Project/Area Number |
09670002
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
General anatomy (including Histology/Embryology)
|
Research Institution | Chiba University |
Principal Investigator |
SHIMADA Yutaka School of Medicine, Chiba University Professor, 医学部, 教授 (70009116)
|
Co-Investigator(Kenkyū-buntansha) |
KOMIYAMA Msatoshi School of Medicine, Chiba University Research Associate, 医学部, 助手 (70175339)
YOYOTA Naoji School of Medicine, Chiba University Lecturer, 医学部, 講師 (00188822)
|
Project Period (FY) |
1997 – 1999
|
Project Status |
Completed (Fiscal Year 1999)
|
Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 1999: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1998: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1997: ¥1,500,000 (Direct Cost: ¥1,500,000)
|
Keywords | myofibril / stress fiber / actin / myosin / nebulin / α-actinin / connectin / myomesi / 心筋 / 線維芽細胞 / ネプリン / 骨格筋 / 発生 / 筋蛋白質 / アイソフォーム / 筋原繊維 |
Research Abstract |
1. Developmental relationship of myosin binding proteins to myosin during myofibrillogenesis : Immunofluorescence microscopy of embryonic skeletal muscle revealed that myomesin, connectin and C-protein play an important role for assembly and regular alignment of myosin molecules. It has also been suggested that a mechanism works to remore transiently expressed embryonic isoforms (non-muscle actin and cardiac C-protein) from functional structures after they play some unknown role(s) for structure formation. 2. Dynamics of actin during myofibrillogenesis : Rhodamine (rh)-labeled actin was microinjected into cultured skeletal muscle cells and stained with anti-nebulin and anti-connectin. It was found that nebulin plays an important role for incorporaton of actin into and exchange of actin in nascent myofibrils, but connectin does not have such a role. This was confirmed by injection of anti-nebulin and anti-connectin to rh-actin injection. 3. Dynamics of actin and α-actinin in myofibrils and stress fibers: Co-injection of fluorescently labeled actin and α-actinin into cultured cardiomyocytes revealed difference in exchangeability between both proteins in developing myofibrils. This difference seems to be related to the formation of I-Z-I structure of myofibrils. Exchangeability of bothproteins in stress fibers of fibroblasts was high, and thus myofibrils and stress fibers are different structures although they are similar in appearance and composition.
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