细胞生物学
G蛋白
胞吐
分泌物
毒蕈碱乙酰胆碱受体
化学
蛋白激酶C
受体
生物
信号转导
生物化学
作者
Xiao Ke Chen,Lie Cheng Wang,Yang Zhou,Qian Cai,Murali Prakriya,Kai Lai Duan,Zu Hang Sheng,Christopher J. Lingle,Zhuan Zhou
摘要
Exocytosis proceeds by either full fusion or 'kiss-and-run' between vesicle and plasma membrane. Switching between these two modes permits the cell to regulate the kinetics and amount of secretion. Here we show that ATP receptor activation reduces secretion downstream from cytosolic Ca2+ elevation in rat adrenal chromaffin cells. This reduction is mediated by activation of a pertussis toxin - sensitive G(i/o) protein, leading to activation of G(beta gamma) subunits, which promote the `kiss-and-run' mode by reducing the total open time of the fusion pore during a vesicle fusion event. Furthermore, parallel activation of the muscarinic acetylcholine receptor removes the inhibitory effects of ATP on secretion. This is mediated by a G(q) pathway through protein kinase C activation. The inhibitory effects of ATP and its reversal by protein kinase C activation are also shared by opioids and somatostatin. Thus, a variety of G protein pathways exist to modulate Ca2+-evoked secretion at specific steps in fusion pore formation.
科研通智能强力驱动
Strongly Powered by AbleSci AI