| Project/Area Number |
14571780
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Functional basic dentistry
|
|---|
| Research Institution | The Nippon Dental University |
|---|
Principal Investigator |
IMAI Akane The Nippon Dental University, School of Dentistry at Niigata, Associated professor, 新潟歯学部, 講師 (60180080)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NASHIDA Tomoko The Nippon Dental University, School of Dentistry at Niigata, Associated professor, 講師 (10133464)
SHIMOMURA Hiromi The Nippon Dental University, School of Dentistry at Niigata, Professor, 教授 (40139259)
YOSHIE Sumio The Nippon Dental University, School of Dentistry at Niigata, Professor, 教授 (30095278)
|
|---|
| Project Period (FY) |
2002 – 2004
|
| Project Status |
Completed (Fiscal Year 2004)
|
| Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2004: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2003: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2002: ¥1,800,000 (Direct Cost: ¥1,800,000)
|
|---|
| Keywords | parotid gland / secretory granule / Munc18 / syntaxin / Rab27 / Slac2-c / Slp4-a / amylase release / Munc18-3 / SNARE / Rabタンパク質 / VAMP / 細胞内局在 / 相互作用 |
|---|
| Research Abstract |
Small GTPase Rab is a large family of putative membrane trafficking proteins, and each member is thought to regulate a specific type(s) of membrane trafficking. However, little is known about the involvement of Rab protein(s) in secretory granule exocytosis in exocrine cells or the molecular mechanism underlying this process. Here we show that Rab27B, a closely related isoform of Rab27A that regulates lysosome-related granule exocytosis in cytotoxic T lymphocytes, is abundantly expressed on amylase-containing secretory granules in rat parotid gland acinar cells. We also identify the putative Rab27B effector protein, Slac2-c (Slp homologue lacking C2 domains-c)/MyRIP, which was originally described as a myosin Va/VIIa and actin binding protein, in rat parotid glands. The results of subcellular fractionation, immunoprecipitation, and immunohistochemical studies indicate that the Rab27B-Slac2-c complex is formed on secretory granules in vivo. The introduction of either a specific Rab27 binding domain (i.e., a recombinant Slp homology domain of Slac2-b that specifically binds Rab27A/B but not other Rabs) or functionally blocking antibodies that specifically disrupt Rab27B-Slac2-c complex in vitro strongly inhibited isoproterenol-stimulated amylase release from streptolysin O-permeabilized parotid acinar cells. Our results indicate that the Rab27B-Slac2-c complex is an important constituent of secretory granule exocytosis in parotid acinar cells.
|
