{"gene":"MKS1","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":2006,"finding":"MKS1 protein localizes to basal bodies in ciliated epithelial cells; siRNA-mediated knockdown of Mks1 blocks centriole migration to the apical membrane and consequent primary cilium formation. Co-immunoprecipitation shows MKS1 physically interacts with meckelin (MKS3 gene product).","method":"siRNA knockdown, co-immunoprecipitation, immunofluorescence localization","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus functional knockdown with specific ciliary phenotype, two orthogonal methods in one study","pmids":["17185389"],"is_preprint":false},{"year":2006,"finding":"MKS1 was identified as a component of the flagellar apparatus basal body proteome by comparative genomics and proteomics, implicating it in ciliary functions.","method":"Comparative genomics/proteomics, in situ hybridization in mouse embryos","journal":"Nature genetics","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — proteomics identification plus expression pattern, no direct functional assay for MKS1 mechanism in this paper","pmids":["16415886"],"is_preprint":false},{"year":2009,"finding":"In vivo loss of mouse Mks1 leads to defective cilia formation in most tissues (but does not interfere with apical localization of epithelial basal bodies), and causes altered Hedgehog pathway signaling (expansion of Shh signaling domain in neural tube and limb).","method":"Mouse knockout, neural tube/limb patterning analysis, in vivo ciliogenesis assessment","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean in vivo loss-of-function with defined cellular and signaling phenotypes, replicated across multiple tissues","pmids":["19776033"],"is_preprint":false},{"year":2009,"finding":"Stable shRNA knockdown of Mks1 in IMCD3 cells induced multi-ciliated and multi-centrosomal phenotypes, demonstrating that MKS1 is required for regulating cilia length and number through modulation of centrosome duplication.","method":"Stable shRNA knockdown, immunofluorescence for cilia and centrosomes","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean KD with defined cellular phenotype, single lab","pmids":["19515853"],"is_preprint":false},{"year":2009,"finding":"C. elegans MKS-1 and its related proteins MKSR-1 and MKSR-2 (B9-domain proteins) all localize to transition zones/basal bodies of sensory cilia in a largely co-dependent manner, indicating functional interdependence. Disrupting human MKSR1 or MKSR2 causes ciliogenesis defects. Genetic interactions between double mks/mksr C. elegans mutants manifest as increased lifespan due to abnormal insulin-IGF-I signaling.","method":"Fluorescence localization in C. elegans, RNAi/genetic knockouts, epistasis analysis, lifespan assay","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (localization, genetics, pathway epistasis) across C. elegans and human cells","pmids":["19208769"],"is_preprint":false},{"year":2010,"finding":"Mks1 localizes to the mother centriole from which the cilium is generated in wild-type cells. A deletion mutation (del64-323) spanning the B9 domain prevents Mks1 from localizing to the centriole without disrupting centriole assembly itself, causing ciliogenesis failure in motile and non-motile cilia and disrupted Shh signaling (failed floor plate specification, expanded anterior Shh domain, reduced Gli3 repressor function).","method":"Mouse mutant analysis, immunofluorescence localization, Shh pathway readout (Gli2/Gli3 expression), fluorescent bead node flow assay","journal":"Disease models & mechanisms","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo mouse model with localization, domain mutagenesis (deletion), and multiple signaling pathway readouts","pmids":["21045211"],"is_preprint":false},{"year":2010,"finding":"Genetic epistasis in C. elegans shows mks-1 and mks-3 function in a pathway together, and this pathway interacts with a separate nphp-1/nphp-4 pathway to influence cilia positioning, orientation, and formation; combined disruption of both pathways has cell non-autonomous effects on sensilla.","method":"C. elegans genetic epistasis, double mutant analysis, cilia phenotype scoring","journal":"Journal of the American Society of Nephrology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with multiple pathway combinations, single lab","pmids":["20150540"],"is_preprint":false},{"year":2011,"finding":"MKS1-related B9-domain protein B9d2 binds IFT particle components and contributes to ciliary localization of Inversin (Nephrocystin 2), supporting transport of Opsin but not Peripherin to photoreceptor cilia.","method":"Co-immunoprecipitation, zebrafish in vivo knockdown, ciliary cargo trafficking assay","journal":"The EMBO journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus in vivo functional validation; finding is for MKS1-related protein B9d2, not MKS1 itself directly","pmids":["21602787"],"is_preprint":false},{"year":2015,"finding":"MKS1 functions at the transition zone to regulate ciliary INPP5E content through an ARL13B-dependent mechanism; patient fibroblasts with MKS1 mutations show decreased ciliary ARL13B and INPP5E levels, and this is recapitulated in 3D spheroid rescue assays with mutant MKS1 alleles.","method":"Immunofluorescence in patient fibroblasts, 3D spheroid rescue assay, quantification of ciliary protein levels","journal":"Journal of medical genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional rescue assay plus patient cell phenotyping with two ciliary markers, single lab","pmids":["26490104"],"is_preprint":false},{"year":2017,"finding":"Genetic double-mutant analysis shows Mks1 cooperates with BBS4 (BBSome) to mediate trafficking of ARL13B (a ciliary membrane protein) to the cilium; Mks1;Bbs4 double mutants have exacerbated Hedgehog