{"doi":"10.1101/2021.11.10.467974","title":"A myosin chaperone, UNC-45A, is a novel regulator of intestinal epithelial barrier integrity and repair","abstract":"Abstract The actomyosin cytoskeleton serves as a key regulator of the integrity and remodeling of epithelial barriers by controlling assembly and functions of intercellular junctions and cell-matrix adhesions. While biochemical mechanisms that regulate activity of non-muscle myosin II (NM-II) in epithelial cells have been extensively investigated, little is known about assembly of the contractile myosin structures at the epithelial adhesion sites. UNC-45A is a cytoskeletal chaperone that is essential for proper folding of NM II heavy chains and myofilament assembly. We found abundant expression of UNC-45A in human intestinal epithelial cell (IEC) lines and in the epithelial layer of the normal human colon. Interestingly, protein levels of UNC-45A were decreased in colonic epithelium of patients with ulcerative colitis. CRISPR/Cas9-mediated knock-out of UNC-45A in HT-29 and SK-CO15 IEC disrupted epithelial barrier integrity, impaired assembly of epithelial adherence and tight junctions and attenuated cell migration. Consistently, decreased UNC-45 expression increased permeability of the Drosophila gut in vivo . The mechanisms underlying barrier disruptive and anti-migratory effects of UNC-45A depletion involved disorganization of the actomyosin bundles at epithelial junctions and the migrating cell edge. Loss of UNC-45A also decreased contractile forces at epithelial junctions and matrix adhesions. Expression of deletion mutants revealed roles for the myosin binding domain of UNC-45A in controlling IEC junctions and motility. Our findings uncover a novel mechanism that regulates integrity and restitution of the intestinal epithelial barrier, which may be impaired during mucosal inflammation.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2021,"id":219663,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9584,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":561055,"name":"Alexander X. Cartagena‐Rivera","orcid":"0000-0001-6227-2499","position":1,"is_corresponding":false},{"id":818374,"name":"Afshin Khan","orcid":"0000-0002-9003-5009","position":2,"is_corresponding":false},{"id":818375,"name":"Bert I. Crawford","orcid":"0000-0003-2528-6343","position":3,"is_corresponding":false},{"id":301787,"name":"Vani Narayanan","orcid":"0000-0002-5358-8472","position":4,"is_corresponding":false},{"id":301791,"name":"Daniel E. Conway","orcid":"0000-0001-6624-177X","position":5,"is_corresponding":false},{"id":818376,"name":"Jaakko Lehtimäki","orcid":"0000-0002-0002-0242","position":6,"is_corresponding":false},{"id":460720,"name":"Pekka Lappalainen","orcid":"0000-0001-6227-0354","position":7,"is_corresponding":false},{"id":294494,"name":"Florian Rieder","orcid":"0000-0002-9087-1568","position":8,"is_corresponding":false},{"id":398001,"name":"Michelle S. Longworth","orcid":"0000-0002-1313-1777","position":9,"is_corresponding":false},{"id":337145,"name":"Andrei I. Ivanov","orcid":"0000-0003-4823-209X","position":10,"is_corresponding":false},{"id":444188,"name":"Susana Lechuga","orcid":"0000-0003-0614-1990","position":0,"is_corresponding":true}],"reference_count":72,"raw_metadata":null,"created_at":"2026-07-18T23:53:38.409982Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}