Datensatz

Zusammenfassung

FROM structural studies on glycerinated Lethocerus flight muscle Ready, Holmes and Tregear1 showed that the cross-bridges of insect flight muscle take on recognizably different configurations in the presence and absence of ATP. In the presence of excess ATP (relaxed) the bridges are approximately at right-angles to the myosin thick filament and in its absence (rigor state, with formation of the actomyosin complex) they make a chevron-like structure by binding at an angle of about 45° to the actin filaments. Coupled with studies on living frog muscle2 this led to proposals by Huxley3 and Pringle4 that the cross-bridges move the actin filament past the myosin filament by a kind of rowing action; a model which has been generally accepted as a working hypothesis.