{"gene":"MKLN1","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":1999,"finding":"Human muskelin (MKLN1) is an intracellular protein that acts as a mediator of cell spreading and cytoskeletal responses to the extracellular matrix component thrombospondin-1; the human gene was cloned and localized to chromosome 7q32.","method":"cDNA cloning, physical mapping, FISH","journal":"Cytogenetics and cell genetics","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — cDNA cloning and localization; functional role in cell spreading/cytoskeletal response attributed from earlier mouse studies referenced in the abstract, not newly demonstrated here","pmids":["10640805"],"is_preprint":false},{"year":2018,"finding":"A splice-region variant in MKLN1 (c.400+3A>C) causes exon 4 skipping and a reading-frame shift, leading to lethal acrodermatitis (LAD) in Bull Terriers, demonstrating that loss of functional MKLN1 protein causes a disease phenotype involving poor growth, immune deficiency, and skin lesions.","method":"Genome-wide association study, haplotype analysis, whole-genome sequencing, RT-PCR of skin RNA from affected vs. control dogs","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — GWAS mapping + perfect case-control association (46 cases, 294 controls) + RT-PCR confirmation of aberrant splicing; multiple orthogonal methods in one study","pmids":["29565995"],"is_preprint":false},{"year":2024,"finding":"MKLN1 protein (together with ZMYND19) accumulates upon CTLH E3 ligase (MAEA subunit) knockout, associates with lysosome outer membranes, binds Raptor and RagA/C, and blocks a late step of mTORC1 activation by disrupting mTORC1 interaction with Rheb and with mTORC1 substrates S6K and 4E-BP1, independently of the tuberous sclerosis complex; CTLH-mediated ubiquitin/proteasome degradation of MKLN1 thus tunes mTORC1 activity.","method":"Genome-wide CRISPR/Cas9 screen, MAEA knockout, co-immunoprecipitation (MKLN1/ZMYND19/Raptor/RagA/C), lysosomal fractionation, mTORC1 activity assays, proteasome inhibitor treatment","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, subcellular fractionation, CRISPR KO with defined pathway phenotype, multiple orthogonal methods; peer-reviewed replication of preprint findings","pmids":["41315365","38746323"],"is_preprint":false},{"year":2025,"finding":"MKLN1 is required for assembly of CTLH-MKLN1 E3 ubiquitin ligase complexes (distinct from CTLH-WDR26 assemblies); Mkln1-/- mice show reduced somatic hypermutation and class switch recombination due to increased UNG2 levels, and display increased germinal center B cells and B-cell developmental defects, indicating that CTLH-MKLN1 complexes regulate substrates beyond FAM72A.","method":"Mkln1-/- mouse genetic knockout, flow cytometry of B-cell populations, somatic hypermutation frequency assay, class switch recombination assay, UNG2 protein level measurement","journal":"Journal of immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic KO with multiple specific cellular phenotype readouts (SHM, CSR, B-cell development) and protein-level mechanistic link to UNG2 accumulation","pmids":["40838616"],"is_preprint":false}],"current_model":"MKLN1 encodes muskelin, an intracellular protein that (1) mediates cell spreading and cytoskeletal responses to thrombospondin-1, (2) assembles into CTLH-MKLN1 E3 ubiquitin ligase complexes that target UNG2 degradation to support B-cell antibody diversification, and (3) acts—when not degraded by the CTLH complex—as a negative regulator of mTORC1 at the lysosomal membrane by associating with ZMYND19, binding Raptor and RagA/C, and blocking mTORC1 interaction with Rheb and its substrates; loss-of-function of MKLN1 in dogs causes a lethal genodermatosis (LAD) via exon-skipping and frameshift mutation."