Glucose-induced translocation of coronin 3 regulates the retrograde transport of the secretory membrane in the pancreatic beta-cells.
GTP-Rab27a is known to regulate insulin exocytosis. We have recently reported that coronin 3, which paradoxically binds GDP-Rab27a, participates in endocytosis of the insulin secretory membrane. Here, we demonstrate that glucose stimulation caused redistribution of coronin 3 in the vicinity of the plasma membrane, which was mimicked by overexpression of the GDP-Rab27a mutant or the Rab27a GAP. Glucose-induced translocation of coronin 3 was inhibited by Rab27a knock-down. The internalized phogrin, an insulin granule associated protein, located near the plasma membrane by the dominant-negative coronin 3, but the protein at the outer surface of the plasma membrane was decreased. These results indicate that glucose recruits coronin 3 near the plasma membrane, and that it regulates the retrograde transport of the secretory membrane in pancreatic beta-cells.
Kimura
Toshihide
T
Department of Pharmacology, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita 879-5593, Japan.
Taniguchi
Shigeki
S
Toya
Kazuo
K
Niki
Ichiro
I
D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism* / Q000494:pharmacology; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008840:Microfilament Proteins / Q000378:metabolism*; D021381:Protein Transport; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism; D000075745:rab27 GTP-Binding Proteins
D008840:Microfilament Proteins; D000075745:rab27 GTP-Binding Proteins; C072061:coronin proteins; C512962:Rab27a protein, mouse; D020691:rab GTP-Binding Proteins; D005947:Glucose