Environmental factors affecting the quantity of alcohol dehydrogenase in Drosophila melanogaster

Abstract

THE alcohol dehydrogenase gene in Drosophila melanogaster has recently been the subject of intense study because it has properties that make it almost ideal for the investigation of genetic fine structure and control in a higher eukaryote^1–3, and for research on the population genetics of enzyme polymorphism^4,5. There have been reports of genetic variation in alcohol dehydrogenase activity within and between electromorphs^5–10, and of a putative control mutant with half the ‘normal’ activity¹¹. The studies described here show that environmental factors can change the amount of ADH protein in a fly by at least fourfold. They invalidate conventional methods of correcting for body size in studies of the activities and amounts of enzymes in Drosophila, and therefore cast doubt on much recent work. They also raise the possibility of an inducible eukaryotic enzyme that is suitable for refined genetic analysis.