マイクロビームを用いた昆虫飛翔筋の進化の過程に関する構造研究

抄録

X-ray diffraction patterns were recorded from the frozen-hydrated myofibrils of insect flight muscle. X-ray microbeams, generated at the high-flux BL40XU beamline of SPring-8, were irradiated along the myofibrillar axis so that the diffraction patterns were recorded from single myofibrils (diameter, 2-3 μm) . A total of 50 insect species, covering all the major winged insect orders, were examined. The results show that insects with an asynchronous flight muscle operation have giant single-crystal type myofibrils, in which the orientations of the myofilament lattice planes are preserved along their entire length. The functional significance of having such a highly regular structure is discussed.