| Project/Area Number |
13670689
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Circulatory organs internal medicine
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| Research Institution | The University of Tokyo |
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Principal Investigator |
YAMASHITA Hiroshi University of Tokyo, Graduate School of Medicine, Reseach Associate, 医学部附属病院, 助手 (50323572)
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| Co-Investigator(Kenkyū-buntansha) |
SATA Masataka University of Tokyo, Graduate School of Medicine, Reseach Associate, 医学部附属病院, 助手 (80345214)
SUGIURA Seiryo University of Tokyo, Graduate School of Frontier Sciences, Professor, 大学院・新領域創成科学研究科, 教授 (10272551)
青柳 昭彦 東京大学, 医学部・附属病院, 助手 (10251240)
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| Project Period (FY) |
2001 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥3,800,000 (Direct Cost: ¥3,800,000)
Fiscal Year 2002: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2001: ¥3,100,000 (Direct Cost: ¥3,100,000)
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| Keywords | cardiac myosin / myosin light chain / in vitro motility assay / 筋収縮 / 分子生物学 / ミオシン / カルシウムイオン / アデノウイルス / カーボンファイバー / 心筋 |
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| Research Abstract |
A myosin molecule consists of two heavy chains and two pairs of light chains and converts chemical energy of ATP hydrolysis into mechanical work of muscle contraction. The light chains are located close to the heavy chain head domain which contains ATP- and actin-binding sites essential for the motor function. To study functional roles of the myosin light chains, we purified two cardiac myosins with identical heavy chain and different light chains and compared the motor function of these myosins using in vitro motility assay techniques, where mechanical interaction of actin and myosin was reconstituted in vitro. Although catalytic activity showed no difference, motor function of these myosin molecules showed remarkable difference : the myosin molecules with ventricular-type light chains generated higher average force compared to those with atrial-type light chains and had longer duration of force-generating interaction with actin, suggesting that the myosin light chains may play an important role in converting the chemical energy into mechanical work. The unique nature of the myosin light chain modifying force-generating ability of the molecule without changing ATP hydrolysis rate may provide a clue to novel treatment for heart failure augmenting contractile function without increasing ATP consumption and protecting cardiac muscles from deterioration in energy metabolism.
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