Summary
X-ray diffraction patterns from frog sartorius muscle were recorded during steady shortening with various loads. The intensity of the third meridional reflection from the thick filament decreased on shortening to an extent proportional to the drop in tension. The intensity correlated more closely with the tension than with the shortening velocity. The Bragg spacing of the third meridional reflection decreased in proportion to the decrease in tension. The intensity decrease of the actin layer lines at 1/5.1 and 1/5.9 nm−1 was roughly proportional to the decrease in the load, indicating that the number of cross-bridges decreases similarly. The intensity of the (1,1) equatorial reflection showed a significant decrease only with low loads. Assuming that a steady structural state is attained during steady shortening, the results are consistent with the cross-bridge model in which the number of myosin cross-bridges decreases during shortening.
Similar content being viewed by others
References
AMEMIYA, Y., & WAKABAYASHI, K. (1991) Imaging plate and its application to X-ray diffraction of muscle. Adv. Biophys. 27, 115–28.
AMEMIYA, Y., WAKABAYASHI, K., HAMANAKA, T., WAKA-BAYASHI, T., MATSUSHITA, T. & HASHIZUME, H. (1983) Design of a small-angle X-ray diffractometer using synchrotron radiation at the photon factory. Nucl. Instr. Methods 208, 471–7.
AMEMIYA, Y., WAKABAYASHI, K., TANAKA, H. UENO, Y. & MIYAHARA, J. (1987) Laser-stimulated liminescence used to measure X-ray diffraction of a contracting striated muscle. Science 237, 164–8.
AMEMIYA, Y., IWAMOTO, H., KOBAYASHI, T., SUGI, H., TANAKA, H. & WAKABAYASHI, K. (1988) Time-resolved X-ray diffraction studies on the effect of slow length changes on tetanized frog skeletal muscle. J. Physiol. 407, 231–42.
BORDAS, J., DIAKUN, G. P., DIAZ, F. G., HARRIES, J. E., LEWIS, R. A., LOWY, J., MANT, G. R., MARTIN-FERNANDEZ, M. L. and TOWNS-ANDREWS, E. (1993) Two-dimensional time-resolved X-ray diffraction studies of live isometrically contracting frog sartorius muscle. J. Muscle Res. Cell Motil. 14, 311–24.
FORD, L. E., HUXLEY, A. F. & SIMMONS, R. M. (1985) Tension transients during steady shortening of frog muscle fibers. J. Physiol. 361, 131–40.
GRIFFITHS, P. J., ASHLEY, C. C., BAGNI, M. A., MAÉDA, Y. & CECCHI, G. (1993) Cross-bridge attachment and stiffness during isotonic shortening of intact single muscle fibers. Biophys. J. 64, 1150–60.
HASELGROVE, J. C.. (1975) X-ray evidence for conformational changes in the myosin filaments of vertebrate striated muscle. J. Mol. Biol. 92, 113–43.
HASELGROVE, J. C. & HUXLEY, H. E. (1973) X-ray evidence for radial cross-bridge movement and for the sliding filament model in actively contracting skeletal muscle. J. Mol. Biol. 77, 549–68.
HILL, A. V. (1939) The heat of shortening and the dynamic constants of muscle. Proc. Royal Soc. Lond. B126, 136–95.
HUXLEY, A. F. (1957) Muscle structure and theories of contraction. Prog. Biophys. Biophys. Chem. 7, 255–318.
HUXLEY, H. E. (1979) Time resolved X-ray diffraction studies on muscle. In Cross-bridge Mechanism in Muscle Contraction (edited by SUGI, H. & POLLACK, G. H.) pp. 391–405. Tokyo: University of Tokyo Press.
HUXLEY, H. E., KRESS, M., FARUQI, A. F. & SIMMONS, R. M. (1988) X-ray diffraction studies on muscle during rapid shortening and their implications concerning crossbridge behaviour. In Molecular Mechanism of Muscle Contraction (edited by SUGI, H. & POLLACK, G. H.) pp. 347–52. New York and London: Plenum Press.
JULIAN, F. J. & SOLLINS, M. R. (1975) Variation of muscle stiffness with force at increasing speeds of shortening. J. Gen. Physiol. 66, 287–302.
KRESS, M., HUXLEY, H. E., FARUQI, A. R. & HENDRIX, J. (1986) Structural changes during activation of frog muscle studied by time-resolved X-ray diffraction. J. Mol. Biol. 188, 325–42.
MATSUBARA, I. & YAGI, N. (1985) Movements of crossbridges during and after slow length changes in active frog skeletal muscle. J. Physiol. 361, 151–63.
PODOLSKY, R. J. (1960) Kinetics of muscular contraction: the approach to the steady state. Nature 188, 666–8.
PODOLSKY, R. J., NOLAN, A. C. & ZAVELER, S. A. (1969) Cross-bridge properties derived from muscle isotonic velocity transients. Proc. Natl Acad. Sci. USA 64, 504–11.
PODOLSKY, R. J., ST. ONGE, R., YU, L. & LYMM, R. W. (1976) X-ray diffraction of actively shortening muscle. Proc. Natl Acad. Sci. USA 73, 813–17.
ROME, E., OFFER, G. & PEPE, F. A. (1973) X-ray diffraction of muscle labelled with antibody to C-protein. Nature New Biol. 244, 152–4.
SQUIRE, J. M. (1981) The Structural Basis of Muscle Contraction. New York and London: Plenum Press.
WAKABAYASHI, K., TANAKA, H., SAITO, H., MORIWAKI, N., UENO, Y. & AMEMIYA, Y. (1991) Dynamic X-ray diffraction of skeletal muscle contraction: structural change of actin filaments. Adv. Biophys. 27, 3–13.
YAGI, N. (1992) Effects of N-ethylmaleimide on the structure of skinned frog skeletal muscles. J. Muscle Res. Cell Motil. 13, 457–63.
YAGI, N., TAKEMORI, S. & WATANABE, M. (1993) An X-ray diffraction study of frog skeletal muscle during shortening near the maximum velocity. J. Mol. Biol. 231, 668–77.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Yagi, N., Takemori, S. Structural changes in myosin cross-bridges during shortening of frog skeletal muscle. J Muscle Res Cell Motil 16, 57–63 (1995). https://doi.org/10.1007/BF00125310
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00125310