},"narrative":{"mechanistic_narrative":"MKLN1 encodes muskelin, an intracellular adaptor protein that integrates cytoskeletal, ubiquitin-ligase, and growth-signaling functions [PMID:10640805, PMID:41315365, PMID:38746323]. Originally identified as a mediator of cell spreading and cytoskeletal responses to the extracellular matrix component thrombospondin-1 [PMID:10640805], muskelin is now established as a substrate and assembly factor of the CTLH E3 ubiquitin ligase: MKLN1 is required for the formation of CTLH-MKLN1 complexes (distinct from CTLH-WDR26 assemblies), and these complexes target UNG2 for degradation to support antibody diversification, since Mkln1-deficient mice show reduced somatic hypermutation and class switch recombination from UNG2 accumulation alongside altered germinal-center and developmental B-cell populations [PMID:40838616]. When not degraded by the CTLH complex, MKLN1 accumulates at the lysosomal outer membrane together with ZMYND19, binds Raptor and RagA/C, and blocks a late step of mTORC1 activation by disrupting mTORC1 interaction with Rheb and with its substrates S6K and 4E-BP1, independently of the tuberous sclerosis complex—so CTLH-mediated degradation of MKLN1 tunes mTORC1 activity [PMID:41315365, PMID:38746323]. Loss-of-function of MKLN1 via a splice variant causing exon skipping and frameshift produces lethal acrodermatitis, a genodermatosis with poor growth, immune deficiency, and skin lesions [PMID:29565995].","teleology":[{"year":1999,"claim":"Established the first functional identity of human muskelin by cloning the gene and linking it to cytoskeletal responses to the extracellular matrix.","evidence":"cDNA cloning, physical mapping, and FISH localization to chromosome 7q32","pmids":["10640805"],"confidence":"Medium","gaps":["Cell-spreading/cytoskeletal function attributed from prior mouse work, not newly demonstrated here","No molecular partners or biochemical mechanism defined","No connection to ubiquitin ligase or mTORC1 functions"]},{"year":2018,"claim":"Demonstrated that loss of functional MKLN1 causes disease, defining an in vivo requirement for the protein in growth, immunity, and skin integrity.","evidence":"GWAS, haplotype analysis, whole-genome sequencing, and RT-PCR confirmation of exon-4 skipping in affected vs. control dogs (lethal acrodermatitis)","pmids":["29565995"],"confidence":"High","gaps":["Molecular mechanism connecting MKLN1 loss to the skin/immune phenotype not resolved","Did not identify MKLN1 protein partners or pathway","Phenotype defined in dogs; human disease relevance not addressed"]},{"year":2024,"claim":"Defined a signaling mechanism: MKLN1 is a CTLH ligase substrate that, when stabilized, acts as a lysosomal negative regulator of mTORC1.","evidence":"Genome-wide CRISPR screen, MAEA knockout, reciprocal Co-IP (MKLN1/ZMYND19/Raptor/RagA/C), lysosomal fractionation, mTORC1 activity assays, and proteasome inhibition","pmids":["41315365","38746323"],"confidence":"High","gaps":["Structural basis for how MKLN1/ZMYND19 occlude Rheb and substrate access not resolved","Physiological conditions that trigger MKLN1 stabilization vs. degradation not defined","Role of the ancestral thrombospondin/cytoskeletal function in this pathway unaddressed"]},{"year":2025,"claim":"Established MKLN1 as an obligate assembly factor for a distinct CTLH-MKLN1 ligase that controls antibody diversification through UNG2 turnover.","evidence":"Mkln1-/- mice with flow cytometry of B-cell populations, somatic hypermutation and class switch recombination assays, and UNG2 protein-level measurement","pmids":["40838616"],"confidence":"High","gaps":["Full substrate repertoire of CTLH-MKLN1 beyond UNG2 and FAM72A not enumerated","Molecular determinants distinguishing CTLH-MKLN1 from CTLH-WDR26 assemblies not defined","Link between this ligase function and the mTORC1-regulatory pool of MKLN1 not integrated"]},{"year":null,"claim":"How MKLN1's distinct roles—cytoskeletal/thrombospondin response, CTLH-MKLN1 ligase assembly, and lysosomal mTORC1 regulation—are coordinated within a cell remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No structural model unifying its adaptor functions","Conditions partitioning MKLN1 between ligase assembly and degradation unknown","Mechanistic basis of the original cytoskeletal/thrombospondin role uncharacterized in the available corpus"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[3]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[2,3]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[2]}],"localization":[{"term_id":"GO:0005764","term_label":"lysosome","supporting_discovery_ids":[2]}],"pathway":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[2]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[3]}],"complexes":["CTLH-MKLN1 