR expression/iron assays during HCMV infection with MARCHF1 knockdown","pmids":["36423158","35045264"],"confidence":"Medium","gaps":["Direct ubiquitination of TfR by MARCHF1 not shown with purified components","Whether IAV restriction involves a defined MARCHF1 substrate unclear"]},{"year":2023,"claim":"MARCHF1 was established as an E3 ligase for GPX4, linking it to ferroptosis regulation, and was shown to restrict HIV infectivity in macrophages by limiting envelope glycoprotein incorporation into virions—a restriction counteracted by HIV Vpu via miR-25/93-mediated MARCHF1 downregulation.","evidence":"GPX4 ubiquitination assays and ferroptosis readouts in HUVECs; miRNA induction assays, MARCHF1 mRNA knockdown, viral infectivity assays in macrophages","pmids":["37802009","37773002"],"confidence":"Medium","gaps":["GPX4 as direct MARCHF1 substrate confirmed in a single lab","Whether MARCHF1 restricts HIV by ubiquitinating envelope glycoproteins directly not demonstrated"]},{"year":2024,"claim":"MARCHF1's substrate repertoire expanded to signaling and metabolic regulators: K63-linked ubiquitination of TBK1 attenuates mTOR signaling; ubiquitination-dependent degradation of PCSK9 in neurons protects against ischemic brain injury; MARCHF1 interaction with GABAB receptors under ischemia blocks receptor recycling; and MARCHF1 retains Ebola virus GP at the trans-Golgi via furin interaction.","evidence":"Co-IP and ubiquitination assays for TBK1, PCSK9, and GABAB receptors; MCAO/R mouse model; interfering peptide rescue; EBOV-pseudovirus infectivity and furin Co-IP","pmids":["39061024","39115562","39779794","38299743"],"confidence":"Medium","gaps":["Each new substrate reported by a single laboratory; independent replication needed","Whether TBK1 K63-ubiquitination by MARCHF1 requires a specific E2 enzyme unknown","Physiological relevance of MARCHF1-GABAB interaction outside ischemia not addressed"]},{"year":2025,"claim":"Endogenous MARCHF1 protein was quantified for the first time (~500 molecules/DC) using a V5 knock-in, confirming CD83 as an endogenous antagonist; additional cancer-relevant substrates PHLPP2, REST, and MYCT1 were identified, and SARS-CoV-2 M protein was shown to hijack MARCHF1-dependent GPX4 degradation to induce ferroptosis.","evidence":"V5 epitope knock-in to endogenous locus with quantitative flow cytometry; Co-IP/ubiquitination assays and in vivo tumor models for PHLPP2/REST/MYCT1; M protein–GPX4 interaction mapping with MARCHF1-dependent ubiquitination assays","pmids":["40397676","35122633","39428668","40533483","40186530"],"confidence":"High","gaps":["Cancer-related substrates each reported by single labs; validation in independent systems pending","Structural basis for MARCHF1 substrate selectivity across diverse transmembrane and soluble proteins remains unknown"]},{"year":null,"claim":"No high-resolution structure of MARCHF1 exists, and the mechanism by which a single RING-CH E3 ligase recognizes such a diverse set of transmembrane and cytoplasmic substrates (MHC-II, CD86, INSR, GPX4, TBK1, TfR, PCSK9, GABAB receptor, PHLPP2, REST, MYCT1, HDAC11) remains unresolved. The E3 ligase that mediates MARCHF1's own lysine-independent ubiquitination has not been identified.","evidence":"","pmids":[],"confidence":"High","gaps":["No crystal or cryo-EM structure of MARCHF1 or any MARCHF1–substrate complex","E3 ligase targeting MARCHF1 for degradation not identified","Systematic comparison of MARCHF1 vs MARCH8 substrate selectivity determinants lacking"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,1,3,5,9,11,13,14,18,19,20,21,23,24,26,27,29,31,32,33]},{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[0,1,5,11,24,26]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,1,11,18,21,28]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[2,6,9]},{"term_id":"GO:0005764","term_label":"lysosome","supporting_discovery_ids":[2,9]},{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[25]}],"pathway":[{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[0,1,3,4,7,9,10,13,14,17,18,19]},{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,1,5,11,12,24,26,29,31,32]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[11,16,26,27]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[24,33]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[6,9,25]}],"complexes":[],"partners":["HLA-DRB1","CD86","INSR","CD83","GPX4","TBK1","TFRC","PCSK9"],"other_free_text":[]},"mechanistic_narrative":"MARCHF1 is a membrane-associated RING-CH E3 ubiquitin ligase that serves as a master regulator of surface receptor turnover in antigen-presenting cells, controlling adaptive immune priming, T helper cell polarization, and thymic regulatory T cell generation. In resting dendritic cells, B cells, and monocytes, MARCHF1 constitutively ubiquitinates the MHC class II β-chain and CD86 costimulatory molecule, driving their endocytosis and lysosomal degradation; upon APC activation or maturation, MARCHF1 expression is rapidly extinguished at both transcriptional and post-translational levels (the protein has a half-life under 30 minutes and is expressed at ~500 molecules per DC), thereby stabilizing surface pMHC-II–CD86 complexes for productive CD4 T cell stimulation [PMID:18305173, PMID:19880452, PMID:40397676]. Unbiased plasma membrane proteomics confirms MHC-II and CD86 as the primary physiological substrates in hematopoietic APCs, and MARCHF1-dependent MHC-II ubiquitination maintains lipid raft and tetraspanin web homeostasis essential for Treg generation and TH2 polarization [PMID:35492398, PMID:29371232, PMID:34652961]. Beyond immune regulation, MARCHF1 ubiquitinates the insulin receptor to modulate hepatic insulin sensitivity, promotes ferroptosis by targeting GPX4 for degradation, regulates TBK1 via K63-linked ubiquitination to attenuate mTOR signaling, and restricts replication of influenza A virus and HIV by limiting viral glycoprotein availability [PMID:27577745, PMID:37802009, PMID:39061024, PMID:36423158, PMID:37773002]."},"prefetch_data":{"uniprot":{"accession":"Q8TCQ1","full_name":"E3 ubiquitin-protein ligase MARCHF1","aliases":["Membrane-associated RING finger protein 1","Membrane-associated RING-CH protein I","MARCH-I","RING finger protein 171","RING-type E3 ubiquitin transferase MARCHF1"],"length_aa":289,"mass_kda":32.3,"function":"E3 ubiquitin-protein ligase that mediates ubiquitination of TFRC, CD86, FAS and MHC class II proteins, such as HLA-DR alpha and beta, and promotes their subsequent endocytosis and sorting to lysosomes via multivesicular bodies (PubMed:18389477, PubMed:18305173, PubMed:21220452, PubMed:35045264). By constitutively ubiquitinating MHC class II proteins in immature dendritic cells, down-regulates their cell surface localization thus sequestering them in the intracellular endosomal system. Also regulates insulin sensitivity by controlling surface expression of the insulin receptor subunit beta/INSR by direct ubiquitination and degradation (PubMed:27577745) (Microbial infection) Plays a role in iron metabolism by regulating the levels of the transferrin receptor TFRC during human cytomegalovirus infection, subsequently