REPRESSION OF HYBRID DYSGENESIS IN DROSOPHILA-MELANOGASTER BY HEAT-SHOCK-INDUCIBLE SENSE AND ANTISENSE P-ELEMENT CONSTRUCTS

Sets of sense and antisense P-element constructs controlled by a heat- shock-inducible promoter were tested for their ability to repress mani festations of P-element activity in vivo. As a group, the antisense co nstructs repressed pupal lethality, a somatic manifestation of P activ ity, and this repression was significantly enhanced by heat shock. Thr ee of the 11 antisense constructs also repressed gonadal dysgenesis, a manifestation of P activity in the female germ line; however, none ha d any effect on P-element-mediated mutability in the male germ line. A mong the 13 different heat-shock-inducible sense constructs that were tested, those containing the KP and DP elements were strong repressors of pupal lethality, gonadal dysgenesis and P-element-mediated mutabil ity; however, individual lines carrying these constructs varied in the ir ability to repress each of these traits, presumably because of geno mic position effects. With the exception of the sense construct that c ontained a complete P element, none of the sense or antisense construc ts repressed a lacZ reporter gene driven by the P-element promoter. Ov erall, the experimental results suggest that in nature, P-element acti vity could be regulated by P-encoded polypeptides and by antisense PRN As.