An x-ray diffraction study on the ADP-induced conformational change in skeletal muscle myosin.
Effects of ADP on the conformation of myosin cross-bridges were studied in x-ray diffraction experiments on single skinned fibers of frog skeletal muscle by photorelease of ADP from caged-ADP. The experiments were performed at the third-generation synchrotron radiation facility SPring-8 with a time resolution of 5 ms. The intensity of the third-order meridional reflection from myosin filaments (at 1/14.4 nm(-1)) increased promptly after the ADP release with a time constant smaller than 5 ms, which was similar to that of tension decline. The results show that ADP binding induces a conformational change of myosin in skeletal muscle fibers.
Horiuti
Keisuke
K
Department of Physiology, Oita Medical University, Hasama, Oita 879-55, Japan.
Yagi
Naoto
N
Takemori
Shigeru
S
Yamaguchi
Maki
M
D000244:Adenosine Diphosphate / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000528:radiation effects; D000818:Animals; D008027:Light; D009119:Muscle Contraction; D018485:Muscle Fibers, Skeletal / Q000737:chemistry / Q000502:physiology; D018482:Muscle, Skeletal / Q000737:chemistry*; D009218:Myosins / Q000737:chemistry*; D009578:Nitrobenzenes / Q000528:radiation effects; D044367:Phase Transition; D011487:Protein Conformation; D011892:Rana catesbeiana; D013997:Time Factors; D014961:X-Ray Diffraction
D009578:Nitrobenzenes; C101520:P(2)-(1-(2-nitrophenyl)ethyl) ADP; D000244:Adenosine Diphosphate; D009218:Myosins