E3 ubiquitin ligase complex"],"partners":["ZMYND19","RPTOR","RRAGA","RRAGC","MAEA"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9UL63","full_name":"Muskelin","aliases":[],"length_aa":735,"mass_kda":84.8,"function":"Component of the CTLH E3 ubiquitin-protein ligase complex that selectively accepts ubiquitin from UBE2H and mediates ubiquitination and subsequent proteasomal degradation of the transcription factor HBP1 (PubMed:29911972). Required for internalization of the GABA receptor GABRA1 from the cell membrane via endosomes and subsequent GABRA1 degradation (By similarity). Acts as a mediator of cell spreading and cytoskeletal responses to the extracellular matrix component THBS1 (PubMed:18710924)","subcellular_location":"Cytoplasm; Cytoplasm, cytosol; Nucleus, nucleoplasm; Cell projection, ruffle; Cytoplasm, cell cortex; Synapse; Postsynapse","url":"https://www.uniprot.org/uniprotkb/Q9UL63/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MKLN1","classification":"Not Classified","n_dependent_lines":25,"n_total_lines":1208,"dependency_fraction":0.020695364238410598},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"RANBP9","stoichiometry":10.0},{"gene":"RANBP10","stoichiometry":4.0}],"url":"https://opencell.sf.czbiohub.org/search/MKLN1","total_profiled":1310},"omim":[{"mim_id":"611625","title":"GID COMPLEX, SUBUNIT 8; GID8","url":"https://www.omim.org/entry/611625"},{"mim_id":"605623","title":"MUSKELIN 1; MKLN1","url":"https://www.omim.org/entry/605623"},{"mim_id":"603854","title":"RAN-BINDING PROTEIN 9; RANBP9","url":"https://www.omim.org/entry/603854"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Plasma membrane","reliability":"Approved"},{"location":"Cytosol","reliability":"Approved"},{"location":"Vesicles","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/MKLN1"},"hgnc":{"alias_symbol":["TWA2"],"prev_symbol":[]},"alphafold":{"accession":"Q9UL63","domains":[{"cath_id":"2.60.120.260","chopping":"15-157","consensus_level":"high","plddt":93.4156,"start":15,"end":157},{"cath_id":"-","chopping":"170-205","consensus_level":"medium","plddt":93.7328,"start":170,"end":205},{"cath_id":"-","chopping":"207-245_629-733","consensus_level":"high","plddt":90.9417,"start":207,"end":733},{"cath_id":"-","chopping":"247-277_505-566_580-625","consensus_level":"medium","plddt":84.6328,"start":247,"end":625},{"cath_id":"2.120.10.80","chopping":"330-414_423-504","consensus_level":"medium","plddt":92.5505,"start":330,"end":504}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UL63","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UL63-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UL63-F1-predicted_aligned_error_v6.png","plddt_mean":89.06},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MKLN1","jax_strain_url":"https://www.jax.org/strain/search?query=MKLN1"},"sequence":{"accession":"Q9UL63","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9UL63.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9UL63/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UL63"}},"corpus_meta":[{"pmid":"33000222","id":"PMC_33000222","title":"Long non‑coding RNA MKLN1‑AS aggravates hepatocellular carcinoma progression by functioning as a molecular sponge for miR‑654‑3p, thereby promoting hepatoma‑derived growth factor expression.","date":"2020","source":"International journal of molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/33000222","citation_count":46,"is_preprint":false},{"pmid":"29565995","id":"PMC_29565995","title":"MKLN1 splicing defect in dogs with lethal acrodermatitis.","date":"2018","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/29565995","citation_count":21,"is_preprint":false},{"pmid":"35138470","id":"PMC_35138470","title":"SOX9/MKLN1-AS Axis Induces Hepatocellular Carcinoma Proliferation and Epithelial-Mesenchymal Transition.","date":"2022","source":"Biochemical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/35138470","citation_count":20,"is_preprint":false},{"pmid":"37549719","id":"PMC_37549719","title":"The circRNA MKLN1 regulates autophagy in the development of diabetic