patterning defects and disrupted ciliary structure. Mks1 also genetically interacts with IFT-B component Ift172 and retrograde motor Dync2h1, demonstrating that the MKS transition zone complex facilitates IFT for cilium assembly.","method":"Mouse double-mutant epistasis, immunofluorescence for ARL13B ciliary localization, Hedgehog pathway readouts","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple double-mutant combinations with defined trafficking and signaling phenotypes, in vivo mouse model","pmids":["28291807"],"is_preprint":false},{"year":2020,"finding":"MKS1, B9D2, and B9D1 form a complex in the order MKS1-B9D2-B9D1; their localization to the transition zone is interdependent. This B9-domain complex acts as a diffusion barrier for ciliary membrane proteins. MKS1-KO and B9D2-KO cells show that the complex is involved in, but not essential for, normal cilia biogenesis, whereas complex formation is crucial for the diffusion barrier function.","method":"Co-immunoprecipitation, CRISPR knockout cells, rescue experiments, fluorescence recovery after photobleaching (diffusion barrier assay)","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — reconstitution of complex by Co-IP, KO cell lines with rescue, and functional diffusion barrier assay with multiple orthogonal methods","pmids":["32726168"],"is_preprint":false},{"year":2020,"finding":"The c.1058delG mutation disrupts the B9 domain of MKS1, attenuates MKS1 interaction with B9D2, and impairs ciliary localization at the transition zone, demonstrating that the B9 domain is essential for integrity of the B9 protein complex and TZ localization.","method":"Functional studies in patient-derived cells, co-immunoprecipitation, immunofluorescence localization","journal":"Frontiers in genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — Co-IP and localization in patient cells, single lab, single paper","pmids":["33193692"],"is_preprint":false},{"year":2022,"finding":"MKS1 physically interacts with UBE2E1 (an E2 ubiquitin-conjugating enzyme) and RNF34 (an E3 ligase); UBE2E1 mediates both regulatory and degradative ubiquitination of MKS1, and UBE2E1 levels are co-dependent with MKS1. Loss of Mks1 sensitizes cells to proteasomal disruption, causing abnormal accumulation of ubiquitinated proteins. UBE2E1 polyubiquitinates β-catenin, and processing of phosphorylated β-catenin occurs at the ciliary base through MKS1-UBE2E1 functional interaction, regulating canonical Wnt signaling.","method":"Co-immunoprecipitation, mouse model (Mks1 loss), immunofluorescence colocalization, Wnt/β-catenin reporter assays, ubiquitination assays","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (Co-IP, KO mouse model, ubiquitination assays, Wnt reporter), mechanistic pathway placement, single rigorous study","pmids":["35170427"],"is_preprint":false},{"year":2022,"finding":"Two novel MKS1 mutations (c.350C>A nonsense and c.1408-14A>G splice) disrupt the B9-C2 domain and attenuate MKS1 interaction with B9D2, the essential component of the ciliary transition zone.","method":"RT-PCR for aberrant splicing, Co-immunoprecipitation for B9D2 interaction","journal":"Frontiers in genetics","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single Co-IP for interaction disruption, single lab, limited mechanistic follow-up","pmids":["35360848"],"is_preprint":false},{"year":2002,"finding":"In yeast Saccharomyces cerevisiae, Mks1p is a negative regulator of the RTG mitochondria-to-nucleus signaling pathway, acting between Rtg2p and the bHLH transcription factors Rtg1p/Rtg3p; Mks1p is a phosphoprotein that forms a complex with Rtg2p. In mks1Δ cells, RTG target gene expression is constitutive and bypasses Rtg2p requirement.","method":"Genetic epistasis (mks1Δ, rtgΔ mutants), phosphorylation analysis, co-complex detection","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis plus biochemical complex detection in yeast; note this is the yeast Mks1p, a different protein from human MKS1","pmids":["11907262"],"is_preprint":false},{"year":2000,"finding":"In yeast, Mks1p is required for de novo generation of the [URE3] prion; mks1Δ strains cannot generate [URE3] de novo but can propagate introduced [URE3]. Mks1p negatively regulates Ure2p and is itself negatively regulated by ammonia and the Ras-cAMP pathway.","method":"Yeast genetics (mks1Δ), prion induction/propagation assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic loss-of-function with specific prion generation phenotype; yeast Mks1p distinct from human MKS1","pmids":["10823922"],"is_preprint":false},{"year":1993,"finding":"In S. cerevisiae, MKS1 encodes a negative regulator acting downstream of the Ras-cAMP pathway: overexpression inhibits growth of cyr1 disruptants, and mks1 disruption partially suppresses the cyr1-230 temperature-sensitive mutation. MKS1 is involved in transcriptional regulation of several genes by cAMP.","method":"Yeast genetic overexpression and disruption, growth phenotype assays, suppressor analysis","journal":"Molecular & general genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis plus overexpression/disruption with defined pathway placement; yeast MKS1 distinct from human MKS1","pmids":["8386801"],"is_preprint":false}],"current_model":"Human MKS1 is a B9-domain-containing protein that localizes to the transition zone (TZ) at the base of primary cilia, where it forms a complex with B9D2 and B9D1 (in the order MKS1-B9D2-B9D1) to act as a diffusion barrier for ciliary membrane proteins; MKS1 is required for normal ciliogenesis, regulates ciliary levels of INPP5E and ARL13B, cooperates with the BBSome and IFT machinery to traffic ciliary membrane proteins (including ARL13B) and mediate Hedgehog signaling, and interacts with the E2 ubiquitin-conjugating enzyme UBE2E1 at the ciliary base to process phosphorylated β-catenin and regulate canonical Wnt signaling."