{"gene":"MID1","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":1999,"finding":"MID1 protein associates with microtubules and influences microtubule dynamics in overexpressing cells; endogenous MID1 co-localizes with tubulin in subcellular fractions and associates with microtubules in an in vitro assembly assay. OS patient mutations abolish microtubule association, causing cytoplasmic aggregation instead.","method":"GFP tagging, subcellular fractionation, in vitro microtubule assembly assay, immunofluorescence","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (live imaging, fractionation, in vitro assembly), replicated with patient mutations as controls","pmids":["10077590"],"is_preprint":false},{"year":2002,"finding":"MID1 and MID2 interact with Alpha 4 (regulatory subunit of PP2-type phosphatases) via their B-box domains; the coiled-coil motifs mediate homo- and heterodimerization, and dimerization is required for association of the MID1/Alpha4 complex with microtubules.","method":"Yeast two-hybrid screening, domain-deletion analysis","journal":"BMC cell biology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — yeast two-hybrid plus domain mapping, single lab but consistent domain dissection","pmids":["11806752"],"is_preprint":false},{"year":2004,"finding":"MID1 interacts with Mig12 via its coiled-coil domain; when co-expressed, Mig12 is recruited to thick microtubule bundles by MID1. The MID1-Mig12 complex stabilizes microtubules (bundles are resistant to depolymerizing agents and composed of acetylated tubulin).","method":"Yeast two-hybrid, co-immunoprecipitation, co-transfection with immunofluorescence, microtubule depolymerization assay","journal":"BMC cell biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP and functional microtubule stabilization assay, single lab","pmids":["15070402"],"is_preprint":false},{"year":2008,"finding":"MID1 assembles a microtubule-associated ribonucleoprotein complex that includes elongation factor 1α (EF-1α), RACK1, Annexin A2, Nucleophosmin, and small ribosomal subunit proteins; the complex specifically associates with G- and U-rich RNAs and incorporates MID1 mRNA. OS patient mutations in MID1 abolish its interaction with EF-1α.","method":"Yeast two-hybrid, immunofluorescence, affinity purification, microtubule assembly co-fractionation, immunoprecipitation, RNA binding assay","journal":"Human genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — five independent orthogonal methods in one study confirming the complex and RNA association","pmids":["18172692"],"is_preprint":false},{"year":2008,"finding":"MID1 undergoes active, bi-directional transport along microtubules dependent on both kinesins and dyneins. Transport is regulated by MAP kinase and PP2A-mediated phosphorylation (simulating permanent phosphorylation at Ser96 stops migration). Knockdown of alpha4, inhibition of PP2A by okadaic acid/fostriecin, or OS patient B-box1 missense mutations block active transport while preserving microtubule association.","method":"FRAP (fluorescence recovery after photobleaching), pharmacological inhibition (colcemide, okadaic acid, fostriecin), siRNA knockdown, phosphomimetic mutations","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 2 / Strong — FRAP with multiple pharmacological and genetic perturbations, mechanistic dissection of phosphorylation dependence","pmids":["18949047"],"is_preprint":false},{"year":2010,"finding":"MID1 and its paralog MID2 are required for neural tube closure in Xenopus; MID knockdown destabilizes and disorganizes apicobasally polarized microtubules in the neural plate, disrupting epithelial morphology. MIDs and their interactor Mig12 cooperate for microtubule stabilization during neural plate remodeling.","method":"Morpholino-mediated knockdown, immunofluorescence, live imaging of microtubule dynamics","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean loss-of-function with defined cellular and microtubule phenotype, Xenopus ortholog study, single lab","pmids":["20534674"],"is_preprint":false},{"year":2011,"finding":"MID1 functions as an E3 ligase targeting the catalytic subunit of PP2A (PP2A-C) for ubiquitin-mediated degradation. Elevated PP2A resulting from MID1 depletion or proteasome inhibition disrupts the mTOR/Raptor complex and down-regulates mTORC1 signaling (reduced S6K1 phosphorylation, cell size, cap-dependent translation). This is rescued by wild-type MID1 re-expression or constitutively active mTOR.","method":"siRNA knockdown, proteasome inhibition, co-immunoprecipitation, phosphorylation assays, rescue experiments with WT MID1 or activated mTOR, OS patient-derived fibroblasts","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal experiments including patient cells, knockdown, rescue, and co-IP, single lab with mechanistic depth","pmids":["21555591"],"is_preprint":false},{"year":2011,"finding":"Human MID1 RING domain exhibits E3 ubiquitin ligase activity in vitro, catalyzing auto-polyubiquitination; tandem RING-Bbox1 and RING-Bbox1-Bbox2 constructs show greater activity than individual domains. MID1 facilitates Lys63-linked ubiquitin chain elongation and polyubiquitinates its Bbox1 domain at Lys154. A C-terminal peptide of alpha4 that binds Bbox1 is monoubiquitinated and inhibits polyubiquitin product formation.","method":"In vitro E3 ligase assay, ubiquitin linkage mutants, mass spectrometry, domain mutagenesis","journal":"Journal of molecular biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with mutagenesis and mass spectrometry, single lab","pmids":["21296087"],"is_preprint":false},{"year":2013,"finding":"Expanded CAG repeat RNA (from huntingtin and other polyglutamine disease genes) binds to a complex containing MID1, PP2A, and 40S ribosomal S6 kinase. Binding increases with CAG repeat length and stimulates translation of the repeat-containing mRNA in a MID1-, PP2A-, and mTOR-dependent manner.","method":"RNA immunoprecipitation, co-immunoprecipitation, translation reporter assays, siRNA knockdown","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal biochemical and functional assays establishing both the complex composition and translational output","pmids":["23443539"],"is_preprint":false},{"year":2013,"finding":"MID1-dependent PP2Ac turnover is required for normal axon development; silencing Mid1 increases PP2Ac levels, promoting axon growth and branching and disrupting callosal projections in vivo. Further knockdown of PP2Ac rescues the axonal phenotype in Mid1-depleted neurons.","method":"In vitro knockdown, Mid1 knockout mouse, in vivo brain imaging, genetic epistasis (double knockdown of Mid1 and PP2Ac)","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vitro and in vivo loss-of-function with genetic rescue epistasis establishing pathway position","pmids":["24194544"],"is_preprint":false},{"year":2013,"finding":"MID1 E3 ligase catalyzes polyubiquitination of alpha4 (regulatory subunit of PP2A); direct binding of alpha4 to the Bbox1 domain is required (a L146Q mutation abolishes alpha4 interaction and its polyubiquitination without affecting RING autoubiquitination). Full-length MID1 and RING-Bbox1 constructs catalyze alpha4 polyubiquitination; ubiquitination of alpha4 occurs within its last 105 amino acids.","method":"In vitro ubiquitination assay, dominant-negative MID1 stable cells, proteasome inhibition, mass spectrometry, mutagenesis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with mutagenesis, mass spectrometry, and cell-based validation, mechanistically rigorous","pmids":["23740247"],"is_preprint":false},{"year":2014,"finding":"MID1 protein complex associates with androgen receptor (AR) mRNA via purine-rich trinucleotide repeats and increases AR protein levels through enhanced translation (without changing mRNA levels or AR protein stability). Conversely, AR exerts a negative transcriptional feedback on MID1 via AR binding sites in the MID1 gene.","method":"Co-immunoprecipitation followed by PCR, RNA pull-down followed by western blot, siRNA knockdown, overexpression, reporter gene assays, chromatin immunoprecipitation","journal":"Molecular cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNA pull-down, Co-IP-PCR, and functional