期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1994
卷号:91
期号:24
页码:11728-11732
DOI:10.1073/pnas.91.24.11728
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Caveolae are small invaginations of the plasma membrane 50-100 nm in diameter. Since calcium channels, inositol 1,4,5-trisphosphate receptors, and heterotrimeric GTP-binding proteins (G proteins) are localized in caveolae, they may participate in signal transduction by G protein-coupled receptors. Here we show that the G protein-coupled endothelin receptor subtype A (ETA) and its bound endothelin ligand are found in plasma membrane caveolae. ETA and its bound ligand coimmunoprecipitate with caveolin, a structural component of caveolae, in extracts of cells expressing transfected ETA receptors. Confocal fluorescence microscopy shows colocalization of ETA receptors and caveolin in micropatches at or near the plasma membrane, in the absence of endothelin ligands. These observations demonstrate a functional role for plasma membrane caveolae in signal transduction by this G protein-coupled receptor.