},"narrative":{"mechanistic_narrative":"Human MKS1 is a B9-domain protein that operates at the ciliary transition zone to govern ciliogenesis, ciliary membrane composition, and ciliary signaling [PMID:19776033, PMID:32726168]. It localizes to basal bodies and the mother centriole from which the cilium grows, and its loss disrupts cilium formation across most tissues; the B9 domain is required for MKS1's own centriolar/transition-zone localization, and its deletion causes ciliogenesis failure [PMID:17185389, PMID:21045211]. At the transition zone MKS1 assembles with B9D2 and B9D1 into an ordered MKS1-B9D2-B9D1 complex whose members localize interdependently and which functions as a diffusion barrier for ciliary membrane proteins [PMID:32726168]. Through this position MKS1 regulates ciliary levels of ARL13B and INPP5E and cooperates with the BBSome (BBS4) and IFT machinery (IFT172, DYNC2H1) to traffic ARL13B and execute Hedgehog patterning, with loss of Mks1 expanding Shh signaling domains and impairing Gli3 repressor function [PMID:21045211, PMID:26490104, PMID:28291807]. MKS1 additionally interacts with the E2 ubiquitin-conjugating enzyme UBE2E1 and the E3 ligase RNF34: UBE2E1 ubiquitinates MKS1 reciprocally and, through a MKS1-UBE2E1 interaction at the ciliary base, processes phosphorylated β-catenin to regulate canonical Wnt signaling [PMID:35170427]. Pathogenic MKS1 mutations that disrupt the B9 domain attenuate the MKS1-B9D2 interaction and abolish transition-zone localization, linking MKS1 to ciliopathy [PMID:33193692].","teleology":[{"year":2006,"claim":"Established MKS1 as a ciliary protein by placing it at the basal body and showing it is required for centriole migration and cilium formation, while identifying a physical partner.","evidence":"siRNA knockdown, reciprocal co-immunoprecipitation, and immunofluorescence in ciliated epithelial cells; parallel basal-body proteomics","pmids":["17185389","16415886"],"confidence":"High","gaps":["Molecular function within the cilium not defined","Mechanism of meckelin interaction not resolved"]},{"year":2009,"claim":"In vivo loss-of-function defined MKS1 as required for ciliogenesis and for restraining Hedgehog signaling, connecting it to developmental patterning.","evidence":"Mouse knockout with neural tube and limb patterning analysis; stable shRNA in IMCD3 cells; C. elegans B9-protein localization and genetics","pmids":["19776033","19515853","19208769"],"confidence":"High","gaps":["How MKS1 limits the Shh domain mechanistically unclear","Centrosome-duplication role from cell-line KD not validated in vivo"]},{"year":2010,"claim":"Domain mapping showed the B9 domain is required for MKS1 localization to the centriole, separating its targeting from centriole assembly itself.","evidence":"Mouse del64-323 mutant analysis with localization, Shh readouts, and node flow assay; C. elegans epistasis with mks-3 and nphp pathways","pmids":["21045211","20150540"],"confidence":"High","gaps":["Structural basis of B9-domain targeting unknown","Relationship between transition-zone and centriolar pools not resolved"]},{"year":2015,"claim":"Linked MKS1 transition-zone function to control of specific ciliary membrane proteins, defining an ARL13B-dependent route for INPP5E enrichment.","evidence":"Patient fibroblast immunofluorescence and 3D spheroid rescue with mutant MKS1 alleles","pmids":["26490104"],"confidence":"Medium","gaps":["Direct biochemical link between MKS1 and ARL13B/INPP5E not shown","Single lab"]},{"year":2017,"claim":"Genetic epistasis placed the MKS transition-zone complex upstream of, and cooperating with, the BBSome and IFT machinery in trafficking ARL13B for Hedgehog signaling.","evidence":"Mouse Mks1;Bbs4, Mks1;Ift172, Mks1;Dync2h1 double-mutant analysis with ARL13B localization and Hedgehog readouts","pmids":["28291807"],"confidence":"High","gaps":["Whether interactions with BBSome/IFT are physical or purely genetic not established","Direct cargo-recognition mechanism unknown"]},{"year":2020,"claim":"Reconstituted the ordered MKS1-B9D2-B9D1 complex and showed its essential role is the ciliary diffusion barrier rather than cilium biogenesis per se.","evidence":"Co-IP, CRISPR KO cells with rescue, and FRAP-based diffusion-barrier assay; patient c.1058delG mutation disrupting B9 domain and B9D2 binding","pmids":["32726168","33193692"],"confidence":"High","gaps":["Structure of the assembled complex not determined","How the barrier discriminates among membrane proteins unknown"]},{"year":2022,"claim":"Identified a ubiquitin-pathway role for MKS1, coupling it to UBE2E1/RNF34 and to processing of phosphorylated β-catenin at the ciliary base to regulate canonical Wnt signaling.","evidence":"Co-IP, Mks1-loss mouse model, ubiquitination assays, and Wnt/β-catenin reporter assays; additional patient mutations attenuating B9D2 binding","pmids":["35170427","35360848"],"confidence":"High","gaps":["Direct enzymatic relationship between MKS1 and β-catenin ubiquitination not fully resolved","How ciliary localization gates Wnt processing unclear"]},{"year":null,"claim":"How MKS1's transition-zone barrier function, IFT/BBSome cooperation, and UBE2E1-Wnt activities are mechanistically integrated, and the structural basis of cargo selectivity, remain open.","evidence":"","pmids":[],"confidence":"High","gaps":["No high-resolution structure of the MKS1-B9D2-B9D1 complex","Direct substrate/cargo recognition mechanism undefined","Integration of ciliary and ubiquitin/Wnt functions