9730038 Maughan The overall goal of the proposed research by Drs. Maughan and Vigoreaux is to understand the molecular basis of the high power output of insect flight muscle, using Drosophila melanogaster as the experimental organism. The PIs postulate that the extended N-terminal amino acid sequence of a regulatory protein (the myosin regulatory light chain, or RLC) on the motor molecule of muscle plays a key role in the amplification of its stretch activation response. By helping to understand the relationship between structure and function of the myosin regulatory light chain in Drosophila, this study will help advance our understanding of the molecular basis of muscle contraction and enhanced power output.