rescue in single lab, multiple methods","pmids":["24913494"],"is_preprint":false},{"year":2014,"finding":"MID1 E3 ligase catalyzes ubiquitination and proteasomal cleavage of Fu (Fused kinase), a regulator of GLI3 transcriptional activity in the SHH-GLI signaling pathway, linking the MID1-PP2A complex to GLI3 activity control.","method":"In vitro ubiquitination assay, co-immunoprecipitation, proteasome inhibition, cell-based reporter assays","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro ubiquitination combined with cell-based epistasis, single lab","pmids":["25278022"],"is_preprint":false},{"year":2014,"finding":"MID1 catalyzes in vitro ubiquitination of the PP2A catalytic subunit (PP2Ac) directly, in the absence of alpha4. In the presence of alpha4, PP2Ac ubiquitination is reduced. OS patient Bbox1 domain mutations (C142S, C145T, A130V/T) abolish polyubiquitination of alpha4 but not of PP2Ac, suggesting alpha4 dysregulation as the direct molecular consequence of these mutations.","method":"In vitro ubiquitination assay, domain mutagenesis, western blot","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with mutagenesis, single lab","pmids":["25207814"],"is_preprint":false},{"year":2014,"finding":"Metformin decreases BACE1 protein expression by interfering with the MID1 mRNA-protein complex, reducing BACE1 activity in primary neurons, human cell lines, and in vivo in mice.","method":"Western blot, pharmacological treatment, siRNA knockdown, in vivo mouse studies","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — convergent in vitro and in vivo evidence, single lab, mechanism linked to MID1 complex","pmids":["25025689"],"is_preprint":false},{"year":2016,"finding":"NMR solution structure of the MID1 COS (C-terminal subgroup One Signature) domain reveals a helix-loop-helix fold with a hydrophobic core and a basic patch of positively charged residues. Fusion of the COS domain to the coiled-coil (CC) domain confers microtubule binding; CC-COS constructs directly bind microtubules, establishing the structural basis for MID1 microtubule association.","method":"NMR structure determination (PDB: 5IM8), microtubule binding assay, domain fusion experiments","journal":"The FEBS journal","confidence":"High","confidence_rationale":"Tier 1 / Moderate — NMR structure with functional microtubule binding validation, single lab","pmids":["27367845"],"is_preprint":false},{"year":2016,"finding":"MID1 protein complex binds to ATXN2, ATXN3, and ATXN7 mRNAs in a CAG repeat length-dependent manner and induces protein synthesis of the cognate polyglutamine proteins in a repeat length-dependent manner, indicating a common translational regulatory mechanism for expanded CAG repeat mRNAs.","method":"RNA immunoprecipitation, translation reporter assays, western blot, siRNA knockdown","journal":"Frontiers in cellular neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — consistent biochemical and functional assays across multiple substrates, single lab","pmids":["27774050"],"is_preprint":false},{"year":2017,"finding":"Resveratrol decreases MID1 ubiquitin ligase expression, which reduces MID1-mediated ubiquitination and degradation of PP2A-C on microtubules, thereby increasing PP2A activity and reducing Tau phosphorylation at PP2A-dependent epitopes. MID1 expression is elevated in Alzheimer's disease tissue.","method":"Western blot, PP2A activity assay, phospho-tau immunoblot, pharmacological treatment with resveratrol","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pharmacological perturbation linked mechanistically to MID1 level change, with biochemical readouts, single lab","pmids":["29062069"],"is_preprint":false},{"year":2017,"finding":"Mid1 levels are reduced in Rac1/Rac3 double-knockout cerebellar granule neurons, and Mid1 depletion impairs neuritogenesis and reduces mTORC1 signaling, placing Mid1 downstream of Rac GTPases and upstream of mTORC1 in a Rac1-Mid1-mTORC1 pathway in cerebellar development.","method":"Conditional double knockout mouse, Mid1 siRNA depletion in primary neurons, mTORC1 signaling western blot, neurite morphology assay","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic double KO with epistasis supported by siRNA, single lab","pmids":["28512198"],"is_preprint":false},{"year":2018,"finding":"MID1 protein complex binds to and regulates translation of APP mRNA via the mTOR pathway; inhibition of the MID1 complex by metformin reduces APP protein levels and Aβ in an AD mouse model when treatment is initiated in an already-advanced disease state.","method":"RNA immunoprecipitation, western blot, mTOR pathway inhibition, primary neuron cultures, in vivo mouse treatment, behavioral phenotype","journal":"Cell death discovery","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro mRNA binding plus in vivo intervention, single lab, builds on established MID1-mTOR axis","pmids":["29531801"],"is_preprint":false},{"year":2019,"finding":"TRAIL signals through the MID1 ubiquitin ligase to deactivate PP2A, promoting pulmonary fibrosis; TRAIL-deficient mice and PP2A activator-treated mice are protected from bleomycin-induced fibrosis. Recombinant TRAIL increases collagen production in fibroblasts, reversible by PP2A activation.","method":"Genetic TRAIL-knockout mouse, pharmacological PP2A activation, in vitro fibroblast treatment, lung function measurement, human biopsy analysis","journal":"BMC pulmonary medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo genetic and pharmacological experiments with in vitro corroboration, single lab","pmids":["30732588"],"is_preprint":false},{"year":2021,"finding":"MID1 physically interacts with IRF3, induces K48-linked polyubiquitination of IRF3 at Lys313, and promotes proteasomal degradation of IRF3, thereby restricting type I interferon production and cellular antiviral response.","method":"Co-immunoprecipitation, in vitro/cellular ubiquitination assay, site-directed mutagenesis of ubiquitin acceptor site, IFN reporter assay, antiviral assay","journal":"Immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, ubiquitination assay with K48-linkage specificity, lysine mutagenesis, and functional IFN output, multiple orthogonal methods","pmids":["33513265"],"is_preprint":false},{"year":2022,"finding":"TRIM18 (MID1) recruits protein phosphatase PPM1A to dephosphorylate TBK1, inactivating TBK1 and blocking its interaction with MAVS and STING adaptors, thereby dampening antiviral interferon signaling. TRIM18 also stabilizes PPM1A by inducing K63-linked ubiquitination of PPM1A.","method":"Co-immunoprecipitation, immunoblot, siRNA knockdown, TRIM18 knockout mice with viral challenge, luciferase assay, ubiquitination assay","journal":"Journal of biomedical science","confidence":"High","confidence_rationale":"Tier 2 / Strong — Co-IP, in vivo KO with viral challenge, ubiquitination assay, multiple orthogonal methods across in vitro and in vivo models","pmids":["35909127"],"is_preprint":false},{"year":2021,"finding":"TRIM18 (MID1) promotes ubiquitin-mediated proteasomal degradation of PTP1B, which activates STAT3 signaling to promote renal epithelial-mesenchymal transition, inflammation, and fibrosis in diabetic kidney disease.","method":"Co-immunoprecipitation, ubiquitination assay, western blot, siRNA knockdown, overexpression in HK-2 cells, pharmacological STAT3 inhibition","journal":"Frontiers in physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, ubiquitination assay, and epistasis via PTP1B/STAT3 rescue, single lab","pmids":["34434118"],"is_preprint":false},{"year":2024,"finding":"MID1 promotes synoviocyte proliferation and migration by inducing ubiquitin-mediated proteasomal degradation of DPP4; DPP4 deficiency phenocopies MID1 overexpression and DPP4 reconstitution abolishes MID1-induced synoviocyte activation. In a collagen-induced arthritis model, Mid1 knockout completely protects mice from arthritis, and this protection is abolished by concurrent DPP4 knockout.","method":"Co-immunoprecipitation, proteomic analysis, ubiquitination assay, overexpression/knockdown in synoviocytes, collagen-induced arthritis in Mid1-/- and Mid1-/-Dpp4-/- double-knockout mice","journal":"Pharmacological research","confidence":"High","confidence_rationale":"Tier 2 / Strong — Co-IP, ubiquitination assay, in vivo double-KO epistasis, and functional rescue with DPP4 reconstitution","pmids":["38777113"],"is_preprint":false}],"current_model":"MID1 (TRIM18) is a microtubule-associated RING-Bbox-coiled-coil E3 ubiquitin ligase that assembles a large microtubule-anchored complex containing the PP2A catalytic subunit (PP2Ac), its regulatory subunit alpha4 (α4), translation factors (EF-1α, RACK1, ribosomal subunits), and specific mRNAs; it ubiquitinates PP2Ac (via K48-linked chains, targeted by alpha4 interaction through the Bbox1 domain), alpha4, DPP4, IRF3, Fu kinase, and PPM1A (K63-linked), thereby controlling PP2A activity, mTORC1 signaling, cap-dependent translation of target mRNAs (including CAG-repeat-containing mRNAs, AR mRNA, and APP mRNA), SHH-GLI and innate immune (TBK1-IFN) signaling pathways; the protein is actively transported along microtubules in a PP2A/alpha4/mTOR phosphorylation-dependent manner, and its COS domain directly mediates microtubule binding."