unresolved"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[10]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[12]}],"localization":[{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[0,5]},{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[2,10]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[2,9,12]},{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[0,10]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[2,5]}],"complexes":["MKS1-B9D2-B9D1 transition zone complex"],"partners":["B9D2","B9D1","MKS3","UBE2E1","RNF34"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9NXB0","full_name":"Tectonic-like complex member MKS1","aliases":["Meckel syndrome type 1 protein"],"length_aa":559,"mass_kda":64.5,"function":"Component of the tectonic-like complex, a complex localized at the transition zone of primary cilia and acting as a barrier that prevents diffusion of transmembrane proteins between the cilia and plasma membranes. Involved in centrosome migration to the apical cell surface during early ciliogenesis. Required for ciliary structure and function, including a role in regulating length and appropriate number through modulating centrosome duplication. Required for cell branching morphology","subcellular_location":"Cytoplasm, cytoskeleton, cilium basal body; Cytoplasm, cytoskeleton, microtubule organizing center, centrosome","url":"https://www.uniprot.org/uniprotkb/Q9NXB0/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MKS1","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/MKS1","total_profiled":1310},"omim":[{"mim_id":"619879","title":"MECKEL SYNDROME 14; MKS14","url":"https://www.omim.org/entry/619879"},{"mim_id":"619185","title":"JOUBERT SYNDROME 37; JBTS37","url":"https://www.omim.org/entry/619185"},{"mim_id":"617728","title":"CENTROSOMAL PROTEIN, 295-KD; CEP295","url":"https://www.omim.org/entry/617728"},{"mim_id":"617562","title":"MECKEL SYNDROME 13; MKS13","url":"https://www.omim.org/entry/617562"},{"mim_id":"617121","title":"JOUBERT SYNDROME 28; JBTS28","url":"https://www.omim.org/entry/617121"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"},{"location":"Nucleoli","reliability":"Approved"},{"location":"Basal body","reliability":"Approved"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/MKS1"},"hgnc":{"alias_symbol":["FLJ20345","POC12","BBS13"],"prev_symbol":["MKS"]},"alphafold":{"accession":"Q9NXB0","domains":[{"cath_id":"-","chopping":"8-41_71-85_122-138_183-272","consensus_level":"medium","plddt":77.7767,"start":8,"end":272},{"cath_id":"2.60.40.150","chopping":"311-385_393-468_476-499","consensus_level":"high","plddt":87.0278,"start":311,"end":499}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NXB0","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NXB0-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NXB0-F1-predicted_aligned_error_v6.png","plddt_mean":73.56},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MKS1","jax_strain_url":"https://www.jax.org/strain/search?query=MKS1"},"sequence":{"accession":"Q9NXB0","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9NXB0.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9NXB0/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NXB0"}},"corpus_meta":[{"pmid":"15990873","id":"PMC_15990873","title":"The MAP kinase substrate MKS1 is a regulator of plant defense responses.","date":"2005","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/15990873","citation_count":372,"is_preprint":false},{"pmid":"16421520","id":"PMC_16421520","title":"MAPKAP kinases - MKs - two's company, three's a crowd.","date":"2006","source":"Nature reviews. Molecular cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16421520","citation_count":325,"is_preprint":false},{"pmid":"17185389","id":"PMC_17185389","title":"The Meckel-Gruber Syndrome proteins MKS1 and meckelin interact and are required for primary cilium formation.","date":"2006","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/17185389","citation_count":209,"is_preprint":false},{"pmid":"16415886","id":"PMC_16415886","title":"MKS1, encoding a component of the flagellar apparatus basal body proteome, is mutated in Meckel syndrome.","date":"2006","source":"Nature genetics","url":"https://pubmed.ncbi.nlm.nih.gov/16415886","citation_count":184,"is_preprint":false},{"pmid":"19776033","id":"PMC_19776033","title":"A mouse model for Meckel syndrome reveals Mks1 is required for ciliogenesis and Hedgehog signaling.","date":"2009","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/19776033","citation_count":113,"is_preprint":false},{"pmid":"19515853","id":"PMC_19515853","title":"Ciliary and centrosomal defects associated with mutation and depletion of the Meckel syndrome genes MKS1 and MKS3.","date":"2009","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/19515853","citation_count":100,"is_preprint":false},{"pmid":"11907262","id":"PMC_11907262","title":"RTG-dependent mitochondria-to-nucleus signaling is regulated by MKS1 and is linked to formation of yeast prion [URE3].","date":"2002","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/11907262","citation_count":86,"is_preprint":false},{"pmid":"21602787","id":"PMC_21602787","title":"Nephrocystins and MKS proteins interact with IFT particle and facilitate transport of selected ciliary cargos.","date":"2011","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/21602787","citation_count":81,"is_preprint":false},{"pmid":"26779481","id":"PMC_26779481","title":"MAPK-Activated Protein Kinases (MKs): Novel Insights and Challenges.","date":"2016","source":"Frontiers in cell and developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/26779481","citation_count":73,"is_preprint":false},{"pmid":"21045211","id":"PMC_21045211","title":"Disruption of Mks1 localization to the mother centriole causes cilia defects and developmental malformations in Meckel-Gruber syndrome.","date":"2010","source":"Disease models & mechanisms","url":"https://pubmed.ncbi.nlm.nih.gov/21045211","citation_count":73,"is_preprint":false},{"pmid":"17397051","id":"PMC_17397051","title":"Spectrum of MKS1 and MKS3 mutations in Meckel syndrome: a genotype-phenotype correlation. Mutation in brief #960. Online.","date":"2007","source":"Human mutation","url":"https://pubmed.ncbi.nlm.nih.gov/17397051","citation_count":72,"is_preprint":false},{"pmid":"21493627","id":"PMC_21493627","title":"B9D1 is revealed as a novel Meckel syndrome (MKS) gene by targeted exon-enriched next-generation sequencing and deletion analysis.","date":"2011","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/21493627","citation_count":67,"is_preprint":false},{"pmid":"19208769","id":"PMC_19208769","title":"Functional interactions between the ciliopathy-associated Meckel syndrome 1 (MKS1) protein and two novel MKS1-related (MKSR) proteins.","date":"2009","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/19208769","citation_count":66,"is_preprint":false},{"pmid":"17377820","id":"PMC_17377820","title":"Molecular diagnostics of Meckel-Gruber syndrome highlights phenotypic differences between MKS1 and MKS3.","date":"2007","source":"Human 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genetics","url":"https://pubmed.ncbi.nlm.nih.gov/17935508","citation_count":17,"is_preprint":false},{"pmid":"27377014","id":"PMC_27377014","title":"MKS1 mutations cause Joubert syndrome with agenesis of the corpus callosum.","date":"2016","source":"European journal of medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/27377014","citation_count":14,"is_preprint":false},{"pmid":"35170427","id":"PMC_35170427","title":"Regulation of canonical Wnt signalling by the ciliopathy protein MKS1 and the E2 ubiquitin-conjugating enzyme UBE2E1.","date":"2022","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/35170427","citation_count":12,"is_preprint":false},{"pmid":"2542592","id":"PMC_2542592","title":"Analysis of a large-T-antigen variant expressed in simian virus 40-transformed mouse cell line mKS-A.","date":"1989","source":"Journal of virology","url":"https://pubmed.ncbi.nlm.nih.gov/2542592","citation_count":8,"is_preprint":false},{"pmid":"1793072","id":"PMC_1793072","title":"SDZ MKS 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Part A","url":"https://pubmed.ncbi.nlm.nih.gov/27570071","citation_count":7,"is_preprint":false},{"pmid":"33193692","id":"PMC_33193692","title":"Novel Compound Heterozygous Variants in MKS1 Leading to Joubert Syndrome.","date":"2020","source":"Frontiers in genetics","url":"https://pubmed.ncbi.nlm.nih.gov/33193692","citation_count":6,"is_preprint":false},{"pmid":"34359301","id":"PMC_34359301","title":"Mild Clinical Presentation of Joubert Syndrome in a Male Adult Carrying Biallelic MKS1 Truncating Variants.","date":"2021","source":"Diagnostics (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/34359301","citation_count":6,"is_preprint":false},{"pmid":"35360848","id":"PMC_35360848","title":"Case Report: Preimplantation Genetic Testing for Meckel Syndrome Induced by Novel Compound Heterozygous Mutations of MKS1.","date":"2022","source":"Frontiers in genetics","url":"https://pubmed.ncbi.nlm.nih.gov/35360848","citation_count":4,"is_preprint":false},{"pmid":"40558825","id":"PMC_40558825","title":"Adiponectin Assists Thrombopoietic Agents in ITP Treatment by Enhancing Myosin-9/Rab6A-Mediated Trafficking of c-Mpl in MKs.","date":"2025","source":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/40558825","citation_count":2,"is_preprint":false},{"pmid":"34424238","id":"PMC_34424238","title":"Immunophenotyping and Cell Sorting of Human MKs from Human Primary Sources or Differentiated In Vitro from Hematopoietic Progenitors.","date":"2021","source":"Journal of visualized experiments : JoVE","url":"https://pubmed.ncbi.nlm.nih.gov/34424238","citation_count":1,"is_preprint":false},{"pmid":"39337559","id":"PMC_39337559","title":"Deciphering Transcriptomic Variations in Hematopoietic Lineages: HSCs, EBs, and MKs.","date":"2024","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/39337559","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19619,"output_tokens":4096,"usd":0.060149,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11902,"output_tokens":2876,"usd":0.065705,"stage2_stop_reason":"end_turn"},"total_usd":0.125854,"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\": 2006,\n      \"finding\": \"MKS1 protein localizes to basal bodies in ciliated epithelial cells; siRNA-mediated knockdown of Mks1 blocks centriole migration to the apical membrane and consequent primary cilium formation. Co-immunoprecipitation shows MKS1 physically interacts with meckelin (MKS3 gene product).\",\n      \"method\": \"siRNA knockdown, co-immunoprecipitation, immunofluorescence localization\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus functional knockdown with specific ciliary phenotype, two orthogonal methods in one study\",\n      \"pmids\": [\"17185389\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"MKS1 was identified as a component of the flagellar apparatus basal body proteome by comparative genomics and proteomics, implicating it in ciliary functions.\",\n      \"method\": \"Comparative genomics/proteomics, in situ hybridization in mouse embryos\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — proteomics identification plus expression pattern, no direct functional assay for MKS1 mechanism in this paper\",\n      \"pmids\": [\"16415886\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"In vivo loss of mouse Mks1 leads to defective cilia formation in most tissues (but does not interfere with apical localization of epithelial basal bodies), and causes altered Hedgehog pathway signaling (expansion of Shh signaling domain in neural tube and limb).