contributing to a proviral effect","subcellular_location":"Golgi apparatus, trans-Golgi network membrane; Lysosome membrane; Cytoplasmic vesicle membrane; Late endosome membrane; Early endosome membrane; Cell membrane","url":"https://www.uniprot.org/uniprotkb/Q8TCQ1/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MARCHF1","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1090,"dependency_fraction":0.0009174311926605505},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/MARCHF1","total_profiled":1310},"omim":[{"mim_id":"613331","title":"MEMBRANE-ASSOCIATED RING-CH FINGER PROTEIN 1; MARCHF1","url":"https://www.omim.org/entry/613331"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Vesicles","reliability":"Supported"},{"location":"Endoplasmic reticulum","reliability":"Additional"},{"location":"Golgi apparatus","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"lymphoid tissue","ntpm":29.3},{"tissue":"retina","ntpm":21.3}],"url":"https://www.proteinatlas.org/search/MARCHF1"},"hgnc":{"alias_symbol":["FLJ20668","MARCH-I","RNF171"],"prev_symbol":["MARCH1"]},"alphafold":{"accession":"Q8TCQ1","domains":[{"cath_id":"3.30.40.10","chopping":"77-131","consensus_level":"medium","plddt":94.1173,"start":77,"end":131},{"cath_id":"1.10.287","chopping":"150-236","consensus_level":"high","plddt":87.122,"start":150,"end":236}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8TCQ1","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8TCQ1-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8TCQ1-F1-predicted_aligned_error_v6.png","plddt_mean":68.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MARCHF1","jax_strain_url":"https://www.jax.org/strain/search?query=MARCHF1"},"sequence":{"accession":"Q8TCQ1","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8TCQ1.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8TCQ1/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8TCQ1"}},"corpus_meta":[{"pmid":"18305173","id":"PMC_18305173","title":"MHC 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Wnt/β-catenin pathways.","date":"2016","source":"Oncology reports","url":"https://pubmed.ncbi.nlm.nih.gov/27633480","citation_count":41,"is_preprint":false},{"pmid":"22508929","id":"PMC_22508929","title":"Autoregulation of MARCH1 expression by dimerization and autoubiquitination.","date":"2012","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/22508929","citation_count":39,"is_preprint":false},{"pmid":"32606244","id":"PMC_32606244","title":"The E3 ubiquitin ligase MARCH1 regulates antimalaria immunity through interferon signaling and T cell activation.","date":"2020","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/32606244","citation_count":38,"is_preprint":false},{"pmid":"30001419","id":"PMC_30001419","title":"MARCH1-mediated ubiquitination of MHC II impacts the MHC I antigen presentation pathway.","date":"2018","source":"PloS 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Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/30678274","citation_count":33,"is_preprint":false},{"pmid":"27940660","id":"PMC_27940660","title":"MARCH1 E3 Ubiquitin Ligase Dampens the Innate Inflammatory Response by Modulating Monocyte Functions in Mice.","date":"2016","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/27940660","citation_count":33,"is_preprint":false},{"pmid":"30154416","id":"PMC_30154416","title":"March1-dependent modulation of donor MHC II on CD103+ dendritic cells mitigates alloimmunity.","date":"2018","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/30154416","citation_count":31,"is_preprint":false},{"pmid":"29414787","id":"PMC_29414787","title":"Ubiquitin-conjugating enzyme E2 D1 (Ube2D1) mediates lysine-independent ubiquitination of the E3 ubiquitin ligase March-I.","date":"2018","source":"The Journal of biological 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network.","date":"2024","source":"Veterinary microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/38936155","citation_count":6,"is_preprint":false},{"pmid":"35985246","id":"PMC_35985246","title":"MARCH1 promotes the growth and maintaining of stem cell-like characteristics of gastric cancer cells by activating the Wnt/β-catenin signaling pathway.","date":"2022","source":"Tissue & cell","url":"https://pubmed.ncbi.nlm.nih.gov/35985246","citation_count":6,"is_preprint":false},{"pmid":"34923421","id":"PMC_34923421","title":"March1-overexpressed dendritic cells downregulate Th1/Th2 ratio in asthma through promoting OX40L.","date":"2021","source":"International immunopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/34923421","citation_count":6,"is_preprint":false},{"pmid":"39061024","id":"PMC_39061024","title":"MARCH1 negatively regulates TBK1-mTOR signaling pathway by ubiquitinating TBK1.","date":"2024","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/39061024","citation_count":4,"is_preprint":false},{"pmid":"32973799","id":"PMC_32973799","title":"Lack of the E3 Ubiquitin Ligase March1 Affects CD8 T Cell Fate and Exacerbates Insulin Resistance in Obese Mice.","date":"2020","source":"Frontiers in immunology","url":"https://pubmed.ncbi.nlm.nih.gov/32973799","citation_count":4,"is_preprint":false},{"pmid":"36100368","id":"PMC_36100368","title":"MARCH1 Controls an Exhaustion-like Program of Effector CD4+ T Cells Promoting Allergic Airway Inflammation.","date":"2022","source":"ImmunoHorizons","url":"https://pubmed.ncbi.nlm.nih.gov/36100368","citation_count":4,"is_preprint":false},{"pmid":"36451862","id":"PMC_36451862","title":"Targeting psychological stress-steroid-MARCH1 signaling pathway promotes the efficacy of specific allergen immunotherapy.","date":"2022","source":"Theranostics","url":"https://pubmed.ncbi.nlm.nih.gov/36451862","citation_count":3,"is_preprint":false},{"pmid":"40186530","id":"PMC_40186530","title":"SARS-CoV-2 Membrane Protein Induces MARCHF1/GPX4-Mediated Ferroptosis by Promoting Lipid Accumulation.","date":"2025","source":"Journal of medical virology","url":"https://pubmed.ncbi.nlm.nih.gov/40186530","citation_count":2,"is_preprint":false},{"pmid":"38331309","id":"PMC_38331309","title":"MARCH-I: A negative regulator of dendritic cell maturation.","date":"2024","source":"Experimental cell research","url":"https://pubmed.ncbi.nlm.nih.gov/38331309","citation_count":2,"is_preprint":false},{"pmid":"34853711","id":"PMC_34853711","title":"A Novel 4q32.3 Deletion in a Child: Additional Signs and the Role of MARCH1.","date":"2021","source":"Journal of pediatric genetics","url":"https://pubmed.ncbi.nlm.nih.gov/34853711","citation_count":2,"is_preprint":false},{"pmid":"39779794","id":"PMC_39779794","title":"The E3 ubiquitin ligase MARCH1 mediates downregulation of plasma membrane GABAB receptors under ischemic conditions by inhibiting fast receptor recycling.","date":"2025","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/39779794","citation_count":2,"is_preprint":false},{"pmid":"40533483","id":"PMC_40533483","title":"MARCH1, transcriptionally regulated by POU2F2, facilitates acute myeloid leukemia progression via inducing MYCT1 