Detailed analysis of the ATPase activity of Chara myosin

• Project/Area Number: 16570153
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Cell biology
• Research Institution: Chiba University
• Principal Investigator: YAMAMOTO Keiichi Chiba University, Faculty of Science, Professor, 理学部, 教授 (70053361)
• Co-Investigator(Kenkyū-buntansha): ITO Kohji Chiba University, Faculty of Science, Research Associate, 理学部, 助手 (50302526)
• Project Period (FY): 2004 – 2005
• Project Status: Completed (Fiscal Year 2005)
• Budget Amount: ¥3,600,000 (Direct Cost: ¥3,600,000); Fiscal Year 2005: ¥1,500,000 (Direct Cost: ¥1,500,000); Fiscal Year 2004: ¥2,100,000 (Direct Cost: ¥2,100,000)
• Keywords: myosin / motor protein / ATP hydrolysis / stopped flow / cytoplasmic streaming / 車軸藻ミオシン / ATP加水分解活性 / ストップトフロー法

Research Abstract

Chara corallina myosin is the fastest molecular motor protein known so far. To investigate the molecular mechanism of the fast movement, we determined the time of the strongly bound state with actin by measuring transient kinetic parameters of a recombinant motor domain construct of Chara myosin. The rate constant of ADP dissociation from acto-motor domain was 1,920 s^<-1>. The rate constant of ATP-induced dissociation of the motor domain from actin was 4.0 μM^<-1> s^<-1> at 25℃, which leads to an estimate of the rate constant of 6,000 s^<-1> at physiological ATP concentration. From these data, the time spent in the strongly bound state with actin was estimated to be 0.69 ms. This value is the shortest among known values for various myosins. This short strongly bound state most likely accounts for the fast motility.

Research Products

• [Journal Article] The Motility of Chara corallina Myosin was Inhibited Reversibly by 2,3-Butanedione Monoxime (BDM). (2004)
  • Author(s): Keisuke Funaki
  • Journal Title: Plant Cell Physiol 45 Pages: 1342-1345
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Importance of the Converter Region for the Motility of Myosin as Revealed by the Studies on Chimeric Chara Myosins. (2004)
  • Author(s): Masaya Seki
  • Journal Title: J. Mol. Biol 344 Pages: 311-315
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Motility of Chara corallina Myosin was Inhibited Reversibly by 2,3-Butanedlone Monoxime (BDM). (2004)
  • Author(s): Keisuke Funaki, Ayumi Nagta, Yuka Akimoto, Kiyo Shimada, Kohji Ito, K, Keiichi Yamamoto
  • Journal Title: Plant Cell Physiol. 45(9) Pages: 1342-1345
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Importance of the Converter Region for the Motility of Myosin as Revealed by the Studies on Chimeric Chara Myosins. (2004)
  • Author(s): Masaya Seki, Taku Kashiyama, You Hachikubo, Kohji Ito, Keiichi Yamamoto
  • Journal Title: J.Mol.Biol. 344 Pages: 311-315
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] The Motility of Chara corallina Myosin was Inhibited Reversibly by 2,3-Butanedione Monoxime (BDM). (2004)
  • Author(s): Keisuke Funaki, Ayumi Nagta, Yuka Akimoto, Kiyo Shimada, Kohji Ito, Keiichi Yamamoto
  • Journal Title: Plant Cell Physiol 45 ・ 9 Pages: 1342-1345
  • NAID: 10013735166
• [Journal Article] Importance of the Converter Region for the Motility of Myosin as Revealed by the Studies on Chimeric Chara Myosins (2004)
  • Author(s): Masaya Seki, Taku Kashiyama, You Hachikubo, Kohji Ito, Keiichi Yamamoto
  • Journal Title: J.Mol.Biol. 344 Pages: 311-315
• [Journal Article] Kinetic analysis of the fastest motor protein, Chara corallina myosin
  • Author(s): K.Ito, M.Ikebe, T.Kashiyama, T.Kon, T.Mogami, K.Yamamoto
  • Journal Title: Proc.Natl.Acad.Sci.USA (投稿中)
• [Book] 分子細胞生物学 第5版 (2005)
  • Author(s): 石浦章一, 石川 統, 須藤和夫, 野田春彦, 丸山工作, 山本啓一共訳
  • Total Pages: 918
  • Publisher: 東京化学同人
  • Description: 「研究成果報告書概要(和文)」より