\",\n      \"method\": \"Mouse knockout, neural tube/limb patterning analysis, in vivo ciliogenesis assessment\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean in vivo loss-of-function with defined cellular and signaling phenotypes, replicated across multiple tissues\",\n      \"pmids\": [\"19776033\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Stable shRNA knockdown of Mks1 in IMCD3 cells induced multi-ciliated and multi-centrosomal phenotypes, demonstrating that MKS1 is required for regulating cilia length and number through modulation of centrosome duplication.\",\n      \"method\": \"Stable shRNA knockdown, immunofluorescence for cilia and centrosomes\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean KD with defined cellular phenotype, single lab\",\n      \"pmids\": [\"19515853\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"C. elegans MKS-1 and its related proteins MKSR-1 and MKSR-2 (B9-domain proteins) all localize to transition zones/basal bodies of sensory cilia in a largely co-dependent manner, indicating functional interdependence. Disrupting human MKSR1 or MKSR2 causes ciliogenesis defects. Genetic interactions between double mks/mksr C. elegans mutants manifest as increased lifespan due to abnormal insulin-IGF-I signaling.\",\n      \"method\": \"Fluorescence localization in C. elegans, RNAi/genetic knockouts, epistasis analysis, lifespan assay\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (localization, genetics, pathway epistasis) across C. elegans and human cells\",\n      \"pmids\": [\"19208769\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Mks1 localizes to the mother centriole from which the cilium is generated in wild-type cells. A deletion mutation (del64-323) spanning the B9 domain prevents Mks1 from localizing to the centriole without disrupting centriole assembly itself, causing ciliogenesis failure in motile and non-motile cilia and disrupted Shh signaling (failed floor plate specification, expanded anterior Shh domain, reduced Gli3 repressor function).\",\n      \"method\": \"Mouse mutant analysis, immunofluorescence localization, Shh pathway readout (Gli2/Gli3 expression), fluorescent bead node flow assay\",\n      \"journal\": \"Disease models & mechanisms\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo mouse model with localization, domain mutagenesis (deletion), and multiple signaling pathway readouts\",\n      \"pmids\": [\"21045211\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Genetic epistasis in C. elegans shows mks-1 and mks-3 function in a pathway together, and this pathway interacts with a separate nphp-1/nphp-4 pathway to influence cilia positioning, orientation, and formation; combined disruption of both pathways has cell non-autonomous effects on sensilla.\",\n      \"method\": \"C. elegans genetic epistasis, double mutant analysis, cilia phenotype scoring\",\n      \"journal\": \"Journal of the American Society of Nephrology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with multiple pathway combinations, single lab\",\n      \"pmids\": [\"20150540\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"MKS1-related B9-domain protein B9d2 binds IFT particle components and contributes to ciliary localization of Inversin (Nephrocystin 2), supporting transport of Opsin but not Peripherin to photoreceptor cilia.\",\n      \"method\": \"Co-immunoprecipitation, zebrafish in vivo knockdown, ciliary cargo trafficking assay\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus in vivo functional validation; finding is for MKS1-related protein B9d2, not MKS1 itself directly\",\n      \"pmids\": [\"21602787\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"MKS1 functions at the transition zone to regulate ciliary INPP5E content through an ARL13B-dependent mechanism; patient fibroblasts with MKS1 mutations show decreased ciliary ARL13B and INPP5E levels, and this is recapitulated in 3D spheroid rescue assays with mutant MKS1 alleles.\",\n      \"method\": \"Immunofluorescence in patient fibroblasts, 3D spheroid rescue assay, quantification of ciliary protein levels\",\n      \"journal\": \"Journal of medical genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional rescue assay plus patient cell phenotyping with two ciliary markers, single lab\",\n      \"pmids\": [\"26490104\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Genetic double-mutant analysis shows Mks1 cooperates with BBS4 (BBSome) to mediate trafficking of ARL13B (a ciliary membrane protein) to the cilium; Mks1;Bbs4 double mutants have exacerbated Hedgehog patterning defects and disrupted ciliary structure. Mks1 also genetically interacts with IFT-B component Ift172 and retrograde motor Dync2h1, demonstrating that the MKS transition zone complex facilitates IFT for cilium assembly.\",\n      \"method\": \"Mouse double-mutant epistasis, immunofluorescence for ARL13B ciliary localization, Hedgehog pathway readouts\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple double-mutant combinations with defined trafficking and signaling phenotypes, in vivo mouse model\",\n      \"pmids\": [\"28291807\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"MKS1, B9D2, and B9D1 form a complex in the order MKS1-B9D2-B9D1; their localization to the transition zone is interdependent. This B9-domain complex acts as a diffusion barrier for ciliary membrane proteins. MKS1-KO and B9D2-KO cells show that the complex is involved in, but not essential for, normal cilia biogenesis, whereas complex formation is crucial for the diffusion barrier function.