부산대학교 도서관

We show that receptor induced G protein [beta][gamma] subunit translocation from the plasma membrane to the Golgi allows a receptor to initiate fragmentation and regulate secretion. A lung epithelial cell line, A549, was shown to contain an endogenous translocating G protein y subunit and exhibit receptor-induced Golgi fragmentation. Receptor-induced Golgi fragmentation was inhibited by a shRNA specific to the endogenous translocating [gamma] subunit. A kinase defective protein kinase D and a phospholipase C [beta] inhibitor blocked receptor-induced Golgi fragmentation, suggesting a role for this process in secretion. Consistent with [beta][gamma] translocation dependence, fragmentation induced by receptor activation was inhibited by a dominant negative nontranslocating [gamma]3. Insulin secretion was shown to be induced by muscarinic receptor activation in a pancreatic [beta] cell line, NIT-1. Induction of insulin secretion was also inhibited by the dominant negative [gamma]3 subunit consistent with the Golgi fragmentation induced by [beta][gamma] complex translocation playing a role in secretion. G protein-coupled receptors | live cell imaging | signaling | insulin doi/ 10.1073/pnas. 1003042107