Fig. 4.

Schematic of P{w^a} element inserted into sd.(A) P{w^a} structure. Solid black rectangles indicate P ends. A copia retrotransposon (white) ending in LTRs (black rectangles with arrows) is inserted in the second intron of the white gene (gray). (B) Structure of sd. A map of sd exons (black boxes) is shown, with the three known transcripts depicted below. Coding start sites are marked with an asterisk; sd-RB begins at the end of the third exon, and sd-RA and -RC begin at the end of the fourth exon. The insertion site for P{w^a} is indicated by the dashed line.