肌肉蛋白质——它们的作用与相互作用。

Muscle proteins--their actions and interactions.

作者信息

Holmes K C

机构信息

Max Planck Institut für medizinische Forschung, Heidelberg, Germany.

出版信息

Curr Opin Struct Biol. 1996 Dec;6(6):781-9. doi: 10.1016/s0959-440x(96)80008-x.

DOI:10.1016/s0959-440x(96)80008-x

PMID:8994878

Abstract

Muscle contracts by the myosin cross-bridges "rowing' the actin filaments past the myosin filaments. In the past year many structural details of this mechanism have become clear. Structural studies indicate distinct states for myosin S1 in the rigor, ATP or "down' conformation and in the products complex (ADP.Pi) or "up' to state. Crystallographic studies substantiate this classification and yield details of the transformation. The isomerization "up' to "down' is the power stroke of muscle. This consists in the main of large changes of angle of the "lever arm' (at the distal part of the myosin head) which can account for an 11 nm power stroke.

摘要

肌肉通过肌球蛋白横桥“划动”肌动蛋白丝使其滑过肌球蛋白丝而收缩。在过去的一年里，这一机制的许多结构细节已经明晰。结构研究表明，肌球蛋白S1在僵直、ATP或“向下”构象以及产物复合物（ADP·Pi）或“向上”状态下呈现出不同的状态。晶体学研究证实了这种分类，并给出了转变的细节。从“向上”到“向下”的异构化是肌肉的动力冲程。这主要包括“杠杆臂”（在肌球蛋白头部远端）角度的大幅变化，这可以解释11纳米的动力冲程。