RRC ID 45513
Author Tsuboi T, Fukuda M.
Title Rab3A and Rab27A cooperatively regulate the docking step of dense-core vesicle exocytosis in PC12 cells.
Journal J Cell Sci
Abstract Recent studies have suggested that two small GTPases, Rab3A and Rab27A, play a key role in the late steps of dense-core vesicle exocytosis in endocrine cells; however, neither the precise mechanisms by which these two GTPases regulate dense-core vesicle exocytosis nor the functional relationship between them is clear. In this study, we expressed a number of different Rab proteins, from Rab1 to Rab41 in PC12 cells and systematically screened them for those that are specifically localized on dense-core vesicles. We found that four Rabs (Rab3A, Rab27A, Rab33A, Rab37) are predominantly targeted to dense-core vesicles in PC12 cells, and that three of them (Rab3A, Rab27A, Rab33A) are endogenously expressed on dense-core vesicles. We further investigated the effect of silencing each Rab with specific small interfering RNA on vesicle dynamics by total internal reflection fluorescence microscopy in a single PC12 cell. Silencing either Rab3A or Rab27A in PC12 cells significantly decreased the number of dense-core vesicles docked to the plasma membrane without altering the kinetics of individual exocytotic events, whereas silencing of Rab33A had no effect at all. Simultaneous silencing of Rab3A and Rab27A caused a significantly greater decrease in number of vesicles docked to the plasma membrane. Our findings indicate that Rab3A and Rab27A cooperatively regulate docking step(s) of dense-core vesicles to the plasma membrane.
Volume 119(Pt 11)
Pages 2196-203
Published 2006-6-1
DOI 10.1242/jcs.02962
PII jcs.02962
PMID 16684812
MeSH Animals Cell Membrane / drug effects Cell Membrane / metabolism Cells, Cultured Exocytosis / drug effects Exocytosis / physiology* PC12 Cells RNA, Small Interfering / pharmacology Rats Secretory Vesicles / drug effects Secretory Vesicles / physiology rab GTP-Binding Proteins / antagonists & inhibitors rab GTP-Binding Proteins / biosynthesis rab GTP-Binding Proteins / physiology* rab27 GTP-Binding Proteins rab3A GTP-Binding Protein / antagonists & inhibitors rab3A GTP-Binding Protein / biosynthesis rab3A GTP-Binding Protein / physiology*
IF 4.517
Times Cited 129
DNA material pEGFP-C1-mouse Rab8A (RDB14273) pEGFP-C1-mouse Rab10 (RDB14274) pEGFP-C1-mouse Rab29 (RDB14974) pEGFP-C1-mouse Rab20 (RDB15729) pEGFP-C1-Rab41 (RDB15976) pEGFP-C1-Rab1A (RDB17236) pEGFP-C1-Rab2A (RDB17238) pEGFP-C1-Rab3A (RDB17240) pEGFP-C1-Rab4A (RDB17244) pEGFP-C1-Rab5A (RDB17246) pEGFP-C1-Rab6A (RDB17249) pEGFP-C1-Rab7 (RDB17253) pEGFP-C1-Rab9A (RDB17255) pEGFP-C1-Rab11A (RDB17257) pEGFP-C1-Rab12 (RDB17259) pEGFP-C1-Rab13 (RDB17260) pEGFP-C1-Rab14 (RDB17261) pEGFP-C1-Rab15 (RDB17262) pEGFP-C1-Rab17 (RDB17263) pEGFP-C1-Rab18 (RDB17264) pEGFP-C1-Rab19 (RDB17265) pEGFP-C1-Rab21 (RDB17266) pEGFP-C1-Rab22A (RDB17267) pEGFP-C1-Rab23 (RDB17269) pEGFP-C1-Rab24 (RDB17270) pEGFP-C1-Rab25 (RDB17271) pEGFP-C1-Rab26 (RDB17272) pEGFP-C1-Rab27A (RDB17273) pEGFP-C1-Rab28 (RDB17275) pEGFP-C1-Rab30 (RDB17276) pEGFP-C1-Rab32 (RDB17277) pEGFP-C1-Rab34 (RDB17278) pEGFP-C1-Rab36 (RDB17279) pEGFP-C1-Rab37 (RDB17280) pEGFP-C1-Rab38 (RDB17281) pEGFP-C1-Rab39A (RDB17282) pEGFP-C1-Rab40A (RDB17284)