Minimum structural unit required for energy transduction in muscle.

T Yanagida; Y Harada

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PubMed · 3407516

Minimum structural unit required for energy transduction in muscle.

T Yanagida·Y Harada

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Abstract

The sliding of actin filaments was directly measured along single-headed myosin filaments on which the density of the heads was widely varied, using video-fluorescence microscopy. The results showed that the double-headed structure of myosin is not essential for inducing the sliding movement of actin filaments. The minimum number of myosin heads required for supporting movement of actin filaments at a maximum velocity of 5 micron/s at 23 degrees C was estimated to be 4, at most 16. This led to the conclusion that the sliding distance of actin filaments induced during a single ATP hydrolysis cycle is probably 160 nm or more, at least 40 nm under unloaded conditions.

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Actin Cytoskeleton Actins Adenosine Diphosphate Adenosine Triphosphate Animals Cytoskeleton Microscopy, Fluorescence Models, Biological Muscles Myosins Rabbits Journal Article

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T Yanagida, Y Harada. 1988. Minimum structural unit required for energy transduction in muscle.. https://pubmed.ncbi.nlm.nih.gov/3407516/

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