Synthesis and degradation of alcohol dehydrogenase in wild-type and Adh-null activity mutants of Drosophila melanogaster.

Both the amount and the size of alcohol dehydrogenase-like cross-reacting material was determined in 14 ethyl methanesulfonate (EMS)-induced alcohol dehydrogenase-null activity mutants. In 11 mutants cross-reacting material was found. In all cases, the amount of cross-reacting material found in the mutants was lower than that in wild-type flies. High, intermediate, and low cross-reacting material-producing mutants showed similar initial rates of incorporation of labeled amino acid into alcohol dehydrogenase-like protein, presumably reflecting similar rates of synthesis. If the rate of synthesis of cross-reacting material is the same in the mutants as in the wild type, then the different levels of cross-reacting material must be due to different rates of degradation.