Functional analysis of the white + gene of Drosophila by P-factor-mediated transformation

Abstract

A 12‐kb DNA segment spanning the white⁺ (w⁺) locus of Drosophila has been inserted into a P‐transposon vector and used for P‐factor‐mediated germ‐line transformation. Several red‐eyed transformants were recovered which complement the white mutant phenotype. Analysis of the eye pigments and the interaction with the zeste mutation indicates that the w⁺ gene inserted at several new chromosomal sites is expressed normally. The tissue‐specific accumulation of w⁺ transcripts, as studied by in situ hybridization to tissue sections, is the same in transformant and wild‐type larvae. This indicates that all the genetic information specified by the w⁺ locus is contained within this 12‐kb segment of DNA. By secondary mobilization it was shown that the w⁺ sequences have been inserted as a functional P(w⁺) transposon which is capable of further transposition.