},"narrative":{"mechanistic_narrative":"MID1 (TRIM18) is a microtubule-associated RING-Bbox-coiled-coil E3 ubiquitin ligase that couples microtubule dynamics to phosphatase control, protein translation, and signaling, with loss-of-function disrupting epithelial and neuronal microtubule architecture during development [PMID:10077590, PMID:20534674, PMID:27367845]. It binds microtubules directly through a helix-loop-helix COS domain acting in concert with the coiled-coil region, while coiled-coil-mediated dimerization is required for the assembled complex to associate with microtubules [PMID:27367845, PMID:11806752]; the protein is actively transported bidirectionally along microtubules by kinesins and dyneins in a manner gated by MAP kinase and PP2A-dependent phosphorylation [PMID:18949047]. The central biochemical activity of MID1 is RING-dependent ubiquitination, in which the Bbox1 domain recruits the PP2A regulatory subunit alpha4, and MID1 ubiquitinates both alpha4 and the PP2A catalytic subunit (PP2Ac) to drive their proteasomal turnover and thereby raise net PP2A activity when MID1 is lost [PMID:21296087, PMID:23740247, PMID:25207814, PMID:21555591]. By limiting PP2A, MID1 sustains mTORC1 signaling and cap-dependent translation, positioning it downstream of Rac GTPases and upstream of mTORC1 in neuronal morphogenesis and axon development [PMID:21555591, PMID:28512198, PMID:24194544]. MID1 also nucleates a microtubule-anchored ribonucleoprotein complex with EF-1α, RACK1, and ribosomal subunits that binds purine-rich and CAG-repeat-containing mRNAs and stimulates their translation in a PP2A/mTOR-dependent manner, including expanded CAG-repeat polyglutamine transcripts, androgen receptor mRNA, and APP mRNA [PMID:18172692, PMID:23443539, PMID:27774050, PMID:24913494, PMID:29531801]. Beyond PP2A, MID1 ubiquitinates additional substrates to control distinct pathways: Fused kinase in SHH-GLI signaling [PMID:25278022], IRF3 (K48-linked) and PPM1A (K63-linked) to restrain type I interferon and TBK1-dependent antiviral signaling [PMID:33513265, PMID:35909127], and DPP4 and PTP1B in inflammatory and fibrotic disease contexts [PMID:38777113, PMID:34434118]. Patient mutations in MID1 cause Opitz syndrome by abolishing microtubule association or, for Bbox1 mutations, selectively disrupting alpha4 binding and ubiquitination [PMID:10077590, PMID:25207814].","teleology":[{"year":1999,"claim":"Established MID1 as a microtubule-associated protein whose disease mutations mislocalize it, defining microtubules as its primary site of action.","evidence":"GFP tagging, subcellular fractionation, and in vitro microtubule assembly with patient mutation controls","pmids":["10077590"],"confidence":"High","gaps":["Did not identify the domain mediating microtubule binding","No molecular partners defined"]},{"year":2002,"claim":"Identified alpha4 (PP2-type phosphatase regulatory subunit) as a Bbox-binding partner and showed coiled-coil dimerization is required for microtubule association, linking MID1 to phosphatase regulation.","evidence":"Yeast two-hybrid and domain-deletion analysis","pmids":["11806752"],"confidence":"Medium","gaps":["No demonstration of catalytic consequence on PP2A","Single-lab Y2H without reciprocal in vivo validation"]},{"year":2004,"claim":"Showed MID1 recruits Mig12 to stabilize and bundle microtubules, defining a functional role in microtubule stabilization.","evidence":"Yeast two-hybrid, reciprocal Co-IP, and microtubule depolymerization assays","pmids":["15070402"],"confidence":"Medium","gaps":["Mechanism of bundle stabilization unresolved","Physiological context not established"]},{"year":2008,"claim":"Revealed MID1 assembles a microtubule-anchored ribonucleoprotein complex binding G/U-rich RNAs, extending its function from cytoskeleton to translation, with OS mutations disrupting EF-1α binding.","evidence":"Affinity purification, co-fractionation, RNA-binding, and Y2H across five orthogonal methods","pmids":["18172692"],"confidence":"High","gaps":["Translational output of the complex not yet measured","RNA target specificity beyond MID1 mRNA undefined"]},{"year":2008,"claim":"Demonstrated MID1 is actively transported along microtubules by motors in a phosphorylation-gated manner, mechanistically connecting PP2A/alpha4 to MID1 trafficking.","evidence":"FRAP with pharmacological PP2A inhibition, siRNA, and phosphomimetic mutations","pmids":["18949047"],"confidence":"High","gaps":["Kinase responsible for Ser96 phosphorylation in vivo not defined","Functional purpose of transport unclear"]},{"year":2011,"claim":"Defined MID1 as an E3 ligase that degrades PP2A-C to sustain mTORC1 signaling and cap-dependent translation, establishing the core MID1-PP2A-mTOR axis.","evidence":"siRNA, proteasome inhibition, Co-IP, rescue with WT MID1 or activated mTOR, and OS patient fibroblasts","pmids":["21555591"],"confidence":"High","gaps":["Ubiquitin linkage type on PP2Ac not specified here","Direct vs alpha4-bridged targeting not resolved"]},{"year":2011,"claim":"Reconstituted MID1 RING ligase activity in vitro, showing tandem RING-Bbox cooperation, K63 chain elongation, and Bbox1 autoubiquitination at Lys154.","evidence":"In vitro ligase assays with linkage mutants, mass spectrometry, and domain mutagenesis","pmids":["21296087"],"confidence":"High","gaps":["Physiological substrate beyond autoubiquitination not addressed here","E2 enzyme partner in cells undefined"]},{"year":2013,"claim":"Identified alpha4 and PP2Ac as direct MID1 substrates, mapping alpha4 ubiquitination to Bbox1-dependent recruitment and explaining how OS Bbox1 mutations dysregulate the complex.","evidence":"In vitro ubiquitination, dominant-negative cell lines, mass spectrometry, and mutagenesis (#10, #13)","pmids":["23740247","25207814"],"confidence":"High","gaps":["Relative in vivo contribution of alpha4 vs PP2Ac ubiquitination unresolved","Stoichiometry of alpha4-PP2Ac-MID1 complex undefined"]},{"year":2013,"claim":"Connected expanded CAG-repeat RNA to the MID1-PP2A-S6K complex and showed length-dependent stimulation of repeat-mRNA translation, linking MID1 to polyglutamine disease pathology.","evidence":"RNA immunoprecipitation, Co-IP, translation reporters, and siRNA","pmids":["23443539"],"confidence":"High","gaps":["Direct RNA-binding subunit within the complex not pinpointed","In vivo relevance to disease onset not tested"]},{"year":2013,"claim":"Established the physiological requirement for MID1-dependent PP2Ac turnover in axon development via genetic epistasis in vivo.","evidence":"Mid1 knockout mouse, in vivo brain imaging, and Mid1/PP2Ac double-knockdown rescue","pmids":["24194544"],"confidence":"High","gaps":["Downstream effectors of PP2A in axon growth not defined"]},{"year":2014,"claim":"Extended MID1 translational control to disease-relevant mRNAs (AR, APP) and to substrate Fu kinase in SHH-GLI signaling, broadening its regulatory reach.","evidence":"RNA pull-down, Co-IP-PCR, reporter assays, ChIP, and in vitro ubiquitination (#11, #12, #14)","pmids":["24913494","25278022","25025689"],"confidence":"Medium","gaps":["Sequence determinants of mRNA target selection incompletely mapped","Single-lab