{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["009:25"], "contactPoint": {"@type": "vcard:Contact", "fn": "NIH", "hasEmail": "mailto:info@nih.gov"}, "description": "Background\n          Structural requirements for the \u03b21 integrin functions in cell adhesion, spreading and signaling have been well documented mainly for fibroblasts. In this study, we examined the reason for the reduced surface expression of \u03b21 integrin in human breast cancer MCF-7 cells compared to normal human breast epithelial (HBE) cells, both of which adhered to collagen type IV.\n        \n        \n          Results\n          The \u03b21 integrin immunoprecipitates from either HBE or MCF-7 cells involved \u03b1-actinin while actin coprecipitated with \u03b21 integrin from HBE cells but not from MCF-7 cells. Immunoblotting using the anti-phosphotyrosine (PY) antibody indicated the phosphorylation of \u03b21 integrin at least at tyrosine in both cells. Dephosphorylation of \u03b21 integrin from HBE cells by protein tyrosine phosphatase (PTP), but not by protein serine/threonine phosphatase (PP), caused dissociation of actin from \u03b21 integrin, although dephosphorylation of it from MCF-7 cells by either PTP or PP caused association of the two proteins. In MCF-7 cells \u03b21 integrin coprecipitated doublet of proteins having the Ca2+/calmodulin-dependent protein kinase (CaMK) II activity that was susceptible to KN-62, a specific inhibitor of CaMKII.\n        \n        \n          Conclusion\n          The results suggest that \u03b21 integrin is tyrosine phosphorylated and links with actin via \u03b1-actinin in HBE cells but prevented from linking with actin in MCF-7 cells by phosphorylation at both tyrosine and serine/threonine of \u03b21 integrin which forms a complex with \u03b1-actinin and CaMKII. Thus the linkage formation of \u03b21 integrin with actin may be differentially regulated by its tyrosine and serine/threonine phosphorylation in normal HBE cells and breast cancer MCF-7 cells.", "distribution": [{"@type": "dcat:Distribution", "description": "Visit the original government dataset for complete information, documentation, and data access.", "downloadURL": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC59887/", "mediaType": "text/html", "title": "Official Government Data Source"}], "identifier": "https://healthdata.gov/api/views/s78u-vzef", "issued": "2025-07-14", "keyword": ["nih", "breast-cancer-cells", "integrin-phosphorylation", "actin-cytoskeleton", "cell-adhesion"], "landingPage": "https://healthdata.gov/d/s78u-vzef", "modified": "2025-09-06", "programCode": ["009:033"], "publisher": {"@type": "org:Organization", "name": "National Institutes of Health"}, "theme": ["NIH"], "title": "The linkage between \u03b21 integrin and the actin cytoskeleton is differentially regulated by tyrosine and serine/threonine phosphorylation of \u03b21 integrin in normal and cancerous human breast cells"}