[Genetic control of phenoloxidase in the imago of Drosophila melanogaster].

The A1 component of Drosophila melanogaster phenol oxidase is controlled by an independent structural gene which has been located by the method of recombination mapping on the second chromosome at 67.3. The Dox-A1 is the only one from the group of genes coding for phenol oxidase in Drosophila which is expressed at the imago stage. The activity of phenol oxidase depends on the level of gene Dox-A1 expression and also on the presence in haemolymph of proenzyme activators. Males have a minimum level of phenol oxidase activity, which possibly protects them from mechanical damages of cuticle and toxic effects. Females are characterized by a higher level of A1-phenol oxidase activity than males. This may be caused by their reproduction function.