• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Fluctuation analysis of actin in vitro sliding along native thick filaments from molluscan smooth muscles

Research Project

Project/Area Number 09480178
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Research Field Biophysics
Research InstitutionKYUSHU UNIVERSITY

Principal Investigator

TAWADA Katsuhisa  Kyushu Univ., Faculty of Science, Professor, 理学部, 教授 (20029507)

Co-Investigator(Kenkyū-buntansha) YAMADA Akira  Communication Research Laboratory, Kansai Advanced Research Center, Senior Resea, 通信総合研究所関西支所, 主任研究員
SEKIMOTO Ken  Kyoto Univ., Yukawa Institute for Theoretical Physics, Professor, 基礎物理学研究所, 教授 (00179342)
Project Period (FY) 1997 – 1998
Project Status Completed (Fiscal Year 1998)
Budget Amount *help
¥13,600,000 (Direct Cost: ¥13,600,000)
Fiscal Year 1998: ¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 1997: ¥11,000,000 (Direct Cost: ¥11,000,000)
Keywordsprotein motors / myosin / actin / sliding movement / sliding distance / fluctuation analysis / central limit theorem / ミリオン / 分子モータ / ムラサキイガイ / ミオシン繊維 / ハックスレ-・モデル
Research Abstract

1) We purified long myosin thick filaments from molluscan smooth muscles, in which myosin motors are well oriented, and we recorded sliding movements of many actin filaments with various lengths along individual myosin thick filaments in vitro. We obtained good recordings with five different myosin thick filaments.
2) We analyzed the fluctuation of the sliding distance of actin filaments, by calculating the variance of the sliding distance for a given period of time. The analysis yields a value of an effective diffusion coefficient, Din, for each actin filament. We then studied dependence of Dm on the actin filament length, and found that Dm does not depend on the actin length and is constant, as was previously found with randomly oriented motor proteins in vitro.
3) It is often believed that the actions of motor proteins in driving a cytoskeletal filament to slide unidirectionally are statistically independent and random. If this is the case, we can expect that Dm is proportional to the inverse of the actin filament length, which is a direct consequence of the central limit theorem. By computer simulation with Huxley's 1957 model of 'spring myosins' we confirmed this theoretical prediction that the fluctuation of sliding distance is proportional to the inverse of the filament length if the motor actions are random and statistically independent.
4) However, the above experimental finding that Din does not depend on the actin filament length indicates that this belief does not hold in the case of the in vitro sliding movement generation by protein motors, and instead indicates that there is a cooperativity in the mechanism of the directional sliding movement generation by motor proteins.
5) We therefore conclude that the actions of myosin motors in generating the unidirectional sliding movement of actin filaments are not random and there must be cooperativity in their actions. We are currently studying possible mechanisms of the cooperativity by computer simulation.

Report

(3 results)
  • 1998 Annual Research Report   Final Research Report Summary
  • 1997 Annual Research Report
  • Research Products

    (17 results)

All Other

All Publications (17 results)

  • [Publications] Imafuku,Y.,Toshima,Y.Y., & Tawada,K.: "Length-dependence of displacement fluctuation and velocity in microtubule sliding movement driven by sea urchin sperm outer beta-dynein in vitro." Biophys.Chem. 67. 117-125 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Sekimoto,K.: "Kinetic characterization of heat bath and the energetics of thermal rathet models." J.Phys.Soc.Jpn. 66. 1234-1237 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Yamada,A.,Yoshio,M. & Nakayama,H.: "Bi-directional movement of actin filaments along long bipolar tracks of oriented rabbit skeletal muscle myosin molecules." FEBS Lett.409. 380-384 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Tawada,K.,Toyoda,M.,Imafuku,Y., & Yamada,A.: "Fluctuation correlation in the sliding generated by protein motors in vitro" Advances in Exptl and Med.Biology. 453. 47-51 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Sekimoto,K.: "Langevin equation and thermodynamics" Progr.Theor.Phys.Suppl.130. 17-27 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Yamada,A.,・・・Nakayama,H. & Oiwa,K.: "Unidirectional movement of fluorescent microtubules on rows of dynein arms of disintegrated axonemes." J.Cell Sci.111. 93-98 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Imafuku, Y., Toyoshima, Y.Y.& Tawada, K.: "Length-dependence of displacement fluctuation and velocity in microtubule sliding movement driven by sea urchin sperm outer beta-dynein in vitro." Biophys.Chem.67. 117-125 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Sekimoto, K.: "Kinetic characterization of heat bath and the energetics of thermal rachet models." J.Phys.Soc.Jpn. 66. 1234-1237 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Yamada, A., Yoshio, M.& Nakayama, H.: "Bi-directional movement of actin filaments along long bipolar tracks of oriented rabbit skeletal muscle myosin molecules." FEBS Lett.409. 380-384 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Tawada, K., Toyoda, M., Imafuku, Y & Yamada, A.: "Fluctuation correlation in the sliding generated by protein motors in vitro." Advances in Exptl and Med.Biology. 453. 47-51 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Sekimoto, K.: "Langevin equation and thermodynamics" Progr.Theor.Phys.Suppl.130. 17-27 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Yamada, A., Yamaga, T., Sakakibara, H., Nakayama, H.& Oiwa, K.: "Unidirectional movement of fluorescent microtubules on rows of dynein arms of disintegrated axonemes." J.Cell.Sci.111. 93-98 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1998 Final Research Report Summary
  • [Publications] Tawada,K.,Toyoda,S.,Imafuku,Y.,&Yamada,A.: "Fluctuation correlation in the sliding movement generated by protein motors in vitro." Advances in Exptl and Med.Biology. 453. 47-51 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] Sekimoto,K.: "Langevin Equation and Thermodynamics" Progr.in Theor.Phys.Suppl.130. 17-27 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] Imafuku,Y.: "Length independence of displacement fluctuations and velocity in microtubule sliding movement driven by sea urchin sperm outer arm beta-dynein in vitro." Biophysical Chemistry. 67. 117-125 (1997)

    • Related Report
      1997 Annual Research Report
  • [Publications] Tawada,K.: "Fluctuation correlation in the sliding movement generated by protein motors in vitro." Advances in Exptl and Med.Biology. (in press). (1998)

    • Related Report
      1997 Annual Research Report
  • [Publications] 太和田勝久: "分子モータの滑り速度と分子摩擦「生体分子モータの仕組み(石渡編)」" 共立出版, 14 (1997)

    • Related Report
      1997 Annual Research Report

URL: 

Published: 1997-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi