Ontogeny and tissue distribution of alcohol dehydrogenase inDrosophila melanogaster

Alcohol dehydrogenase (ADH) activity inDrosophila larvae and adults is localized primarily in fat body, intestine, and Malpighian tubules. In adult males, it occurs furthermore in derivatives of the genital disk.When expressed as ADH activity/whole organism, increasing values are found throughout the larval stages. Around the time of puparium formation, the activity decreases, to increase again around hatching of the adult.As the genital disk undergoes metamorphosis, it synthesizes (or activates) ADH rather than acquiring the enzyme from elsewhere in the organism.