FIG. 1.

Drosophila 90F (Ada2a) and 84F (Ada2b) chromosomal regions. Both Ada2 genes are transcribed from right to left, and their exon-intron structures are indicated. The adjacent genes and the positions of P elements in the lines l(3)S096713 and EP(3)3412 are also shown. The positions and extensions of deletions generated by mobilization of these P elements are indicated in base pairs. Heavy lines indicate fragments used to generate transgenes for the phenotypic rescue of Ada2a and Ada2b mutants.