Age-dependent arginine phosphokinase activity changes in male vestigial and wild-type Drosophila melanogaster.

The activity of arginine phosphokinase, an important muscle enzyme in insects, was investigated with age in vestigial-winged and wild-type Drosophila melanogaster. Identical patterns of age-dependent activity changes were observed in the vestigial-winged flies as in the wild-type, even though vestigial-winged flies exhibit a 50% mortality approximately two thirds that of the wild-type as well as being incapable of flight. Results indicate that the age-dependent changes in arginine phosphokinase activity are intrinsically regulated within the cells of the flight muscle.