Myosin filament structure and myosin crossbridge dynamics in fish and insect muscles.

Abstract

The muscle crossbridge power stroke on actin appears to involve a change in angle between the actin-attached motor domain and the neck region of the myosin heads (the ‘tilting neck hypothesis’). However, this mechanism has not been proved beyond doubt and a reasonable question to ask is how actual proof might be achieved. This is essentially a structural question. The question can be put as ‘what are the molecular shapes that the myosin head adopts during the crossbridge cycle on actin?’. A further question that also needs answering is ‘how do the biochemical stages of the actin-myosin ATPase cycle map onto the structural changes that are seen?’. The purpose of the present paper is to address how the first question might be answered and to start to make suggestions about the second.KeywordsFish MuscleMyosin HeadMotor DomainThick FilamentMyosin FilamentThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.