degradation.","date":"2025","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/40533483","citation_count":2,"is_preprint":false},{"pmid":"35656075","id":"PMC_35656075","title":"Induced overexpression of MARCH-1 in human macrophages altered to M2 phenotype for suppressing inflammation process.","date":"2022","source":"Iranian journal of basic medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35656075","citation_count":2,"is_preprint":false},{"pmid":"40397676","id":"PMC_40397676","title":"CD83 suppresses endogenous March-I-dependent MHC class II ubiquitination, endocytosis, and degradation.","date":"2025","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/40397676","citation_count":1,"is_preprint":false},{"pmid":"33537243","id":"PMC_33537243","title":"RON Expression Mediates Lipopolysaccharide-Mediated Dendritic Cell Maturation via March-I.","date":"2021","source":"Frontiers in cellular and infection microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/33537243","citation_count":1,"is_preprint":false},{"pmid":"21385572","id":"PMC_21385572","title":"MARCH-I expression in cord blood CD34+KDR+ cells.","date":"2011","source":"Clinical biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21385572","citation_count":1,"is_preprint":false},{"pmid":"39428668","id":"PMC_39428668","title":"MARCHF1 promotes breast cancer through accelerating REST ubiquitylation and following TFAM transcription.","date":"2024","source":"Cell biology international","url":"https://pubmed.ncbi.nlm.nih.gov/39428668","citation_count":0,"is_preprint":false},{"pmid":"41283654","id":"PMC_41283654","title":"HIV-2 glycoproteins upregulate microRNAs 25 and 93 to counter the MARCH1 antiviral effect in macrophages.","date":"2025","source":"Journal of virology","url":"https://pubmed.ncbi.nlm.nih.gov/41283654","citation_count":0,"is_preprint":false},{"pmid":"41550717","id":"PMC_41550717","title":"MARCHF1-mediated SULF1 degradation blocks THBS2/TGF-β/SMAD2/3 signaling to reverse colon cancer metastasis and 5-FU resistance.","date":"2025","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/41550717","citation_count":0,"is_preprint":false},{"pmid":"41758657","id":"PMC_41758657","title":"MARCH1 attenuates lung adenocarcinoma by blocking macrophage M2 polarization and cisplatin resistance through reducing SLC25A17 stability.","date":"2026","source":"Integrative biology : quantitative biosciences from nano to macro","url":"https://pubmed.ncbi.nlm.nih.gov/41758657","citation_count":0,"is_preprint":false},{"pmid":"41986908","id":"PMC_41986908","title":"MARCH1 Deletion Attenuates HFpEF by Promoting Adipose Beiging.","date":"2026","source":"Comprehensive Physiology","url":"https://pubmed.ncbi.nlm.nih.gov/41986908","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.10.25.24316158","title":"Gene-Excessive Sleepiness Interactions Suggest Treatment Targets for Obstructive Sleep Apnea Subtype","date":"2024-10-28","source":"bioRxiv","url":"https://doi.org/10.1101/2024.10.25.24316158","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":35172,"output_tokens":8210,"usd":0.114333},"stage2":{"model":"claude-opus-4-6","input_tokens":11975,"output_tokens":4684,"usd":0.265462},"total_usd":0.379795,"stage1_batch_id":"msgbatch_01Mgbec4vM6c9vXht7JVJzss","stage2_batch_id":"msgbatch_01JkuuH5RB2BdJNsgnhjbC6s","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2008,\n      \"finding\": \"MARCH1 (RING-CH ubiquitin E3 ligase) promotes ubiquitination of the HLA-DR beta-chain, inducing surface internalization of mature HLA-DR complexes in non-activated human monocyte-derived dendritic cells, thereby reducing their stability and surface levels. Maturation-dependent down-regulation of MARCH1 is a key event in MHC class II up-regulation at the surface of LPS-activated DCs.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assays, siRNA knockdown, flow cytometry in primary human DCs\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP, functional knockdown with defined phenotype, replicated across labs\",\n      \"pmids\": [\"18305173\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"IL-10 strongly induces MARCH1 mRNA expression in human primary monocytes, leading to mono- and poly-ubiquitination of MHC class II molecules and their intracellular sequestration. Direct interaction between MHC-II and MARCH1 was demonstrated, and siRNA-mediated knockdown of MARCH1 reverses IL-10-induced MHC-II down-regulation.\",\n      \"method\": \"Co-immunoprecipitation, siRNA knockdown, ubiquitination assays, flow cytometry in primary human monocytes\",\n      \"journal\": \"European journal of immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — direct Co-IP, siRNA rescue, replicated by multiple labs\",\n      \"pmids\": [\"18389477\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"MARCH1 expression is regulated at the posttranscriptional level with a half-life <30 min. Degradation occurs partly in lysosomes via cysteine proteases. Discrete domains in the N- and C-terminal cytoplasmic tails are required for destabilization, proper localization, and functional interaction with substrates (MHC-II and CD86).\",\n      \"method\": \"Mutational analysis, lysosomal inhibitor treatment, half-life measurements, reporter fusion assays in primary DCs and APC cell lines\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — structure-function mutagenesis with multiple orthogonal methods\",\n      \"pmids\": [\"19880452\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"MARCH-I-mediated MHC II ubiquitination is necessary for maintenance of conventional dendritic cell (cDC) functions in steady state. MARCH-I-deficient cDCs accumulate MHC-II and B7-2 but exhibit impaired antigen-presenting ability. MHC-II knockin mice whose MHC-II cannot be ubiquitinated show cDC dysfunction similar to MARCH-I KO mice, establishing that MHC-II (not B7-2) ubiquitination drives this effect.\",\n      \"method\": \"MARCH-I knockout mice, MHC-II ubiquitination knockin mice, in vivo antigen presentation assays, cytokine production assays\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — genetic epistasis with KO and knockin models, multiple functional readouts\",\n      \"pmids\": [\"19917682\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"The transmembrane domain of CD83 blocks MHC class II association with MARCH1, thereby opposing MARCH1-dependent ubiquitination and degradation of MHC class II and CD86 in dendritic cells. IL-10-driven, MARCH1-dependent ubiquitination and degradation is antagonized by the CD83 TM domain.\",\n      \"method\": \"ENU-induced mutagenesis eliminating CD83 TM domain, genetic complementation, flow cytometry, functional T cell assays in mice\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — genetic loss-of-function with specific domain dissection, multiple orthogonal readouts\",\n      \"pmids\": [\"21220452\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"MARCH1 undergoes autoubiquitination via K48-linked polyubiquitin chains and regulates its own expression. MARCH1 homodimerizes and forms heterodimers with other MARCH family members. An inactive MARCH1 mutant (M1WI) has prolonged half-life; coexpression of active MARCH1 decreases M1WI levels, suggesting transubiquitination.