Mechanism of the glucose-induced second phase insulin secretion in pancreatic beta-cells

2014 Fiscal Year Final Research Report

• Project/Area Number: 25860756
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Metabolomics
• Research Institution: Kyorin University
• Principal Investigator: KYOTA Aoyagi 杏林大学, 医学部, 助教 (50453527)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: インスリン分泌 / 膵β細胞 / 糖尿病

Outline of Final Research Achievements

This study aimed to elucidate the molecular mechanism underlying the glucose-induced second phase insulin secretion in pancreatic beta-cells. To this end, I studied the roles of VAMP7, a member of v-SNARE proteins localized in some types of vesicles, and a motor protein, MyosinVa, on the second phase insulin secretion. Using MysoinVa spontaneous mutant mice and rats in which the MyosinVa expression level is severely reduced, I found that MyosinVa was not involved in the regulation of the second phase insulin secretion. On the other hand, mice genetically eliminating VAMP7 specifically in pancreatic beta-cells (VAMP7 bKO) showed selective reduction of the second phase insulin secretion. Because VAMP7 was not localized in insulin granules, and the morphology and intracellular distribution of insulin granules in VAMP7 bKO beta-cells were not altered, I speculated that VAMP7 would regulate the second phase insulin secretion by an indirect mechanism.

Free Research Field

インスリン分泌