TARGETING OF AN ENHANCER TRAP TO VESTIGIAL

The vestigial gene (vg(+)) is required for normal wing development and is expressed in a spatially distinct pattern in imaginal discs. We ha ve exploited a general property of P element alleles to target an enha ncer trap to the 5' region of the gene. By replacing the P element res ident at this site in vg(21) with a P element carrying a lacZ reporter gene, the vg(lacZ1) allele was selected on the basis of its increased mutant phenotype. In contrast to vg(+) expression, which occurs prima rily in the presumptive wing margin and hinge, beta-galactosidase expr ession in vg(lacZ1) wing discs is localized to the dorsal wing surface and displays homologous haltere expression. The targeting of P elemen t enhancer traps could be readily extended to other genes with low rat es of primary P element insertion. (C) 1994 Academic Press, Inc.