\",\n      \"method\": \"Immunoprecipitation with polyubiquitin chain-specific antibodies, FRET energy transfer, co-immunoprecipitation, half-life measurements in transfected human cell lines\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods in single lab\",\n      \"pmids\": [\"22508929\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"MARCH1 cytoplasmic N-terminal tail contains endosomal sorting motifs. The C-terminal domain contains intracellular sorting signals and a functional 221VQNC224 motif that affects spatial organization of cytoplasmic regions and influences MARCH1 trafficking. Mutation of C-terminal tyrosine-based sorting signals reduces incorporation of MARCH1 into exosomes.\",\n      \"method\": \"Site-directed mutagenesis, reporter molecule fusions, subcellular localization assays, exosome isolation, structure-function analysis\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 — structure-function mutagenesis in single lab with multiple readouts\",\n      \"pmids\": [\"23264739\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"MARCH1-mediated MHC-II ubiquitination in dendritic cells is required for proper production of naturally occurring regulatory T cells (Treg) in the thymus. DCs deficient in MARCH1 or lacking MHC-II ubiquitination fail to generate antigen-specific Treg cells in vivo and in vitro.\",\n      \"method\": \"MARCH1 KO mice, MHC-II ubiquitination mutant mice, in vivo and in vitro Treg generation assays, antigen presentation assays\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — genetic KO and knockin epistasis with defined cellular phenotype, replicated\",\n      \"pmids\": [\"23712430\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Tollip competes with MARCH1 for binding to MHC-II molecules and strongly reduces MARCH1 protein levels, thereby antagonizing MARCH1-dependent MHC-II downregulation. Knockdown of Tollip increases HLA-DR expression; truncation of HLA-DR cytoplasmic tails abrogates the effect of Tollip.\",\n      \"method\": \"Tollip knockdown, MARCH1 co-expression, co-immunoprecipitation, flow cytometry in CIITA+ HeLa cells\",\n      \"journal\": \"Results in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — single lab, Co-IP plus functional knockdown\",\n      \"pmids\": [\"24600555\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"March-I ubiquitination of pMHC-II promotes degradation of newly synthesized pMHC-II in dendritic cells and prevents recycling of internalized pMHC-II from the cell surface back to the plasma membrane, instead targeting it to lysosomes. Acute APC activation terminates March-I expression, enabling efficient pMHC-II recycling and preventing lysosomal targeting.\",\n      \"method\": \"MHC-II ubiquitination mutant mice, biochemical recycling assays, lysosomal targeting assays, functional antigen presentation assays in DCs and B cells\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — reconstitution in primary cells with ubiquitination mutant KI mice plus multiple biochemical assays\",\n      \"pmids\": [\"26240324\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"IL-10 stimulates expression of March-I in activated macrophages, thereby down-regulating MHC-II, CD86, and antigen presentation to CD4 T cells. By contrast, IL-10 does not stimulate March-I expression in dendritic cells and does not suppress MHC-II or CD86 on DCs, establishing a cell-type-specific mechanism of IL-10-mediated immunosuppression.\",\n      \"method\": \"MARCH-I KO macrophages and DCs, flow cytometry, antigen presentation assays, IL-10 stimulation in primary cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — KO cells with multiple orthogonal functional readouts, replicated findings\",\n      \"pmids\": [\"26408197\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"MARCH1 impairs cellular insulin action by ubiquitinating the insulin receptor (INSR) to decrease cell surface INSR levels in the basal state (before insulin stimulation). March1 loss-of-function enhances, and March1 overexpression impairs, hepatic insulin sensitivity in mice.\",\n      \"method\": \"Large-scale RNAi screen, March1 KO mice, March1 overexpression mouse model, INSR ubiquitination assays, insulin signaling assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — RNAi screen plus KO and OE mouse models with defined biochemical and physiological phenotypes\",\n      \"pmids\": [\"27577745\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"March-I is ubiquitinated on non-lysine residues (lysine-independent ubiquitination) by an unidentified E3 ligase together with the ubiquitin-conjugating enzyme Ube2D1. March-I E3 ligase activity is not required for its own ubiquitination. Knockdown of Ube2D1 impairs March-I ubiquitination and increases March-I expression, enhancing March-I-dependent MHC-II downregulation.\",\n      \"method\": \"Lysine-less March-I variant expression, Ube2D1 knockdown, ubiquitination assays, western blot in transfected cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — mutagenesis plus siRNA knockdown with biochemical readouts in single lab\",\n      \"pmids\": [\"29414787\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"MARCH1-mediated ubiquitination of MHC-II indirectly regulates MHC-I surface expression in B cells and dendritic cells. Absence of MARCH1 reduces surface MHC-I expression not by direct MARCH1 ubiquitination of MHC-I but through altered MHC-II trafficking, establishing an intersection between MHC-I and MHC-II pathways.\",\n      \"method\": \"MARCH1 KO mice, MHC-II KO in March1-/- cells, MHC-II ubiquitination mutant replacement, flow cytometry, CD8 T cell antigen presentation assays\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — epistasis with multiple KO and knockin combinations, functional antigen presentation readout\",\n      \"pmids\": [\"30001419\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"MARCH1 ubiquitin-dependent turnover of MHC-II is critical for maintaining homeostasis of lipid rafts and the tetraspanin web in dendritic cells. Lack of MHC-II ubiquitination causes accumulation of excessive MHC-II in the plasma membrane, disrupting lipid rafts and tetraspanin web, and impairing DC engagement of thymocytes for Treg differentiation.\",\n      \"method\": \"MARCH1 KO mice, MHC-II ubiquitination mutant mice, lipid raft fractionation, tetraspanin web analysis, thymic Treg differentiation assays\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple KO/KI models with biochemical membrane domain analysis and functional cellular assays\",\n      \"pmids\": [\"29371232\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Both DCs and B cells possess a distinct isoform of March-I whose expression is regulated by a promoter located within the March-I gene. A core APC-specific promoter drives March-I expression in DCs and B cells but not fibroblasts; downstream regulatory elements in the first coding exon confer activation-induced down-regulation in APCs.