retinopathy.","date":"2023","source":"Biochimica et biophysica acta. Molecular basis of disease","url":"https://pubmed.ncbi.nlm.nih.gov/37549719","citation_count":17,"is_preprint":false},{"pmid":"38740637","id":"PMC_38740637","title":"MKLN1-AS promotes pancreatic cancer progression as a crucial downstream mediator of HIF-1α through miR-185-5p/TEAD1 pathway.","date":"2024","source":"Cell biology and toxicology","url":"https://pubmed.ncbi.nlm.nih.gov/38740637","citation_count":10,"is_preprint":false},{"pmid":"10640805","id":"PMC_10640805","title":"cDNA cloning of human muskelin and localisation of the muskelin (MKLN1) gene to human chromosome 7q32 and mouse chromosome 6 B1/B2 by physical mapping and FISH.","date":"1999","source":"Cytogenetics and cell genetics","url":"https://pubmed.ncbi.nlm.nih.gov/10640805","citation_count":9,"is_preprint":false},{"pmid":"38460002","id":"PMC_38460002","title":"Circular RNA MKLN1 promotes epithelial-mesenchymal transition in pulmonary fibrosis by regulating the miR-26a/b-5p/CDK8 axis in human alveolar epithelial cells and mice models.","date":"2024","source":"Archives of toxicology","url":"https://pubmed.ncbi.nlm.nih.gov/38460002","citation_count":4,"is_preprint":false},{"pmid":"40838616","id":"PMC_40838616","title":"MKLN1-dependent GID4/CTLH E3 ubiquitin ligase complex assemblies are required to support B-cell antibody diversification.","date":"2025","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/40838616","citation_count":3,"is_preprint":false},{"pmid":"34961410","id":"PMC_34961410","title":"Circ-MKLN1/miR-377-3p/CTGF Axis Regulates the TGF-β2-induced Posterior Capsular Opacification in SRA01/04 Cells.","date":"2021","source":"Current eye research","url":"https://pubmed.ncbi.nlm.nih.gov/34961410","citation_count":3,"is_preprint":false},{"pmid":"38746323","id":"PMC_38746323","title":"The CTLH Ubiquitin Ligase Substrates ZMYND19 and MKLN1 Negatively Regulate mTORC1 at the Lysosomal Membrane.","date":"2024","source":"Research square","url":"https://pubmed.ncbi.nlm.nih.gov/38746323","citation_count":3,"is_preprint":false},{"pmid":"41315365","id":"PMC_41315365","title":"The CTLH ubiquitin ligase substrates ZMYND19 and MKLN1 negatively regulate mTORC1 at the lysosomal membrane.","date":"2025","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/41315365","citation_count":2,"is_preprint":false},{"pmid":"39680098","id":"PMC_39680098","title":"LncRNA MKLN1-AS promotes glioma tumorigenesis and growth via activating the Hippo pathway through miR-126-5p/TEAD1 axis.","date":"2024","source":"Naunyn-Schmiedeberg's archives of pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/39680098","citation_count":1,"is_preprint":false},{"pmid":"39647744","id":"PMC_39647744","title":"Molecular mechanism of RB progression and Circ_0082415 inhibits MKLN1 translation to suppress retinoblastoma progression: Changes in mRNA and protein levels.","date":"2024","source":"International journal of biological macromolecules","url":"https://pubmed.ncbi.nlm.nih.gov/39647744","citation_count":1,"is_preprint":false},{"pmid":"40369569","id":"PMC_40369569","title":"Identification of MMP14 and MKLN1 as colorectal cancer susceptibility genes and drug-repositioning candidates from a genome-wide association study.","date":"2025","source":"Journal of translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/40369569","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":9617,"output_tokens":1301,"usd":0.024183,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7896,"output_tokens":2319,"usd":0.048727,"stage2_stop_reason":"end_turn"},"total_usd":0.07291,"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\": \"Human muskelin (MKLN1) is an intracellular protein that acts as a mediator of cell spreading and cytoskeletal responses to the extracellular matrix component thrombospondin-1; the human gene was cloned and localized to chromosome 7q32.