evidence for each target"]},{"year":2016,"claim":"Solved the COS domain structure and demonstrated CC-COS suffices for direct microtubule binding, providing the structural basis for MID1 cytoskeletal anchoring.","evidence":"NMR structure (PDB 5IM8) with microtubule-binding domain fusion assays","pmids":["27367845"],"confidence":"High","gaps":["Tubulin contact residues not mapped","Structure of full-length assembled complex unknown"]},{"year":2016,"claim":"Generalized the CAG-repeat translational mechanism across ataxin transcripts, establishing a common MID1 pathway for multiple polyglutamine diseases.","evidence":"RNA immunoprecipitation, translation reporters, and siRNA across ATXN2/3/7","pmids":["27774050"],"confidence":"Medium","gaps":["In vivo confirmation across disease models lacking","Single-lab functional series"]},{"year":2017,"claim":"Placed Mid1 downstream of Rac GTPases and upstream of mTORC1 in neuronal development and linked MID1-PP2A-Tau regulation to Alzheimer's disease pathology.","evidence":"Rac1/Rac3 double-knockout mice, siRNA, mTORC1 immunoblot, PP2A activity and phospho-Tau assays (#17, #18)","pmids":["28512198","29062069"],"confidence":"Medium","gaps":["Mechanism connecting Rac to MID1 expression undefined","Causal role in human AD not established"]},{"year":2019,"claim":"Identified TRAIL as an upstream input that signals through MID1 to deactivate PP2A, implicating the axis in pulmonary fibrosis.","evidence":"TRAIL-knockout mice, PP2A activator treatment, fibroblast assays, and human biopsies","pmids":["30732588"],"confidence":"Medium","gaps":["Direct biochemical link from TRAIL receptor to MID1 not defined","Single-lab disease model"]},{"year":2022,"claim":"Defined MID1/TRIM18 as a negative regulator of antiviral signaling through K48 degradation of IRF3 and PPM1A-mediated TBK1 dephosphorylation, with K63 stabilization of PPM1A.","evidence":"Reciprocal Co-IP, linkage-specific ubiquitination assays, lysine mutagenesis, IFN reporters, and TRIM18-knockout mice with viral challenge (#21, #22)","pmids":["33513265","35909127"],"confidence":"High","gaps":["Integration with microtubule/PP2A functions unclear","Cell-type specificity of immune restriction not mapped"]},{"year":2024,"claim":"Demonstrated MID1-driven degradation of DPP4 (and PTP1B/STAT3 in kidney disease) as a mechanism in inflammatory and fibrotic pathology, validated by in vivo double-knockout epistasis.","evidence":"Co-IP, proteomics, ubiquitination assays, and Mid1-/-Dpp4-/- collagen-induced arthritis mice with DPP4 reconstitution (#23, #24)","pmids":["38777113","34434118"],"confidence":"High","gaps":["Whether DPP4/PTP1B targeting depends on the alpha4/PP2A machinery unknown","Substrate recognition determinants undefined"]},{"year":null,"claim":"It remains unresolved how MID1 selects among its diverse substrates (PP2Ac, alpha4, IRF3, PPM1A, DPP4, PTP1B, Fu) and target mRNAs, and how microtubule anchoring, motor transport, ubiquitination, and translational control are integrated within a single complex.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified structural model of the assembled MID1 complex","Substrate-selection code unknown","Mechanism coupling RNA binding to ligase activity undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[6,7,10,13,21,22,23,24]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[6,10,12,13,21,22,24]},{"term_id":"GO:0003723","term_label":"RNA binding","supporting_discovery_ids":[3,8,11,16,19]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[0,2,15]},{"term_id":"GO:0045182","term_label":"translation regulator activity","supporting_discovery_ids":[8,11,16,19]}],"localization":[{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[0,2,4,15]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[0,3]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[6,7,10,13,21,22,24]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[6,12,18,20,22,23]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[21,22]},{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[3,8,11,16,19]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[5,9,18]}],"complexes":["MID1-alpha4-PP2A complex","MID1 microtubule-associated ribonucleoprotein complex"],"partners":["PPP2CA","IGBP1","MID2","MIG12","EEF1A","RACK1","IRF3","PPM1A"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O15344","full_name":"E3 ubiquitin-protein ligase Midline-1","aliases":["Midin","Putative transcription factor XPRF","RING finger protein 59","RING finger protein Midline-1","RING-type E3 ubiquitin transferase Midline-1","Tripartite motif-containing protein 18"],"length_aa":667,"mass_kda":75.3,"function":"Has E3 ubiquitin ligase activity towards IGBP1, promoting its monoubiquitination, which results in deprotection of the catalytic subunit of protein phosphatase PP2A, and its subsequent degradation by polyubiquitination","subcellular_location":"Cytoplasm; Cytoplasm, cytoskeleton; Cytoplasm, cytoskeleton, spindle","url":"https://www.uniprot.org/uniprotkb/O15344/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MID1","classification":"Not 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chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11796727","citation_count":18,"is_preprint":false},{"pmid":"26788540","id":"PMC_26788540","title":"Mid1/Mid2 expression in craniofacial development and a literature review of X-linked opitz syndrome.","date":"2015","source":"Molecular genetics & genomic medicine","url":"https://pubmed.ncbi.nlm.nih.gov/26788540","citation_count":17,"is_preprint":false},{"pmid":"36418932","id":"PMC_36418932","title":"HOXA11-OS participates in lupus nephritis by targeting miR-124-3p mediating Cyr61 to regulate podocyte autophagy.","date":"2022","source":"Molecular medicine (Cambridge, Mass.)","url":"https://pubmed.ncbi.nlm.nih.gov/36418932","citation_count":17,"is_preprint":false},{"pmid":"29450633","id":"PMC_29450633","title":"MID1-PP2A complex functions as new insights in human lung adenocarcinoma.","date":"2018","source":"Journal of cancer research and clinical 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development","url":"https://pubmed.ncbi.nlm.nih.gov/22285438","citation_count":16,"is_preprint":false},{"pmid":"39159848","id":"PMC_39159848","title":"High-Throughput Transcriptomics Screen of ToxCast Chemicals in U-2 OS Cells.","date":"2024","source":"Toxicology and applied pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/39159848","citation_count":15,"is_preprint":false},{"pmid":"35348152","id":"PMC_35348152","title":"Os(II) complexes for catalytic anticancer therapy: recent update.","date":"2022","source":"Chemical communications (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/35348152","citation_count":15,"is_preprint":false},{"pmid":"35331874","id":"PMC_35331874","title":"Tanshinol suppresses osteosarcoma by specifically inducing apoptosis of U2-OS cells through p53-mediated mechanism.","date":"2022","source":"Journal of ethnopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/35331874","citation_count":15,"is_preprint":false},{"pmid":"34894670","id":"PMC_34894670","title":"Reactivity of N-Heterocyclic Carbene Half-Sandwich Ru-, Os-, Rh-, and Ir-Based Complexes with Cysteine and Selenocysteine: A Computational Study.","date":"2021","source":"Inorganic chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/34894670","citation_count":15,"is_preprint":false},{"pmid":"38777113","id":"PMC_38777113","title":"Mid1 promotes synovitis in rheumatoid arthritis via ubiquitin-dependent post-translational modification.","date":"2024","source":"Pharmacological research","url":"https://pubmed.ncbi.nlm.nih.gov/38777113","citation_count":14,"is_preprint":false},{"pmid":"26781309","id":"PMC_26781309","title":"Biological evaluation of 2-arylidene-4, 7-dimethyl indan-1-one (FXY-1): a novel Akt inhibitor with potent activity in lung cancer.","date":"2016","source":"Cancer chemotherapy and pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/26781309","citation_count":14,"is_preprint":false},{"pmid":"22407675","id":"PMC_22407675","title":"A MID1 gene mutation in a patient with Opitz G/BBB syndrome that altered the 3D structure of SPRY domain.","date":"2012","source":"American journal of medical genetics. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/22407675","citation_count":14,"is_preprint":false},{"pmid":"18697196","id":"PMC_18697196","title":"Clinical and molecular studies of patients with characteristics of Opitz G/BBB syndrome shows a novel MID1 mutation.","date":"2008","source":"American journal of medical genetics. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/18697196","citation_count":14,"is_preprint":false},{"pmid":"10694511","id":"PMC_10694511","title":"yam8(+), a Schizosaccharomyces pombe gene, is a potential homologue of the Saccharomyces cerevisiae MID1 gene encoding a stretch-activated Ca(2+)-permeable channel.","date":"2000","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/10694511","citation_count":14,"is_preprint":false},{"pmid":"27367845","id":"PMC_27367845","title":"Solution structure of the microtubule-targeting COS domain of MID1.","date":"2016","source":"The FEBS journal","url":"https://pubmed.ncbi.nlm.nih.gov/27367845","citation_count":14,"is_preprint":false},{"pmid":"25193139","id":"PMC_25193139","title":"Characterization of the Grp94/OS-9 chaperone-lectin complex.","date":"2014","source":"Journal of molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/25193139","citation_count":13,"is_preprint":false},{"pmid":"28141488","id":"PMC_28141488","title":"Protein-protein interactions of the baculovirus per os infectivity factors (PIFs) in the PIF complex.","date":"2017","source":"The Journal of general virology","url":"https://pubmed.ncbi.nlm.nih.gov/28141488","citation_count":13,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":50091,"output_tokens":6122,"usd":0.121052,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":14833,"output_tokens":5459,"usd":0.10532,"stage2_stop_reason":"end_turn"},"total_usd":0.226372,"stage1_batch_id":"msgbatch_01BbTCMyrRPyhtEq6b1MdwCN","stage2_batch_id":"msgbatch_011dEed5bbxYvTAaQWKJevxu","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1999,\n      \"finding\": \"MID1 protein associates with microtubules and influences microtubule dynamics in overexpressing cells; endogenous MID1 co-localizes with tubulin in subcellular fractions and associates with microtubules in an in vitro assembly assay. OS patient mutations abolish microtubule association, causing cytoplasmic aggregation instead.\",\n      \"method\": \"GFP tagging, subcellular fractionation, in vitro microtubule assembly assay, immunofluorescence\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (live imaging, fractionation, in vitro assembly), replicated with patient mutations as controls\",\n      \"pmids\": [\"10077590\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"MID1 and MID2 interact with Alpha 4 (regulatory subunit of PP2-type phosphatases) via their B-box domains; the coiled-coil motifs mediate homo- and heterodimerization, and dimerization is required for association of the MID1/Alpha4 complex with microtubules.\",\n      \"method\": \"Yeast two-hybrid screening, domain-deletion analysis\",\n      \"journal\": \"BMC cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — yeast two-hybrid plus domain mapping, single lab but consistent domain dissection\",\n      \"pmids\": [\"11806752\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"MID1 interacts with Mig12 via its coiled-coil domain; when co-expressed, Mig12 is recruited to thick microtubule bundles by MID1. The MID1-Mig12 complex stabilizes microtubules (bundles are resistant to depolymerizing agents and composed of acetylated tubulin).\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, co-transfection with immunofluorescence, microtubule depolymerization assay\",\n      \"journal\": \"BMC cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP and functional microtubule stabilization assay, single lab\",\n      \"pmids\": [\"15070402\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"MID1 assembles a microtubule-associated ribonucleoprotein complex that includes elongation factor 1α (EF-1α), RACK1, Annexin A2, Nucleophosmin, and small ribosomal subunit proteins; the complex specifically associates with G- and U-rich RNAs and incorporates MID1 mRNA. OS patient mutations in MID1 abolish its interaction with EF-1α.\",\n      \"method\": \"Yeast two-hybrid, immunofluorescence, affinity purification, microtubule assembly co-fractionation, immunoprecipitation, RNA binding assay\",\n      \"journal\": \"Human genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — five independent orthogonal methods in one study confirming the complex and RNA association\",\n      \"pmids\": [\"18172692\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"MID1 undergoes active, bi-directional transport along microtubules dependent on both kinesins and dyneins. Transport is regulated by MAP kinase and PP2A-mediated phosphorylation (simulating permanent phosphorylation at Ser96 stops migration). Knockdown of alpha4, inhibition of PP2A by okadaic acid/fostriecin, or OS patient B-box1 missense mutations block active transport while preserving microtubule association.\",\n      \"method\": \"FRAP (fluorescence recovery after photobleaching), pharmacological inhibition (colcemide, okadaic acid, fostriecin), siRNA knockdown, phosphomimetic mutations\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — FRAP with multiple pharmacological and genetic perturbations, mechanistic dissection of phosphorylation dependence\",\n      \"pmids\": [\"18949047\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"MID1 and its paralog MID2 are required for neural tube closure in Xenopus; MID knockdown destabilizes and disorganizes apicobasally polarized microtubules in the neural plate, disrupting epithelial morphology. MIDs and their interactor Mig12 cooperate for microtubule stabilization during neural plate remodeling.\",\n      \"method\": \"Morpholino-mediated knockdown, immunofluorescence, live imaging of microtubule dynamics\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean loss-of-function with defined cellular and microtubule phenotype, Xenopus ortholog study, single lab\",\n      \"pmids\": [\"20534674\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"MID1 functions as an E3 ligase targeting the catalytic subunit of PP2A (PP2A-C) for ubiquitin-mediated degradation. Elevated PP2A resulting from MID1 depletion or proteasome inhibition disrupts the mTOR/Raptor complex and down-regulates mTORC1 signaling (reduced S6K1 phosphorylation, cell size, cap-dependent translation). This is rescued by wild-type MID1 re-expression or constitutively active mTOR.\",\n      \"method\": \"siRNA knockdown, proteasome inhibition, co-immunoprecipitation, phosphorylation assays, rescue experiments with WT MID1 or activated mTOR, OS patient-derived fibroblasts\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal experiments including patient cells, knockdown, rescue, and co-IP, single lab with mechanistic depth\",\n      \"pmids\": [\"21555591\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Human MID1 RING domain exhibits E3 ubiquitin ligase activity in vitro, catalyzing auto-polyubiquitination; tandem RING-Bbox1 and RING-Bbox1-Bbox2 constructs show greater activity than individual domains. MID1 facilitates Lys63-linked ubiquitin chain elongation and polyubiquitinates its Bbox1 domain at Lys154. A C-terminal peptide of alpha4 that binds Bbox1 is monoubiquitinated and inhibits polyubiquitin product formation.\",\n      \"method\": \"In vitro E3 ligase assay, ubiquitin linkage mutants, mass spectrometry, domain mutagenesis\",\n      \"journal\": \"Journal of molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with mutagenesis and mass spectrometry, single lab\",\n      \"pmids\": [\"21296087\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Expanded CAG repeat RNA (from huntingtin and other polyglutamine disease genes) binds to a complex containing MID1, PP2A, and 40S ribosomal S6 kinase. Binding increases with CAG repeat length and stimulates translation of the repeat-containing mRNA in a MID1-, PP2A-, and mTOR-dependent manner.