\",\n      \"method\": \"March-I promoter-GFP reporter assays, promoter truncation analysis, activated DCs and B cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reporter assays with systematic promoter dissection in single lab\",\n      \"pmids\": [\"29378848\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"March1 inhibits MAVS/STING/TRIF-induced type I interferon signaling in vitro and in vivo. In malaria-infected hosts, March1 deficiency reduces IFN-I production by activating inhibitors SOCS1, USP18, and TRIM24 and altering immune cell populations, revealing a role in innate immune signaling beyond antigen presentation.\",\n      \"method\": \"March1 KO mice, Plasmodium yoelii infection model, type I IFN signaling assays, in vitro MAVS/STING/TRIF stimulation\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — KO mouse model with in vitro and in vivo signaling assays, single lab\",\n      \"pmids\": [\"32606244\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"MARCH1 ubiquitination-deficient DCs are poor stimulators of naive CD4 T cells and secrete IL-12 in response to LPS poorly, despite high surface pMHC-II. These functional and gene transcription defects are cell-intrinsic and are reversed by LPS activation. Single-cell RNA sequencing demonstrates that these DCs have an altered gene expression signature.\",\n      \"method\": \"MHC-II ubiquitination-mutant mouse DCs, naive CD4 T cell stimulation assays, scRNA-seq, IL-12 secretion assays\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — KI mouse model with scRNA-seq and multiple functional assays\",\n      \"pmids\": [\"33318291\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MARCH1 regulates MHC-II and CD86 specifically in professional and atypical antigen-presenting cells of hematopoietic origin (including neutrophils, eosinophils, monocytes) but not in non-hematopoietic cells, where MARCH8 operates. Unbiased proteomic profiling of the plasma membrane established CD86 and MHC-II as the primary in vivo substrates of MARCH1.\",\n      \"method\": \"MARCH1 and MARCH8 KO mice, unbiased plasma membrane proteomic profiling of primary immune cells\",\n      \"journal\": \"Current research in immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — unbiased proteomics on primary cells from KO mice, definitive substrate identification\",\n      \"pmids\": [\"35492398\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"DC induction of TH2 cells depends on MARCH1 ubiquitin ligase in lymph node-resident DCs. The pro-TH2 effect requires ubiquitin acceptor sites of both MHC-II and CD86 (the two MARCH1 substrates), and depends on TCR signaling and GATA-3 induction from naive CD4 T cells by LN-resident (not migratory) DCs.\",\n      \"method\": \"MARCH1 KO mice, MHC-II and CD86 ubiquitin-acceptor site mutant mice, TH2 differentiation assays, DC subset depletion, GATA-3 expression analysis\",\n      \"journal\": \"Science immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple KO and KI models with epistatic analysis and functional T cell differentiation readouts\",\n      \"pmids\": [\"34652961\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MARCH1 promotes OX40L expression in allergen-stimulated dendritic cells by ubiquitinating and degrading HDAC11. HDAC11 normally combines with KLF4 to decrease OX40L promoter activity; MARCH1-driven HDAC11 degradation thus de-represses OX40L expression.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assays, luciferase promoter assays, immunofluorescence co-localization, Western blot in DCs from asthmatic patients and animal models\",\n      \"journal\": \"Journal of asthma and allergy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus ubiquitination assay plus functional promoter assay in single lab\",\n      \"pmids\": [\"34385821\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MARCH1 recognizes CD86 through a specific surface in the hydrophobic core of the CD86 transmembrane domain, prominently featuring a proline at position 254, distinct from the recognition mode of viral KSHV MIR2 which requires an aspartic acid in the extracellular juxtamembrane region. This defines the MARCH1 substrate recognition mechanism for CD86.\",\n      \"method\": \"Deep mutational scanning of CD86 transmembrane domain, functional downregulation assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — systematic deep mutational scanning defining recognition surface at residue resolution\",\n      \"pmids\": [\"34157285\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"MARCH1 isoform 1 (MARCH1.1) restricts influenza A virus (IAV) replication whereas isoform 2 (MARCH1.2) does not. The 16 N-terminal residues of MARCH1.2's cytoplasmic domain suppress IAV restriction activity, as deletion of these residues restores IAV inhibition.\",\n      \"method\": \"Doxycycline-inducible MARCH1 isoform overexpression, viral titer assays, sequential N-terminal deletion mapping\",\n      \"journal\": \"Viruses\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — domain mapping with functional virus replication assays in single lab\",\n      \"pmids\": [\"36423158\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"MARCH1 mediates ubiquitination and degradation of the transferrin receptor (TfR) during HCMV infection, regulating cellular iron levels and the labile iron pool. MARCH1 knockdown leads to decreased infectious viral titers and increased ROS, lipid peroxidation, and mitochondrial dysfunction.\",\n      \"method\": \"MARCH1 knockdown, TfR expression analysis, labile iron pool measurement, viral titer assays, ROS and lipid peroxidation assays during HCMV infection\",\n      \"journal\": \"Journal of virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — knockdown with multiple functional readouts in single lab\",\n      \"pmids\": [\"35045264\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MARCHF1 acts as a novel E3 ligase for GPX4, promoting its ubiquitination and degradation, thereby inducing ferroptosis. BaP/BPDE exposure upregulates MARCHF1 to promote GPX4 degradation in endothelial cells.\",\n      \"method\": \"MARCHF1 overexpression/knockdown, GPX4 ubiquitination assay, ferroptosis assays in HUVECs and mouse miscarriage model\",\n      \"journal\": \"Environment international\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — ubiquitination assay plus cellular functional readout in single lab\",\n      \"pmids\": [\"37802009\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MARCH1 and MARCH2 retain Ebola virus glycoprotein (GP) at the trans-Golgi network by interacting with the furin P domain, blocking furin cleavage of EBOV GP and impairing pseudotyped virus infectivity.\",\n      \"method\": \"MARCH1/2 overexpression, EBOV GP-pseudotyped virus infectivity assays, furin co-immunoprecipitation, subcellular localization analysis\",\n      \"journal\": \"Journal of medical virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus functional virus assay plus subcellular localization in single lab\",\n      \"pmids\": [\"38299743\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MARCH1 interacts with TBK1 and promotes K63-linked ubiquitination of TBK1, which attenuates TBK1 interaction with mTOR and thereby inhibits growth factor-induced mTOR signaling. MARCH1 also interacts with STING. MARCH1 deficiency-induced faster proliferation is reversed by mTOR, STING, or TBK1 inhibition.