Bidirectional functional communication between myosin subfragments 1 and 2 in skeletal muscle fibers
Kobayashi, T.; Kosuge, S.; Sugi, H.
Advances in Experimental Medicine and Biology 453: 435-440
1998
ISSN/ISBN: 0065-2598 PMID: 9889855 Document Number: 487501
It has been shown that polyclonal antibody directed against myosin subfragment 2 (S-2) eliminates Ca(2+)-activated isometric force development in glycerinated skeletal muscle fibers while Mg-ATPase activity of the fibers remains unchanged. To further explore possible involvement of myosin S-2 in muscle contraction, we studied the effect of anti-S-2 antibody on rigor linkage formation in the fibers, and found that the antibody inhibited development of rigor force in a dose- and time-dependent manner without changing the relation between muscle fiber stiffness and force. If, however, the antibody was applied after development of rigor force, it had no effect on both the stiffness and force. These results strongly suggest bidirectional functional communication between myosin subfragments 1 and 2 in the fibers.