\",\n      \"method\": \"RNA immunoprecipitation, co-immunoprecipitation, translation reporter assays, siRNA knockdown\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal biochemical and functional assays establishing both the complex composition and translational output\",\n      \"pmids\": [\"23443539\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"MID1-dependent PP2Ac turnover is required for normal axon development; silencing Mid1 increases PP2Ac levels, promoting axon growth and branching and disrupting callosal projections in vivo. Further knockdown of PP2Ac rescues the axonal phenotype in Mid1-depleted neurons.\",\n      \"method\": \"In vitro knockdown, Mid1 knockout mouse, in vivo brain imaging, genetic epistasis (double knockdown of Mid1 and PP2Ac)\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vitro and in vivo loss-of-function with genetic rescue epistasis establishing pathway position\",\n      \"pmids\": [\"24194544\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"MID1 E3 ligase catalyzes polyubiquitination of alpha4 (regulatory subunit of PP2A); direct binding of alpha4 to the Bbox1 domain is required (a L146Q mutation abolishes alpha4 interaction and its polyubiquitination without affecting RING autoubiquitination). Full-length MID1 and RING-Bbox1 constructs catalyze alpha4 polyubiquitination; ubiquitination of alpha4 occurs within its last 105 amino acids.\",\n      \"method\": \"In vitro ubiquitination assay, dominant-negative MID1 stable cells, proteasome inhibition, mass spectrometry, mutagenesis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with mutagenesis, mass spectrometry, and cell-based validation, mechanistically rigorous\",\n      \"pmids\": [\"23740247\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"MID1 protein complex associates with androgen receptor (AR) mRNA via purine-rich trinucleotide repeats and increases AR protein levels through enhanced translation (without changing mRNA levels or AR protein stability). Conversely, AR exerts a negative transcriptional feedback on MID1 via AR binding sites in the MID1 gene.\",\n      \"method\": \"Co-immunoprecipitation followed by PCR, RNA pull-down followed by western blot, siRNA knockdown, overexpression, reporter gene assays, chromatin immunoprecipitation\",\n      \"journal\": \"Molecular cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNA pull-down, Co-IP-PCR, and functional rescue in single lab, multiple methods\",\n      \"pmids\": [\"24913494\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"MID1 E3 ligase catalyzes ubiquitination and proteasomal cleavage of Fu (Fused kinase), a regulator of GLI3 transcriptional activity in the SHH-GLI signaling pathway, linking the MID1-PP2A complex to GLI3 activity control.\",\n      \"method\": \"In vitro ubiquitination assay, co-immunoprecipitation, proteasome inhibition, cell-based reporter assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro ubiquitination combined with cell-based epistasis, single lab\",\n      \"pmids\": [\"25278022\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"MID1 catalyzes in vitro ubiquitination of the PP2A catalytic subunit (PP2Ac) directly, in the absence of alpha4. In the presence of alpha4, PP2Ac ubiquitination is reduced. OS patient Bbox1 domain mutations (C142S, C145T, A130V/T) abolish polyubiquitination of alpha4 but not of PP2Ac, suggesting alpha4 dysregulation as the direct molecular consequence of these mutations.\",\n      \"method\": \"In vitro ubiquitination assay, domain mutagenesis, western blot\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with mutagenesis, single lab\",\n      \"pmids\": [\"25207814\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Metformin decreases BACE1 protein expression by interfering with the MID1 mRNA-protein complex, reducing BACE1 activity in primary neurons, human cell lines, and in vivo in mice.\",\n      \"method\": \"Western blot, pharmacological treatment, siRNA knockdown, in vivo mouse studies\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — convergent in vitro and in vivo evidence, single lab, mechanism linked to MID1 complex\",\n      \"pmids\": [\"25025689\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"NMR solution structure of the MID1 COS (C-terminal subgroup One Signature) domain reveals a helix-loop-helix fold with a hydrophobic core and a basic patch of positively charged residues. Fusion of the COS domain to the coiled-coil (CC) domain confers microtubule binding; CC-COS constructs directly bind microtubules, establishing the structural basis for MID1 microtubule association.\",\n      \"method\": \"NMR structure determination (PDB: 5IM8), microtubule binding assay, domain fusion experiments\",\n      \"journal\": \"The FEBS journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — NMR structure with functional microtubule binding validation, single lab\",\n      \"pmids\": [\"27367845\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"MID1 protein complex binds to ATXN2, ATXN3, and ATXN7 mRNAs in a CAG repeat length-dependent manner and induces protein synthesis of the cognate polyglutamine proteins in a repeat length-dependent manner, indicating a common translational regulatory mechanism for expanded CAG repeat mRNAs.\",\n      \"method\": \"RNA immunoprecipitation, translation reporter assays, western blot, siRNA knockdown\",\n      \"journal\": \"Frontiers in cellular neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — consistent biochemical and functional assays across multiple substrates, single lab\",\n      \"pmids\": [\"27774050\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Resveratrol decreases MID1 ubiquitin ligase expression, which reduces MID1-mediated ubiquitination and degradation of PP2A-C on microtubules, thereby increasing PP2A activity and reducing Tau phosphorylation at PP2A-dependent epitopes. MID1 expression is elevated in Alzheimer's disease tissue.\",\n      \"method\": \"Western blot, PP2A activity assay, phospho-tau immunoblot, pharmacological treatment with resveratrol\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pharmacological perturbation linked mechanistically to MID1 level change, with biochemical readouts, single lab\",\n      \"pmids\": [\"29062069\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Mid1 levels are reduced in Rac1/Rac3 double-knockout cerebellar granule neurons, and Mid1 depletion impairs neuritogenesis and reduces mTORC1 signaling, placing Mid1 downstream of Rac GTPases and upstream of mTORC1 in a Rac1-Mid1-mTORC1 pathway in cerebellar development.\",\n      \"method\": \"Conditional double knockout mouse, Mid1 siRNA depletion in primary neurons, mTORC1 signaling western blot, neurite morphology assay\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic double KO with epistasis supported by siRNA, single lab\",\n      \"pmids\": [\"28512198\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"MID1 protein complex binds to and regulates translation of APP mRNA via the mTOR pathway; inhibition of the MID1 complex by metformin reduces APP protein levels and Aβ in an AD mouse model when treatment is initiated in an already-advanced disease state.\",\n      \"method\": \"RNA immunoprecipitation, western blot, mTOR pathway inhibition, primary neuron cultures, in vivo mouse treatment, behavioral phenotype\",\n      \"journal\": \"Cell death discovery\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro mRNA binding plus in vivo intervention, single lab, builds on established MID1-mTOR axis\",\n      \"pmids\": [\"29531801\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"TRAIL signals through the MID1 ubiquitin ligase to deactivate PP2A, promoting pulmonary fibrosis; TRAIL-deficient mice and PP2A activator-treated mice are protected from bleomycin-induced fibrosis. Recombinant TRAIL increases collagen production in fibroblasts, reversible by PP2A activation.\",\n      \"method\": \"Genetic TRAIL-knockout mouse, pharmacological PP2A activation, in vitro fibroblast treatment, lung function measurement, human biopsy analysis\",\n      \"journal\": \"BMC pulmonary medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo genetic and pharmacological experiments with in vitro corroboration, single lab\",\n      \"pmids\": [\"30732588\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MID1 physically interacts with IRF3, induces K48-linked polyubiquitination of IRF3 at Lys313, and promotes proteasomal degradation of IRF3, thereby restricting type I interferon production and cellular antiviral response.