Calmodulin activation of adenylate cyclase in pancreatic islets.
نویسندگان
چکیده
Pancreatic islets contain calmodulin. The protein binds to a particulate fraction derived from the islets and stimulates adenylate cyclase activity in this subcellular fraction, both phenomena being activated by ionized calcium. A calcium-dependent stimulation of adenylate cyclase by endogenous calmodulin may contribute to the accumulation of adenosine 3',5'-monophosphate evoked by insulin releasing agents in the islet cells.
منابع مشابه
Rapid Publications Stimulation of Adenylate Cyclase by Ca and Calmodulin in Rat Islets of Langerhans Explanation for the Glucose-induced Increase in Cyclic AMP Levels
The effect of Ca and calmodulin has been studied on adenylate cyclase activity in homogenates of rat islets of Langerhans. EGTA had a stimulatory effect on the enzyme in accord with the known inhibitory effect of Ca. In contrast, the addition of Ca together with calmodulin is stimulatory and demonstrates the existence of a Ca-dependent adenylate cyclase in islets of Langerhans. It is suggested ...
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عنوان ژورنال:
- Science
دوره 206 4415 شماره
صفحات -
تاریخ انتشار 1979