Adenovirus-mediated silencing of Synaptotagmin 9 inhibits Ca2+-dependent insulin secretion in islets

被引：45

作者：

Iezzi, M

Eliasson, L

Fukuda, M

Wollheim, CB ^{[1
]}

机构：

[1] Univ Geneva, Med Ctr, Dept Cell Physiol & Metab, CH-1211 Geneva, Switzerland

[2] Dept Expt Med Sci, Div Diabet Metab & Endocrinol, S-22184 Lund, Sweden

[3] RIKEN, Fukuda Initiat Res Unit, Wako, Saitama 3510198, Japan

来源：

FEBS LETTERS | 2005年 / 579卷 / 23期

关键词：

pancreatic islets; insulin exocytosis; electron; microscopy; RNA interference; beta-cell;

D O I：

10.1016/j.febslet.2005.08.047

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Synaptotagmins (Syts) are involved in Ca2+-dependent insulin release. However, which Syt isoform is functional in primary beta-cells remains unknown. We demonstrate by electron microscopy of pancreatic islets, the association of Syt 9 with insulin granules. Silencing of Syt 9 by RNA interference adenovirus in islet cells had no effect on the expression of Syt 5, Syt 7 and Syt 3 isoforms. The latter was localized at the plasma membrane of pancreatic polypeptide cells. Insulin release in response to glucose or tolbutamide was strongly inhibited in Syt 9 deficient islets, whereas exocytosis potentiated by raising cAMP levels, was unaltered. Thus, Syt 9 may act as Ca2+ sensor for beta-cell secretion. (c) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

引用

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页码：5241 / 5246

页数：6

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