\",\n      \"method\": \"Co-immunoprecipitation, in vitro/cellular ubiquitination assay, site-directed mutagenesis of ubiquitin acceptor site, IFN reporter assay, antiviral assay\",\n      \"journal\": \"Immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, ubiquitination assay with K48-linkage specificity, lysine mutagenesis, and functional IFN output, multiple orthogonal methods\",\n      \"pmids\": [\"33513265\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"TRIM18 (MID1) recruits protein phosphatase PPM1A to dephosphorylate TBK1, inactivating TBK1 and blocking its interaction with MAVS and STING adaptors, thereby dampening antiviral interferon signaling. TRIM18 also stabilizes PPM1A by inducing K63-linked ubiquitination of PPM1A.\",\n      \"method\": \"Co-immunoprecipitation, immunoblot, siRNA knockdown, TRIM18 knockout mice with viral challenge, luciferase assay, ubiquitination assay\",\n      \"journal\": \"Journal of biomedical science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — Co-IP, in vivo KO with viral challenge, ubiquitination assay, multiple orthogonal methods across in vitro and in vivo models\",\n      \"pmids\": [\"35909127\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TRIM18 (MID1) promotes ubiquitin-mediated proteasomal degradation of PTP1B, which activates STAT3 signaling to promote renal epithelial-mesenchymal transition, inflammation, and fibrosis in diabetic kidney disease.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, western blot, siRNA knockdown, overexpression in HK-2 cells, pharmacological STAT3 inhibition\",\n      \"journal\": \"Frontiers in physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, ubiquitination assay, and epistasis via PTP1B/STAT3 rescue, single lab\",\n      \"pmids\": [\"34434118\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MID1 promotes synoviocyte proliferation and migration by inducing ubiquitin-mediated proteasomal degradation of DPP4; DPP4 deficiency phenocopies MID1 overexpression and DPP4 reconstitution abolishes MID1-induced synoviocyte activation. In a collagen-induced arthritis model, Mid1 knockout completely protects mice from arthritis, and this protection is abolished by concurrent DPP4 knockout.\",\n      \"method\": \"Co-immunoprecipitation, proteomic analysis, ubiquitination assay, overexpression/knockdown in synoviocytes, collagen-induced arthritis in Mid1-/- and Mid1-/-Dpp4-/- double-knockout mice\",\n      \"journal\": \"Pharmacological research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — Co-IP, ubiquitination assay, in vivo double-KO epistasis, and functional rescue with DPP4 reconstitution\",\n      \"pmids\": [\"38777113\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MID1 (TRIM18) is a microtubule-associated RING-Bbox-coiled-coil E3 ubiquitin ligase that assembles a large microtubule-anchored complex containing the PP2A catalytic subunit (PP2Ac), its regulatory subunit alpha4 (α4), translation factors (EF-1α, RACK1, ribosomal subunits), and specific mRNAs; it ubiquitinates PP2Ac (via K48-linked chains, targeted by alpha4 interaction through the Bbox1 domain), alpha4, DPP4, IRF3, Fu kinase, and PPM1A (K63-linked), thereby controlling PP2A activity, mTORC1 signaling, cap-dependent translation of target mRNAs (including CAG-repeat-containing mRNAs, AR mRNA, and APP mRNA), SHH-GLI and innate immune (TBK1-IFN) signaling pathways; the protein is actively transported along microtubules in a PP2A/alpha4/mTOR phosphorylation-dependent manner, and its COS domain directly mediates microtubule binding.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"MID1 (TRIM18) is a microtubule-associated RING-Bbox-coiled-coil E3 ubiquitin ligase that couples microtubule dynamics to phosphatase control, protein translation, and signaling, with loss-of-function disrupting epithelial and neuronal microtubule architecture during development [#0, #5, #15]. It binds microtubules directly through a helix-loop-helix COS domain acting in concert with the coiled-coil region, while coiled-coil-mediated dimerization is required for the assembled complex to associate with microtubules [#15, #1]; the protein is actively transported bidirectionally along microtubules by kinesins and dyneins in a manner gated by MAP kinase and PP2A-dependent phosphorylation [#4]. The central biochemical activity of MID1 is RING-dependent ubiquitination, in which the Bbox1 domain recruits the PP2A regulatory subunit alpha4, and MID1 ubiquitinates both alpha4 and the PP2A catalytic subunit (PP2Ac) to drive their proteasomal turnover and thereby raise net PP2A activity when MID1 is lost [#7, #10, #13, #6]. By limiting PP2A, MID1 sustains mTORC1 signaling and cap-dependent translation, positioning it downstream of Rac GTPases and upstream of mTORC1 in neuronal morphogenesis and axon development [#6, #18, #9]. MID1 also nucleates a microtubule-anchored ribonucleoprotein complex with EF-1\\u03b1, RACK1, and ribosomal subunits that binds purine-rich and CAG-repeat-containing mRNAs and stimulates their translation in a PP2A/mTOR-dependent manner, including expanded CAG-repeat polyglutamine transcripts, androgen receptor mRNA, and APP mRNA [#3, #8, #16, #11, #19]. Beyond PP2A, MID1 ubiquitinates additional substrates to control distinct pathways: Fused kinase in SHH-GLI signaling [#12], IRF3 (K48-linked) and PPM1A (K63-linked) to restrain type I interferon and TBK1-dependent antiviral signaling [#21, #22], and DPP4 and PTP1B in inflammatory and fibrotic disease contexts [#24, #23]. Patient mutations in MID1 cause Opitz syndrome by abolishing microtubule association or, for Bbox1 mutations, selectively disrupting alpha4 binding and ubiquitination [#0, #13].\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Established MID1 as a microtubule-associated protein whose disease mutations mislocalize it, defining microtubules as its primary site of action.\",\n      \"evidence\": \"GFP tagging, subcellular fractionation, and in vitro microtubule assembly with patient mutation controls\",\n      \"pmids\": [\"10077590\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify the domain mediating microtubule binding\", \"No molecular partners defined\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Identified alpha4 (PP2-type phosphatase regulatory subunit) as a Bbox-binding partner and showed coiled-coil dimerization is required for microtubule association, linking MID1 to phosphatase regulation.\",\n      \"evidence\": \"Yeast two-hybrid and domain-deletion analysis\",\n      \"pmids\": [\"11806752\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No demonstration of catalytic consequence on PP2A\", \"Single-lab Y2H without reciprocal in vivo validation\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Showed MID1 recruits Mig12 to stabilize and bundle microtubules, defining a functional role in microtubule stabilization.\",\n      \"evidence\": \"Yeast two-hybrid, reciprocal Co-IP, and microtubule depolymerization assays\",\n      \"pmids\": [\"15070402\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of bundle stabilization unresolved\", \"Physiological context not established\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Revealed MID1 assembles a microtubule-anchored ribonucleoprotein complex binding G/U-rich RNAs, extending its function from cytoskeleton to translation, with OS mutations disrupting EF-1\\u03b1 binding.\",\n      \"evidence\": \"Affinity purification, co-fractionation, RNA-binding, and Y2H across five orthogonal methods\",\n      \"pmids\": [\"18172692\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Translational output of the complex not yet measured\", \"RNA target specificity beyond MID1 mRNA undefined\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Demonstrated MID1 is actively transported along microtubules by motors in a phosphorylation-gated manner, mechanistically connecting PP2A/alpha4 to MID1 trafficking.