| Project/Area Number |
13670130
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
General medical chemistry
|
|---|
| Research Institution | DOKKYO UNIVERSITY SCHOOL OF M;EDICINE |
|---|
Principal Investigator |
SHIRATAKI Hiromichi The Division of Molecular and Cell Biology, Institute of Medical Science, Professor, 医学部, 教授 (90249962)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NOGAMI Satoru The Division of Molecular and Cell Biology, Institute of Medical Science, Research Assistant, 医学部, 助手 (60332996)
|
|---|
| Project Period (FY) |
2001 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2002: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 2001: ¥2,200,000 (Direct Cost: ¥2,200,000)
|
|---|
| Keywords | Raft / SNARE / Syntaxin / Taxilin / α-fodrin / Cytoskelton / Coiled-coil domain / SNARE系 / 細胞内小胞輸送 |
|---|
| Research Abstract |
Accumulating evidence suggests that formation of microdomains on the plasma membrane is an important process for intracellular signal transduction. Especially, the formation of raft is essential for intracellular signal transduction through GPI-anchored proteins. It has been previously revealed that syntaxin-3, a component of the SNARWE machinery, is implicated in the formation of raft through the regulation of intracellular vesicle transport. However, the molecular mechanism by which the formation of raft is regulated by syntaxin-3 is obscure. Then, in this study, we attempted to identify new syntaxin-3-interacting molecules. We revealed that α-fodrin, a major component of the submembranes cytoskelton, interacted with syntaxin-3. α-Fodrin bound to syntaxin-1 and syntaxin-4 as well as syntaxin-3 but no to syntaxin-7 or -8. α-Fodrin and nc18 or SNAP-25 mutually interacted with syntaxin-1. These results indicate that the formation of the SNARE complex is regulated by α-fodrin and suggest that actin/fodrin meshworks beneath the plasma membrane are involved in the formation of raft. Moreover, we identified a novel syntaxin-binding protein and named it Taxilin. Taxilin was a protein with a calculated Mr of 61,890 and 546 amino acids. Taxilin had an extraordinarily long coiled-coil region in its C-terminal half. Taxilin bound to syntaxin-1 and -4 as well as syntaxin-3 but not to syntaxin-7 or -8. Taxilin was ubiquitously expressed. A precise function of Taxilin in intracellular vesicle transport is not known. However, since Taxilin affected Ca^<2+>-dependent exocytosis in PC12 cells, it is at least possible that Taxilin is involved in Ca^<2+>-dependent exocytosis in neuroendocrine cells. In future, we attempt to reveal precise functions of α-fodrin and Taxilin in the formation of raft.
|