\",\n      \"method\": \"Co-immunoprecipitation, denatured Co-IP for ubiquitination, MARCH1 overexpression/knockdown, mTOR signaling assays, clonogenic and wound healing assays\",\n      \"journal\": \"BMC cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus ubiquitination assay plus epistasis via inhibitors in single lab\",\n      \"pmids\": [\"39061024\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MARCH1 mediates ubiquitination and degradation of PCSK9 in brain neurons under ischemic conditions. MARCH1-mediated PCSK9 downregulation reduces brain damage by inhibiting NLRP3 inflammasome activation and pyroptosis, and by upregulating LDLR.\",\n      \"method\": \"Cycloheximide assay, co-immunoprecipitation, MARCH1/PCSK9 ectopic expression and knockdown, MCAO/R mouse model and OGD/R neuronal model\",\n      \"journal\": \"Mammalian genome\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus ubiquitination assay plus in vivo/in vitro models in single lab\",\n      \"pmids\": [\"39115562\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MARCH1 interacts with GABAB receptors specifically under ischemic/excitotoxic conditions and downregulates plasma membrane GABAB receptor levels by inhibiting fast receptor recycling. An interfering peptide blocking the MARCH1/GABAB interaction restored receptor expression and prevented progressive neuronal death.\",\n      \"method\": \"Co-immunoprecipitation, MARCH1 upregulation assays under ischemia, plasma membrane receptor quantification, interfering peptide treatment, neuronal viability assays\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus functional rescue with interfering peptide, single lab\",\n      \"pmids\": [\"39779794\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MARCHF1 interacts with and promotes ubiquitination and degradation of PHLPP2 in oral squamous cell carcinoma cells, enhancing cell proliferation and suppressing apoptosis.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, MARCH1 knockdown/overexpression, proliferation and apoptosis assays, in vivo tumor grafting\",\n      \"journal\": \"Clinical & translational oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus ubiquitination assay plus in vivo model in single lab\",\n      \"pmids\": [\"35122633\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CD83 suppresses endogenous March-I-dependent MHC-II ubiquitination, endocytosis, and degradation in mouse spleen DCs. Endogenous March-I protein is expressed at very low levels (~500 molecules/cell in DCs) with a very short half-life; March-I mRNA, protein, and MHC-II ubiquitination are rapidly terminated upon DC or B cell activation.\",\n      \"method\": \"V5 epitope knock-in to endogenous March-I gene, quantitative flow cytometry, March-I half-life measurement, activated DC/B cell functional assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — endogenous protein tagging plus quantitative biochemical analysis with functional validation\",\n      \"pmids\": [\"40397676\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MARCHF1 interacts with REST (repressor element-1 silencing transcription factor) and promotes its ubiquitination and degradation, thereby de-repressing transcription of mitochondrial transcription factor TFAM, supporting mitochondrial function and breast cancer cell proliferation.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, MARCHF1 knockdown/overexpression, TFAM mRNA analysis, mitochondrial function assays, in vivo tumor model\",\n      \"journal\": \"Cell biology international\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus ubiquitination assay plus functional pathway analysis in single lab\",\n      \"pmids\": [\"39428668\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MARCHF1 interacts with and promotes ubiquitination-mediated degradation of MYCT1, a candidate tumor suppressor, facilitating AML cell proliferation and inhibiting apoptosis and differentiation. POU2F2 transcription factor positively regulates MARCH1 transcription in AML.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, MARCH1 knockdown/overexpression, MARCH1 promoter analysis, AML mouse in vivo model\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — Co-IP plus ubiquitination assay plus in vivo model in single lab\",\n      \"pmids\": [\"40533483\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"SARS-CoV-2 M protein interacts with GPX4 (at R72 residue) and promotes its degradation via MARCHF1 E3 ubiquitin ligase, leading to ferroptosis through the MARCHF1-GPX4 axis.\",\n      \"method\": \"Co-immunoprecipitation, GPX4-M interaction mapping (R72 mutation), MARCHF1-dependent ubiquitination assay, ferroptosis assays\",\n      \"journal\": \"Journal of medical virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — interaction mapping with mutagenesis plus ubiquitination assay in single lab\",\n      \"pmids\": [\"40186530\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MARCH1 restricts HIV infectivity in macrophages by limiting incorporation of HIV envelope glycoproteins into nascent virions. HIV-1 Vpu counteracts this restriction by inducing microRNAs-25 and -93 that downregulate MARCH1 mRNA, via hijacking the cellular β-catenin pathway.\",\n      \"method\": \"miRNA-25/93 induction assays, MARCH1 mRNA knockdown, viral infectivity assays, β-catenin pathway analysis in macrophages\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — functional viral assay plus mechanistic pathway dissection in single lab\",\n      \"pmids\": [\"37773002\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MARCHF1 is a membrane-bound RING-CH E3 ubiquitin ligase that constitutively ubiquitinates MHC class II (at the beta-chain) and CD86 in antigen-presenting cells to promote their endocytosis, lysosomal degradation, and intracellular sequestration, thereby suppressing antigen presentation in resting DCs and monocytes; upon DC maturation or activation, MARCH1 expression is terminated (transcriptionally and post-translationally via Ube2D1-dependent lysine-independent self-ubiquitination and lysosomal proteolysis), stabilizing surface pMHC-II for effective CD4 T cell activation, while additional substrates including the insulin receptor, INSR, GPX4, TfR, PCSK9, TBK1, GABAB receptors, PHLPP2, HDAC11, REST, MYCT1, and SLC25A17 extend its regulatory roles to insulin signaling, ferroptosis, innate immune signaling, iron metabolism, and cancer cell biology.