Project/Area Number |
10470022
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
General pharmacology
|
Research Institution | Gunma University |
Principal Investigator |
KOHAMA Kazuhiro Gunma University, School of Medicine, Department of Pharmacology, Professor, 医学部, 教授 (30101116)
|
Co-Investigator(Kenkyū-buntansha) |
NAKAMURA Akio Gunma University, School of Medicine, Department of Pharmacology, Assistant Professor, 医学部, 助手 (30282388)
ISHIKAWA Ryoki Gunma University, School of Medicine, Department of Pharmacology, Assistant Professor, 医学部, 助手 (20212863)
OKAGAKI Tsuyoshi Gunma University, School of Medicine, Department of Pharmacology, Lecturer, 医学部, 講師 (80185412)
|
Project Period (FY) |
1998 – 1999
|
Project Status |
Completed (Fiscal Year 1999)
|
Budget Amount *help |
¥13,600,000 (Direct Cost: ¥13,600,000)
Fiscal Year 1999: ¥6,600,000 (Direct Cost: ¥6,600,000)
Fiscal Year 1998: ¥7,000,000 (Direct Cost: ¥7,000,000)
|
Keywords | myosin light chain kinase / myosin / actin / smooth muscle / phosphorylation / cell motility / 遊走能 |
Research Abstract |
We constructed a plasmid vector having a 1.4-kilobase pair insert of myosin light chain kinase (MLCK) cDNA in an antisense direction to express antisense mRNA. The construct was then transfected to SM3, a cell line from vascular smooth muscle cells, producing a few stable transfectants. The down-regulation of MLCK expression in the transfectants was confirmed by both Northern and Western blots. The control SM3 showed chemotaxic motility to plastelet-derived growth factor-BB, which was supported by lamellipodia. However, the transfectants showed neither chemotaxic motility nor developed lamellipodia, indicating the essential role of MLCK in the motility. The specifity for the targeting was assessed by a few tests including the rescue experiment. Despite this importance of MLCK, platelet-derived growth factor-BB failed to induce MLC20 phosphorylation in not only the transfectants but also in SM3. MLCK of smooth muscle is multifunctional, being composed of N-terminal actin-binding domain, central kinase domain, and C-terminal myosin-binding domain. We also found that the C-terminal domain could stimulate the actin-activated ATPase activity of smooth muscle myosin without phosphorylating its light chain. We discussed that the C-terminal domain may develop the membrane ruffling.
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