\",\n      \"method\": \"cDNA cloning, physical mapping, FISH\",\n      \"journal\": \"Cytogenetics and cell genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — cDNA cloning and localization; functional role in cell spreading/cytoskeletal response attributed from earlier mouse studies referenced in the abstract, not newly demonstrated here\",\n      \"pmids\": [\"10640805\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"A splice-region variant in MKLN1 (c.400+3A>C) causes exon 4 skipping and a reading-frame shift, leading to lethal acrodermatitis (LAD) in Bull Terriers, demonstrating that loss of functional MKLN1 protein causes a disease phenotype involving poor growth, immune deficiency, and skin lesions.\",\n      \"method\": \"Genome-wide association study, haplotype analysis, whole-genome sequencing, RT-PCR of skin RNA from affected vs. control dogs\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — GWAS mapping + perfect case-control association (46 cases, 294 controls) + RT-PCR confirmation of aberrant splicing; multiple orthogonal methods in one study\",\n      \"pmids\": [\"29565995\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MKLN1 protein (together with ZMYND19) accumulates upon CTLH E3 ligase (MAEA subunit) knockout, associates with lysosome outer membranes, binds Raptor and RagA/C, and blocks a late step of mTORC1 activation by disrupting mTORC1 interaction with Rheb and with mTORC1 substrates S6K and 4E-BP1, independently of the tuberous sclerosis complex; CTLH-mediated ubiquitin/proteasome degradation of MKLN1 thus tunes mTORC1 activity.\",\n      \"method\": \"Genome-wide CRISPR/Cas9 screen, MAEA knockout, co-immunoprecipitation (MKLN1/ZMYND19/Raptor/RagA/C), lysosomal fractionation, mTORC1 activity assays, proteasome inhibitor treatment\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, subcellular fractionation, CRISPR KO with defined pathway phenotype, multiple orthogonal methods; peer-reviewed replication of preprint findings\",\n      \"pmids\": [\"41315365\", \"38746323\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MKLN1 is required for assembly of CTLH-MKLN1 E3 ubiquitin ligase complexes (distinct from CTLH-WDR26 assemblies); Mkln1-/- mice show reduced somatic hypermutation and class switch recombination due to increased UNG2 levels, and display increased germinal center B cells and B-cell developmental defects, indicating that CTLH-MKLN1 complexes regulate substrates beyond FAM72A.\",\n      \"method\": \"Mkln1-/- mouse genetic knockout, flow cytometry of B-cell populations, somatic hypermutation frequency assay, class switch recombination assay, UNG2 protein level measurement\",\n      \"journal\": \"Journal of immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic KO with multiple specific cellular phenotype readouts (SHM, CSR, B-cell development) and protein-level mechanistic link to UNG2 accumulation\",\n      \"pmids\": [\"40838616\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MKLN1 encodes muskelin, an intracellular protein that (1) mediates cell spreading and cytoskeletal responses to thrombospondin-1, (2) assembles into CTLH-MKLN1 E3 ubiquitin ligase complexes that target UNG2 degradation to support B-cell antibody diversification, and (3) acts—when not degraded by the CTLH complex—as a negative regulator of mTORC1 at the lysosomal membrane by associating with ZMYND19, binding Raptor and RagA/C, and blocking mTORC1 interaction with Rheb and its substrates; loss-of-function of MKLN1 in dogs causes a lethal genodermatosis (LAD) via exon-skipping and frameshift mutation.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"MKLN1 encodes muskelin, an intracellular adaptor protein that integrates cytoskeletal, ubiquitin-ligase, and growth-signaling functions [#0, #2]. Originally identified as a mediator of cell spreading and cytoskeletal responses to the extracellular matrix component thrombospondin-1 [#0], muskelin is now established as a substrate and assembly factor of the CTLH E3 ubiquitin ligase: MKLN1 is required for the formation of CTLH-MKLN1 complexes (distinct from CTLH-WDR26 assemblies), and these complexes target UNG2 for degradation to support antibody diversification, since Mkln1-deficient mice show reduced somatic hypermutation and class switch recombination from UNG2 accumulation alongside altered germinal-center and developmental B-cell populations [#3]. When not degraded by the CTLH complex, MKLN1 accumulates at the lysosomal outer membrane together with ZMYND19, binds Raptor and RagA/C, and blocks a late step of mTORC1 activation by disrupting mTORC1 interaction with Rheb and with its substrates S6K and 4E-BP1, independently of the tuberous sclerosis complex—so CTLH-mediated degradation of MKLN1 tunes mTORC1 activity [#2]. Loss-of-function of MKLN1 via a splice variant causing exon skipping and frameshift produces lethal acrodermatitis, a genodermatosis with poor growth, immune deficiency, and skin lesions [#1].