Open AccessComplexin I regulates glucose-induced secretion in pancreatic β-cells
Author(s) -
Amar Abderrahmani,
Guy Niederhäuser,
Valérie Plaisance,
Marc-Estienne Roehrich,
Vincent Lenain,
Thierry Coppola,
Romano Regazzi,
Gérard Waeber
Publication year - 2004
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.01041
Subject(s) - biology , exocytosis , microbiology and biotechnology , beta cell , pancreatic islets , insulin , secretion , gene silencing , neurotransmitter , medicine , endocrinology , gene , islet , biochemistry , central nervous system
The neuronal-specific protein complexin I (CPX I) plays an important role in controlling the Ca2+-dependent neurotransmitter release. Since insulin exocytosis and neurotransmitter release rely on similar molecular mechanisms and that pancreatic β-cells and neuronal cells share the expression of many restricted genes, we investigated the potential role of CPX I in insulin-secreting cells. We found that pancreatic islets and several insulin-secreting cell lines express high levels of CPX I. The β-cell expression of CPX I is mediated by the presence of a neuron restrictive silencer element located within the regulatory region of the gene. This element bound the transcriptional repressor REST, which is found in most cell types with the exception of mature neuronal cells and β-cells. Overexpression of CPX I or silencing of the CPX I gene (Cplx1) by RNA interference led to strong impairment in β-cell secretion in response to nutrients such as glucose, leucine and KCl. This effect was detected both in the early and the sustained secretory phases but was much more pronounced in the early phase. We conclude that CPX I plays a critical role in β-cells in the control of the stimulated-exocytosis of insulin.