\",\n      \"method\": \"Co-immunoprecipitation, CRISPR knockout cells, rescue experiments, fluorescence recovery after photobleaching (diffusion barrier assay)\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — reconstitution of complex by Co-IP, KO cell lines with rescue, and functional diffusion barrier assay with multiple orthogonal methods\",\n      \"pmids\": [\"32726168\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"The c.1058delG mutation disrupts the B9 domain of MKS1, attenuates MKS1 interaction with B9D2, and impairs ciliary localization at the transition zone, demonstrating that the B9 domain is essential for integrity of the B9 protein complex and TZ localization.\",\n      \"method\": \"Functional studies in patient-derived cells, co-immunoprecipitation, immunofluorescence localization\",\n      \"journal\": \"Frontiers in genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — Co-IP and localization in patient cells, single lab, single paper\",\n      \"pmids\": [\"33193692\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"MKS1 physically interacts with UBE2E1 (an E2 ubiquitin-conjugating enzyme) and RNF34 (an E3 ligase); UBE2E1 mediates both regulatory and degradative ubiquitination of MKS1, and UBE2E1 levels are co-dependent with MKS1. Loss of Mks1 sensitizes cells to proteasomal disruption, causing abnormal accumulation of ubiquitinated proteins. UBE2E1 polyubiquitinates β-catenin, and processing of phosphorylated β-catenin occurs at the ciliary base through MKS1-UBE2E1 functional interaction, regulating canonical Wnt signaling.\",\n      \"method\": \"Co-immunoprecipitation, mouse model (Mks1 loss), immunofluorescence colocalization, Wnt/β-catenin reporter assays, ubiquitination assays\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (Co-IP, KO mouse model, ubiquitination assays, Wnt reporter), mechanistic pathway placement, single rigorous study\",\n      \"pmids\": [\"35170427\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Two novel MKS1 mutations (c.350C>A nonsense and c.1408-14A>G splice) disrupt the B9-C2 domain and attenuate MKS1 interaction with B9D2, the essential component of the ciliary transition zone.\",\n      \"method\": \"RT-PCR for aberrant splicing, Co-immunoprecipitation for B9D2 interaction\",\n      \"journal\": \"Frontiers in genetics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single Co-IP for interaction disruption, single lab, limited mechanistic follow-up\",\n      \"pmids\": [\"35360848\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"In yeast Saccharomyces cerevisiae, Mks1p is a negative regulator of the RTG mitochondria-to-nucleus signaling pathway, acting between Rtg2p and the bHLH transcription factors Rtg1p/Rtg3p; Mks1p is a phosphoprotein that forms a complex with Rtg2p. In mks1Δ cells, RTG target gene expression is constitutive and bypasses Rtg2p requirement.\",\n      \"method\": \"Genetic epistasis (mks1Δ, rtgΔ mutants), phosphorylation analysis, co-complex detection\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis plus biochemical complex detection in yeast; note this is the yeast Mks1p, a different protein from human MKS1\",\n      \"pmids\": [\"11907262\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"In yeast, Mks1p is required for de novo generation of the [URE3] prion; mks1Δ strains cannot generate [URE3] de novo but can propagate introduced [URE3]. Mks1p negatively regulates Ure2p and is itself negatively regulated by ammonia and the Ras-cAMP pathway.\",\n      \"method\": \"Yeast genetics (mks1Δ), prion induction/propagation assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic loss-of-function with specific prion generation phenotype; yeast Mks1p distinct from human MKS1\",\n      \"pmids\": [\"10823922\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"In S. cerevisiae, MKS1 encodes a negative regulator acting downstream of the Ras-cAMP pathway: overexpression inhibits growth of cyr1 disruptants, and mks1 disruption partially suppresses the cyr1-230 temperature-sensitive mutation. MKS1 is involved in transcriptional regulation of several genes by cAMP.\",\n      \"method\": \"Yeast genetic overexpression and disruption, growth phenotype assays, suppressor analysis\",\n      \"journal\": \"Molecular & general genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis plus overexpression/disruption with defined pathway placement; yeast MKS1 distinct from human MKS1\",\n      \"pmids\": [\"8386801\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"Human MKS1 is a B9-domain-containing protein that localizes to the transition zone (TZ) at the base of primary cilia, where it forms a complex with B9D2 and B9D1 (in the order MKS1-B9D2-B9D1) to act as a diffusion barrier for ciliary membrane proteins; MKS1 is required for normal ciliogenesis, regulates ciliary levels of INPP5E and ARL13B, cooperates with the BBSome and IFT machinery to traffic ciliary membrane proteins (including ARL13B) and mediate Hedgehog signaling, and interacts with the E2 ubiquitin-conjugating enzyme UBE2E1 at the ciliary base to process phosphorylated β-catenin and regulate canonical Wnt signaling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"Human MKS1 is a B9-domain protein that operates at the ciliary transition zone to govern ciliogenesis, ciliary membrane composition, and ciliary signaling [#2, #10]. It localizes to basal bodies and the mother centriole from which the cilium grows, and its loss disrupts cilium formation across most tissues; the B9 domain is required for MKS1's own centriolar/transition-zone localization, and its deletion causes ciliogenesis failure [#0, #5]. At the transition zone MKS1 assembles with B9D2 and B9D1 into an ordered MKS1-B9D2-B9D1 complex whose members localize interdependently and which functions as a diffusion barrier for ciliary membrane proteins [#10]. Through this position MKS1 regulates ciliary levels of ARL13B and INPP5E and cooperates with the BBSome (BBS4) and IFT machinery (IFT172, DYNC2H1) to traffic ARL13B and execute Hedgehog patterning, with loss of Mks1 expanding Shh signaling domains and impairing Gli3 repressor function [#5, #8, #9]. MKS1 additionally interacts with the E2 ubiquitin-conjugating enzyme UBE2E1 and the E3 ligase RNF34: UBE2E1 ubiquitinates MKS1 reciprocally and, through a MKS1-UBE2E1 interaction at the ciliary base, processes phosphorylated \\u03b2-catenin to regulate canonical Wnt signaling [#12]. Pathogenic MKS1 mutations that disrupt the B9 domain attenuate the MKS1-B9D2 interaction and abolish transition-zone localization, linking MKS1 to ciliopathy [#11].