title: Small-angle X-ray scattering from myosin heads in relaxed and rigor frog skeletal muscles.
abstract: Low-angle X-ray diffraction patterns from relaxed and non-overlap rigor muscles show a central region of diffuse scattering (disk) which is circularly symmetrical, behaves as solution scattering and comes predominantly from myosin heads. In full-overlap rigor the disk is compressed in the diagonal direction, indicating that the myosin heads have a bent shape and a preferred orientation consistent with a 45 degree angle of attachment to actin.
mesh_terms: D000199:Actins / Q000502:physiology; D000818:Animals; D009119:Muscle Contraction; D009126:Muscle Relaxation; D009132:Muscles / Q000648:ultrastructure; D009218:Myosins / Q000502:physiology*; D011487:Protein Conformation; D011898:Ranidae; D014961:X-Ray Diffraction
chemical_list: D000199:Actins; D009218:Myosins