Structural mechanism of the recovery stroke in the myosin molecular motor

被引：143

作者：

Fischer, S ^{[1
]}

Windshügel, B

Horak, D

Holmes, KC

Smith, JC

机构：

[1] Heidelberg Univ, Dept Computat Biochem, Interdisciplinary Ctr Sci Comp, D-69120 Heidelberg, Germany

[2] Heidelberg Univ, Dept Computat Mol Biophys, Interdisciplinary Ctr Sci Comp, D-69120 Heidelberg, Germany

[3] Max Planck Inst Med Res, D-69120 Heidelberg, Germany

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 2005年 / 102卷 / 19期

关键词：

chemo-mechanical coupling; conformational transition; conjugate peak refinement; muscle contraction; power stroke;

D O I：

10.1073/pnas.0408784102

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

The power stroke pulling myosin along actin filaments during muscle contraction is achieved by a large rotation (approximate to 60 degrees) of the myosin lever arm after ATP hydrolysis. Upon binding the next ATP, myosin dissociates from actin, but its ATPase site is still partially open and catalytically off. Myosin must then close and activate its ATPase site while returning the lever arm for the next power stroke. A mechanism for this coupling between the ATPase site and the distant lever arm is determined here by generating a continuous series of optimized intermediates between the crystallographic end-states of the recovery stroke. This yields a detailed structural model for communication between the catalytic and the force-generating regions that is consistent with experimental observations. The coupling is achieved by an amplifying cascade of conformational changes along the relay helix lying between the ATPase and the domain carrying the lever arm.

引用

页码：6873 / 6878

页数：6

共 29 条

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