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"MARCHF1 is a membrane-associated RING-CH E3 ubiquitin ligase that serves as a master regulator of surface receptor turnover in antigen-presenting cells, controlling adaptive immune priming, T helper cell polarization, and thymic regulatory T cell generation. In resting dendritic cells, B cells, and monocytes, MARCHF1 constitutively ubiquitinates the MHC class II β-chain and CD86 costimulatory molecule, driving their endocytosis and lysosomal degradation; upon APC activation or maturation, MARCHF1 expression is rapidly extinguished at both transcriptional and post-translational levels (the protein has a half-life under 30 minutes and is expressed at ~500 molecules per DC), thereby stabilizing surface pMHC-II–CD86 complexes for productive CD4 T cell stimulation [PMID:18305173, PMID:19880452, PMID:40397676]. Unbiased plasma membrane proteomics confirms MHC-II and CD86 as the primary physiological substrates in hematopoietic APCs, and MARCHF1-dependent MHC-II ubiquitination maintains lipid raft and tetraspanin web homeostasis essential for Treg generation and TH2 polarization [PMID:35492398, PMID:29371232, PMID:34652961]. Beyond immune regulation, MARCHF1 ubiquitinates the insulin receptor to modulate hepatic insulin sensitivity, promotes ferroptosis by targeting GPX4 for degradation, regulates TBK1 via K63-linked ubiquitination to attenuate mTOR signaling, and restricts replication of influenza A virus and HIV by limiting viral glycoprotein availability [PMID:27577745, PMID:37802009, PMID:39061024, PMID:36423158, PMID:37773002].\",\n  \"teleology\": [\n    {\n      \"year\": 2008,\n      \"claim\": \"The identity of the E3 ligase responsible for MHC-II turnover in resting DCs was unknown; two independent studies established that MARCHF1 ubiquitinates MHC-II β-chain to drive its internalization, and that IL-10 induces MARCHF1 to downregulate MHC-II in monocytes, defining MARCHF1 as the key MHC-II ubiquitin ligase in professional APCs.\",\n      \"evidence\": \"Co-immunoprecipitation, ubiquitination assays, and siRNA knockdown in primary human DCs and monocytes\",\n      \"pmids\": [\"18305173\", \"18389477\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of MARCHF1–MHC-II interaction not defined\", \"E2 enzyme(s) partnering with MARCHF1 for MHC-II ubiquitination not identified\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Whether MARCHF1-mediated MHC-II ubiquitination was physiologically required in vivo was untested; MARCH-I knockout and MHC-II ubiquitination-site knockin mice demonstrated that MARCHF1-dependent MHC-II ubiquitination is essential for steady-state cDC function, while structure-function analysis revealed the protein's extremely short half-life and lysosomal degradation.\",\n      \"evidence\": \"MARCH-I KO mice, MHC-II ubiquitin-acceptor KI mice, antigen presentation assays, lysosomal inhibitor studies, domain mutagenesis\",\n      \"pmids\": [\"19917682\", \"19880452\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of activation-induced MARCHF1 transcriptional silencing not resolved\", \"Contribution of individual cytoplasmic tail domains to in vivo function unclear\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"How surface MHC-II is protected from MARCHF1 during DC maturation was unknown; CD83's transmembrane domain was shown to block MARCHF1–MHC-II association, providing a mechanistic counterbalance to MARCHF1 activity.\",\n      \"evidence\": \"ENU mutagenesis eliminating CD83 TM domain, genetic complementation, T cell functional assays in mice\",\n      \"pmids\": [\"21220452\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct CD83 TM–MARCHF1 TM interaction interface not structurally resolved\", \"Whether CD83 also protects CD86 from MARCHF1 independently of MHC-II not tested\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"MARCHF1 self-regulation was poorly understood; autoubiquitination via K48-linked chains, homodimerization, and trans-ubiquitination of inactive partners were demonstrated, along with identification of cytoplasmic sorting motifs directing MARCHF1 trafficking including exosome incorporation.\",\n      \"evidence\": \"FRET, Co-IP with chain-specific antibodies, half-life measurements, site-directed mutagenesis and exosome isolation\",\n      \"pmids\": [\"22508929\", \"23264739\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological role of MARCHF1 in exosomes not established\", \"Whether homodimerization is required for substrate ubiquitination unknown\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"The immunological consequence of MARCHF1-mediated MHC-II ubiquitination for T cell tolerance was unknown; MARCHF1-dependent MHC-II ubiquitination proved essential for thymic regulatory T cell generation, and Tollip was identified as a competitive antagonist of MARCHF1 binding to MHC-II.\",\n      \"evidence\": \"MARCH1 KO and MHC-II ubiquitination mutant mice with in vivo Treg assays; Tollip knockdown and Co-IP in CIITA+ HeLa cells\",\n      \"pmids\": [\"23712430\", \"24600555\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which Tollip reduces MARCHF1 protein levels not clarified\", \"Whether Tollip–MARCHF1 competition occurs in primary DCs in vivo not confirmed\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"How MARCHF1 controls the fate of internalized pMHC-II was unclear; MARCHF1-dependent ubiquitination was shown to redirect internalized pMHC-II from recycling to lysosomal degradation, and IL-10-induced MARCHF1 expression was found to be cell-type specific—operating in macrophages but not DCs.\",\n      \"evidence\": \"MHC-II ubiquitination mutant mice, biochemical recycling/lysosomal targeting assays, MARCH-I KO macrophages and DCs with antigen presentation readouts\",\n      \"pmids\": [\"26240324\", \"26408197\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Sorting adaptors linking ubiquitinated MHC-II to lysosomal targeting not identified\", \"Whether other cytokines besides IL-10 regulate MARCHF1 in macrophages not systematically examined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"MARCHF1 substrate range beyond immune molecules was unexplored; an RNAi screen and mouse models revealed that MARCHF1 ubiquitinates the insulin receptor to control surface INSR levels and hepatic insulin sensitivity, establishing a metabolic role.\",\n      \"evidence\": \"Large-scale RNAi screen, March1 KO and overexpression mice, INSR ubiquitination and insulin signaling assays\",\n      \"pmids\": [\"27577745\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether MARCHF1-INSR interaction occurs in tissues other than liver not tested\", \"MARCHF1 recognition determinants on the INSR not mapped\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Multiple mechanistic facets were clarified: MARCHF1 itself undergoes lysine-independent ubiquitination via Ube2D1; MARCHF1-dependent MHC-II ubiquitination indirectly modulates MHC-I surface expression; MARCHF1 controls lipid raft and tetraspanin web homeostasis; and an APC-specific promoter with activation-responsive elements was defined.\",\n      \"evidence\": \"Ube2D1 knockdown and lysine-less MARCHF1 mutants; MARCH1/MHC-II double-KO epistasis; lipid raft fractionation in KO/KI mice; promoter-GFP reporter truncation assays\",\n      \"pmids\": [\"29414787\", \"30001419\", \"29371232\", \"29378848\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The E3 ligase mediating MARCHF1's own lysine-independent ubiquitination not identified\", \"Structural basis for MHC-II ubiquitination effects on lipid rafts not elucidated\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Whether MARCHF1 functions beyond antigen presentation in innate immunity was unknown; MARCHF1 was shown to modulate MAVS/STING/TRIF-induced type I interferon production, and MARCHF1-deficient DCs exhibited intrinsic transcriptional and functional defects despite high surface pMHC-II.