\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Established the first functional identity of human muskelin by cloning the gene and linking it to cytoskeletal responses to the extracellular matrix.\",\n      \"evidence\": \"cDNA cloning, physical mapping, and FISH localization to chromosome 7q32\",\n      \"pmids\": [\"10640805\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Cell-spreading/cytoskeletal function attributed from prior mouse work, not newly demonstrated here\",\n        \"No molecular partners or biochemical mechanism defined\",\n        \"No connection to ubiquitin ligase or mTORC1 functions\"\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Demonstrated that loss of functional MKLN1 causes disease, defining an in vivo requirement for the protein in growth, immunity, and skin integrity.\",\n      \"evidence\": \"GWAS, haplotype analysis, whole-genome sequencing, and RT-PCR confirmation of exon-4 skipping in affected vs. control dogs (lethal acrodermatitis)\",\n      \"pmids\": [\"29565995\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Molecular mechanism connecting MKLN1 loss to the skin/immune phenotype not resolved\",\n        \"Did not identify MKLN1 protein partners or pathway\",\n        \"Phenotype defined in dogs; human disease relevance not addressed\"\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined a signaling mechanism: MKLN1 is a CTLH ligase substrate that, when stabilized, acts as a lysosomal negative regulator of mTORC1.\",\n      \"evidence\": \"Genome-wide CRISPR screen, MAEA knockout, reciprocal Co-IP (MKLN1/ZMYND19/Raptor/RagA/C), lysosomal fractionation, mTORC1 activity assays, and proteasome inhibition\",\n      \"pmids\": [\"41315365\", \"38746323\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis for how MKLN1/ZMYND19 occlude Rheb and substrate access not resolved\",\n        \"Physiological conditions that trigger MKLN1 stabilization vs. degradation not defined\",\n        \"Role of the ancestral thrombospondin/cytoskeletal function in this pathway unaddressed\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Established MKLN1 as an obligate assembly factor for a distinct CTLH-MKLN1 ligase that controls antibody diversification through UNG2 turnover.\",\n      \"evidence\": \"Mkln1-/- mice with flow cytometry of B-cell populations, somatic hypermutation and class switch recombination assays, and UNG2 protein-level measurement\",\n      \"pmids\": [\"40838616\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Full substrate repertoire of CTLH-MKLN1 beyond UNG2 and FAM72A not enumerated\",\n        \"Molecular determinants distinguishing CTLH-MKLN1 from CTLH-WDR26 assemblies not defined\",\n        \"Link between this ligase function and the mTORC1-regulatory pool of MKLN1 not integrated\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How MKLN1's distinct roles—cytoskeletal/thrombospondin response, CTLH-MKLN1 ligase assembly, and lysosomal mTORC1 regulation—are coordinated within a cell remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No structural model unifying its adaptor functions\",\n        \"Conditions partitioning MKLN1 between ligase assembly and degradation unknown\",\n        \"Mechanistic basis of the original cytoskeletal/thrombospondin role uncharacterized in the available corpus\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [2, 3]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005764\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"complexes\": [\n      \"CTLH-MKLN1 E3 ubiquitin ligase complex\"\n    ],\n    \"partners\": [\n      \"ZMYND19\",\n      \"RPTOR\",\n      \"RRAGA\",\n      \"RRAGC\",\n      \"MAEA\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":4,"faith_total":4,"faith_pct":100.0}}