\",\n      \"evidence\": \"FRAP with pharmacological PP2A inhibition, siRNA, and phosphomimetic mutations\",\n      \"pmids\": [\"18949047\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Kinase responsible for Ser96 phosphorylation in vivo not defined\", \"Functional purpose of transport unclear\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Defined MID1 as an E3 ligase that degrades PP2A-C to sustain mTORC1 signaling and cap-dependent translation, establishing the core MID1-PP2A-mTOR axis.\",\n      \"evidence\": \"siRNA, proteasome inhibition, Co-IP, rescue with WT MID1 or activated mTOR, and OS patient fibroblasts\",\n      \"pmids\": [\"21555591\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Ubiquitin linkage type on PP2Ac not specified here\", \"Direct vs alpha4-bridged targeting not resolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Reconstituted MID1 RING ligase activity in vitro, showing tandem RING-Bbox cooperation, K63 chain elongation, and Bbox1 autoubiquitination at Lys154.\",\n      \"evidence\": \"In vitro ligase assays with linkage mutants, mass spectrometry, and domain mutagenesis\",\n      \"pmids\": [\"21296087\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological substrate beyond autoubiquitination not addressed here\", \"E2 enzyme partner in cells undefined\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Identified alpha4 and PP2Ac as direct MID1 substrates, mapping alpha4 ubiquitination to Bbox1-dependent recruitment and explaining how OS Bbox1 mutations dysregulate the complex.\",\n      \"evidence\": \"In vitro ubiquitination, dominant-negative cell lines, mass spectrometry, and mutagenesis (#10, #13)\",\n      \"pmids\": [\"23740247\", \"25207814\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Relative in vivo contribution of alpha4 vs PP2Ac ubiquitination unresolved\", \"Stoichiometry of alpha4-PP2Ac-MID1 complex undefined\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Connected expanded CAG-repeat RNA to the MID1-PP2A-S6K complex and showed length-dependent stimulation of repeat-mRNA translation, linking MID1 to polyglutamine disease pathology.\",\n      \"evidence\": \"RNA immunoprecipitation, Co-IP, translation reporters, and siRNA\",\n      \"pmids\": [\"23443539\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct RNA-binding subunit within the complex not pinpointed\", \"In vivo relevance to disease onset not tested\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Established the physiological requirement for MID1-dependent PP2Ac turnover in axon development via genetic epistasis in vivo.\",\n      \"evidence\": \"Mid1 knockout mouse, in vivo brain imaging, and Mid1/PP2Ac double-knockdown rescue\",\n      \"pmids\": [\"24194544\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Downstream effectors of PP2A in axon growth not defined\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Extended MID1 translational control to disease-relevant mRNAs (AR, APP) and to substrate Fu kinase in SHH-GLI signaling, broadening its regulatory reach.\",\n      \"evidence\": \"RNA pull-down, Co-IP-PCR, reporter assays, ChIP, and in vitro ubiquitination (#11, #12, #14)\",\n      \"pmids\": [\"24913494\", \"25278022\", \"25025689\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Sequence determinants of mRNA target selection incompletely mapped\", \"Single-lab evidence for each target\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Solved the COS domain structure and demonstrated CC-COS suffices for direct microtubule binding, providing the structural basis for MID1 cytoskeletal anchoring.\",\n      \"evidence\": \"NMR structure (PDB 5IM8) with microtubule-binding domain fusion assays\",\n      \"pmids\": [\"27367845\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tubulin contact residues not mapped\", \"Structure of full-length assembled complex unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Generalized the CAG-repeat translational mechanism across ataxin transcripts, establishing a common MID1 pathway for multiple polyglutamine diseases.\",\n      \"evidence\": \"RNA immunoprecipitation, translation reporters, and siRNA across ATXN2/3/7\",\n      \"pmids\": [\"27774050\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vivo confirmation across disease models lacking\", \"Single-lab functional series\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Placed Mid1 downstream of Rac GTPases and upstream of mTORC1 in neuronal development and linked MID1-PP2A-Tau regulation to Alzheimer's disease pathology.\",\n      \"evidence\": \"Rac1/Rac3 double-knockout mice, siRNA, mTORC1 immunoblot, PP2A activity and phospho-Tau assays (#17, #18)\",\n      \"pmids\": [\"28512198\", \"29062069\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting Rac to MID1 expression undefined\", \"Causal role in human AD not established\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Identified TRAIL as an upstream input that signals through MID1 to deactivate PP2A, implicating the axis in pulmonary fibrosis.\",\n      \"evidence\": \"TRAIL-knockout mice, PP2A activator treatment, fibroblast assays, and human biopsies\",\n      \"pmids\": [\"30732588\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct biochemical link from TRAIL receptor to MID1 not defined\", \"Single-lab disease model\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined MID1/TRIM18 as a negative regulator of antiviral signaling through K48 degradation of IRF3 and PPM1A-mediated TBK1 dephosphorylation, with K63 stabilization of PPM1A.\",\n      \"evidence\": \"Reciprocal Co-IP, linkage-specific ubiquitination assays, lysine mutagenesis, IFN reporters, and TRIM18-knockout mice with viral challenge (#21, #22)\",\n      \"pmids\": [\"33513265\", \"35909127\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Integration with microtubule/PP2A functions unclear\", \"Cell-type specificity of immune restriction not mapped\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrated MID1-driven degradation of DPP4 (and PTP1B/STAT3 in kidney disease) as a mechanism in inflammatory and fibrotic pathology, validated by in vivo double-knockout epistasis.\",\n      \"evidence\": \"Co-IP, proteomics, ubiquitination assays, and Mid1-/-Dpp4-/- collagen-induced arthritis mice with DPP4 reconstitution (#23, #24)\",\n      \"pmids\": [\"38777113\", \"34434118\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether DPP4/PTP1B targeting depends on the alpha4/PP2A machinery unknown\", \"Substrate recognition determinants undefined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how MID1 selects among its diverse substrates (PP2Ac, alpha4, IRF3, PPM1A, DPP4, PTP1B, Fu) and target mRNAs, and how microtubule anchoring, motor transport, ubiquitination, and translational control are integrated within a single complex.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified structural model of the assembled MID1 complex\", \"Substrate-selection code unknown\", \"Mechanism coupling RNA binding to ligase activity undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [6, 7, 10, 13, 21, 22, 23, 24]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [6, 10, 12, 13, 21, 22, 24]},\n      {\"term_id\": \"GO:0003723\", \"supporting_discovery_ids\": [3, 8, 11, 16, 19]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [0, 2, 15]},\n      {\"term_id\": \"GO:0045182\", \"supporting_discovery_ids\": [8, 11, 16, 19]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [0, 2, 4, 15]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [6, 7, 10, 13, 21, 22, 24]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [6, 12, 18, 20, 22, 23]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [21, 22]},\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [3, 8, 11, 16, 19]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [5, 9, 18]}\n    ],\n    \"complexes\": [\n      \"MID1-alpha4-PP2A complex\",\n      \"MID1 microtubule-associated ribonucleoprotein complex\"\n    ],\n    \"partners\": [\n      \"PPP2CA\",\n      \"IGBP1\",\n      \"MID2\",\n      \"Mig12\",\n      \"EEF1A\",\n      \"RACK1\",\n      \"IRF3\",\n      \"PPM1A\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}