Cross-bridge cycling mechanisms

Over the last twenty years biophysical work on this preparation has concentrated mainly on the elucidation of the filament structure and cross-bridge conformations (Reedy et al., 1965 Squire et al., 1977 Wray, 1979 Clarke et al., 1986 Reedy et al., 1987), and on the mechanical characterisation of various equilibrium states and of the kinetics of the cross-bridge cycle (Jewell Ruegg, 1%6 White, 1970 Tregear, 1977 Gtith et al., 1981 White Thorson, 1983). The biochemistry of ATP hydrolysis by the insect proteins has received less attention than that of vertebrate muscle proteins, primarily because of shortage of tissue, but recently aspects of the biochemical kinetics have been investigated (White et al., 1986). 

The current research priorities include elucidation of the in vivo function of proteins such as CD and CP that need not involve cross-bridge cycling, and resolving the physiological relevance of the experimental situations in which LC20 phosphorylation does not explain contraction. Another potentially fertile topic is identification of mechanisms that modulate MLCK and MLCP activities and, of equal importance, establishing their in vivo significance. 

Brenner B (1986) The cross-bridge cycle in muscle. Mechanical, biochemical, and structural studies on single skinned rabbit psoas fibers to characterize cross-bridge kinetics in muscle for correlation with the actomyosin-ATPase in solution. Basic Res Cardiol 81 (Suppll) 1-15... 

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