This study will investigate the processes involved in the evolution of gene regulation. The sarcomeric myosin alkali light chain gene (Mlc1) in Drosophila undergoes alternative splicing of the pre-mRNA and encodes two Mlc1 polypeptides, one of which lacks exon 5 (14 amino acids). The deficient form is unique to the indirect flight muscles which power flight. They will compare patterns of sequence variation in the regions of the Mlc1 gene that are under selective constraint in several Drosophila species and representative species of the orders Hymenoptera, Hemiptera, Lepidoptera, and Odonata. These patterns of sequence variation will reveal whether sufficient variability in splicing exists to enable measurement of evolutionary change in this system.