\",\n  \"teleology\": [\n    {\n      \"year\": 2006,\n      \"claim\": \"Established MKS1 as a ciliary protein by placing it at the basal body and showing it is required for centriole migration and cilium formation, while identifying a physical partner.\",\n      \"evidence\": \"siRNA knockdown, reciprocal co-immunoprecipitation, and immunofluorescence in ciliated epithelial cells; parallel basal-body proteomics\",\n      \"pmids\": [\"17185389\", \"16415886\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular function within the cilium not defined\", \"Mechanism of meckelin interaction not resolved\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"In vivo loss-of-function defined MKS1 as required for ciliogenesis and for restraining Hedgehog signaling, connecting it to developmental patterning.\",\n      \"evidence\": \"Mouse knockout with neural tube and limb patterning analysis; stable shRNA in IMCD3 cells; C. elegans B9-protein localization and genetics\",\n      \"pmids\": [\"19776033\", \"19515853\", \"19208769\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How MKS1 limits the Shh domain mechanistically unclear\", \"Centrosome-duplication role from cell-line KD not validated in vivo\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Domain mapping showed the B9 domain is required for MKS1 localization to the centriole, separating its targeting from centriole assembly itself.\",\n      \"evidence\": \"Mouse del64-323 mutant analysis with localization, Shh readouts, and node flow assay; C. elegans epistasis with mks-3 and nphp pathways\",\n      \"pmids\": [\"21045211\", \"20150540\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of B9-domain targeting unknown\", \"Relationship between transition-zone and centriolar pools not resolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Linked MKS1 transition-zone function to control of specific ciliary membrane proteins, defining an ARL13B-dependent route for INPP5E enrichment.\",\n      \"evidence\": \"Patient fibroblast immunofluorescence and 3D spheroid rescue with mutant MKS1 alleles\",\n      \"pmids\": [\"26490104\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct biochemical link between MKS1 and ARL13B/INPP5E not shown\", \"Single lab\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Genetic epistasis placed the MKS transition-zone complex upstream of, and cooperating with, the BBSome and IFT machinery in trafficking ARL13B for Hedgehog signaling.\",\n      \"evidence\": \"Mouse Mks1;Bbs4, Mks1;Ift172, Mks1;Dync2h1 double-mutant analysis with ARL13B localization and Hedgehog readouts\",\n      \"pmids\": [\"28291807\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether interactions with BBSome/IFT are physical or purely genetic not established\", \"Direct cargo-recognition mechanism unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Reconstituted the ordered MKS1-B9D2-B9D1 complex and showed its essential role is the ciliary diffusion barrier rather than cilium biogenesis per se.\",\n      \"evidence\": \"Co-IP, CRISPR KO cells with rescue, and FRAP-based diffusion-barrier assay; patient c.1058delG mutation disrupting B9 domain and B9D2 binding\",\n      \"pmids\": [\"32726168\", \"33193692\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structure of the assembled complex not determined\", \"How the barrier discriminates among membrane proteins unknown\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified a ubiquitin-pathway role for MKS1, coupling it to UBE2E1/RNF34 and to processing of phosphorylated \\u03b2-catenin at the ciliary base to regulate canonical Wnt signaling.\",\n      \"evidence\": \"Co-IP, Mks1-loss mouse model, ubiquitination assays, and Wnt/\\u03b2-catenin reporter assays; additional patient mutations attenuating B9D2 binding\",\n      \"pmids\": [\"35170427\", \"35360848\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct enzymatic relationship between MKS1 and \\u03b2-catenin ubiquitination not fully resolved\", \"How ciliary localization gates Wnt processing unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How MKS1's transition-zone barrier function, IFT/BBSome cooperation, and UBE2E1-Wnt activities are mechanistically integrated, and the structural basis of cargo selectivity, remain open.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No high-resolution structure of the MKS1-B9D2-B9D1 complex\", \"Direct substrate/cargo recognition mechanism undefined\", \"Integration of ciliary and ubiquitin/Wnt functions unresolved\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [10]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [12]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [0, 5]},\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [2, 10]},\n      {\"term_id\": \"GO:0005813\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [2, 9, 12]},\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [0, 10]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [2, 5]}\n    ],\n    \"complexes\": [\n      \"MKS1-B9D2-B9D1 transition zone complex\"\n    ],\n    \"partners\": [\n      \"B9D2\",\n      \"B9D1\",\n      \"MKS3\",\n      \"UBE2E1\",\n      \"RNF34\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}