\",\n      \"evidence\": \"March1 KO mice with Plasmodium infection, IFN-I signaling assays; MHC-II ubiquitination-mutant DCs with scRNA-seq and T cell stimulation\",\n      \"pmids\": [\"32606244\", \"33318291\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct substrates mediating MARCHF1's effect on IFN-I signaling not identified at this stage\", \"Causal link between altered DC transcriptome and poor T cell stimulation not resolved\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Multiple advances defined substrate specificity and physiological impact: deep mutational scanning revealed that MARCHF1 recognizes CD86 via a proline-centered hydrophobic surface in its transmembrane domain; unbiased proteomics confirmed MHC-II and CD86 as primary in vivo substrates restricted to hematopoietic APCs; MARCHF1-dependent ubiquitination of both substrates was required for TH2 polarization by lymph node DCs; and HDAC11 was identified as a substrate linking MARCHF1 to OX40L de-repression in allergic DCs.\",\n      \"evidence\": \"Deep mutational scanning of CD86 TM; plasma membrane proteomics from MARCH1/MARCH8 KO mice; MHC-II/CD86 ubiquitin-acceptor mutant mice with TH2 assays; HDAC11 Co-IP and promoter assays in asthmatic DCs\",\n      \"pmids\": [\"34157285\", \"35492398\", \"34652961\", \"34385821\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether MARCHF1 TM domain directly contacts CD86 TM domain awaits structural confirmation\", \"HDAC11 as MARCHF1 substrate reported by single lab only\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"MARCHF1's antiviral functions were expanded: isoform-specific restriction of influenza A virus was mapped to N-terminal cytoplasmic residues, and MARCHF1 was found to ubiquitinate the transferrin receptor during HCMV infection to regulate iron homeostasis and viral replication.\",\n      \"evidence\": \"Doxycycline-inducible isoform expression with IAV titer assays; TfR expression/iron assays during HCMV infection with MARCHF1 knockdown\",\n      \"pmids\": [\"36423158\", \"35045264\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct ubiquitination of TfR by MARCHF1 not shown with purified components\", \"Whether IAV restriction involves a defined MARCHF1 substrate unclear\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"MARCHF1 was established as an E3 ligase for GPX4, linking it to ferroptosis regulation, and was shown to restrict HIV infectivity in macrophages by limiting envelope glycoprotein incorporation into virions—a restriction counteracted by HIV Vpu via miR-25/93-mediated MARCHF1 downregulation.\",\n      \"evidence\": \"GPX4 ubiquitination assays and ferroptosis readouts in HUVECs; miRNA induction assays, MARCHF1 mRNA knockdown, viral infectivity assays in macrophages\",\n      \"pmids\": [\"37802009\", \"37773002\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"GPX4 as direct MARCHF1 substrate confirmed in a single lab\", \"Whether MARCHF1 restricts HIV by ubiquitinating envelope glycoproteins directly not demonstrated\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"MARCHF1's substrate repertoire expanded to signaling and metabolic regulators: K63-linked ubiquitination of TBK1 attenuates mTOR signaling; ubiquitination-dependent degradation of PCSK9 in neurons protects against ischemic brain injury; MARCHF1 interaction with GABAB receptors under ischemia blocks receptor recycling; and MARCHF1 retains Ebola virus GP at the trans-Golgi via furin interaction.\",\n      \"evidence\": \"Co-IP and ubiquitination assays for TBK1, PCSK9, and GABAB receptors; MCAO/R mouse model; interfering peptide rescue; EBOV-pseudovirus infectivity and furin Co-IP\",\n      \"pmids\": [\"39061024\", \"39115562\", \"39779794\", \"38299743\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Each new substrate reported by a single laboratory; independent replication needed\", \"Whether TBK1 K63-ubiquitination by MARCHF1 requires a specific E2 enzyme unknown\", \"Physiological relevance of MARCHF1-GABAB interaction outside ischemia not addressed\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Endogenous MARCHF1 protein was quantified for the first time (~500 molecules/DC) using a V5 knock-in, confirming CD83 as an endogenous antagonist; additional cancer-relevant substrates PHLPP2, REST, and MYCT1 were identified, and SARS-CoV-2 M protein was shown to hijack MARCHF1-dependent GPX4 degradation to induce ferroptosis.\",\n      \"evidence\": \"V5 epitope knock-in to endogenous locus with quantitative flow cytometry; Co-IP/ubiquitination assays and in vivo tumor models for PHLPP2/REST/MYCT1; M protein–GPX4 interaction mapping with MARCHF1-dependent ubiquitination assays\",\n      \"pmids\": [\"40397676\", \"35122633\", \"39428668\", \"40533483\", \"40186530\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Cancer-related substrates each reported by single labs; validation in independent systems pending\", \"Structural basis for MARCHF1 substrate selectivity across diverse transmembrane and soluble proteins remains unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"No high-resolution structure of MARCHF1 exists, and the mechanism by which a single RING-CH E3 ligase recognizes such a diverse set of transmembrane and cytoplasmic substrates (MHC-II, CD86, INSR, GPX4, TBK1, TfR, PCSK9, GABAB receptor, PHLPP2, REST, MYCT1, HDAC11) remains unresolved. The E3 ligase that mediates MARCHF1's own lysine-independent ubiquitination has not been identified.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No crystal or cryo-EM structure of MARCHF1 or any MARCHF1–substrate complex\", \"E3 ligase targeting MARCHF1 for degradation not identified\", \"Systematic comparison of MARCHF1 vs MARCH8 substrate selectivity determinants lacking\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 1, 3, 5, 9, 11, 13, 14, 18, 19, 20, 21, 23, 24, 26, 27, 29, 31, 32, 33]},\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [0, 1, 5, 11, 24, 26]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 1, 11, 18, 21, 28]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [2, 6, 9]},\n      {\"term_id\": \"GO:0005764\", \"supporting_discovery_ids\": [2, 9]},\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [25]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [0, 1, 3, 4, 7, 9, 10, 13, 14, 17, 18, 19]},\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 1, 5, 11, 12, 24, 26, 29, 31, 32]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [11, 16, 26, 27]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [24, 33]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [6, 9, 25]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"HLA-DRB1\",\n      \"CD86\",\n      \"INSR\",\n      \"CD83\",\n      \"GPX4\",\n      \"TBK1\",\n      \"TFRC\",\n      \"PCSK9\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}