Figure 2.—

Southern analysis of deletion strains. (A) The NcoI restriction map of the chromosome 3R genomic region surrounding the D1^EP473 insertion site is illustrated. The gene span of D1, with coding region in gray, and position of the D1 cDNA probe used for Southern analysis (solid line) are shown below the map. (B) Genomic DNA was isolated from w¹¹¹⁸ (lane 1), D1^EP473/+ (lane 2), D1^EP473/Df(3R)Exel6152 (lane 3), D1^EP473/Df(3R)BSC24 (lane 4), D1^EP473/Df(3R)D1^C12w− (lane 5), +/Df(3R)Exel6152 (lane 6), +/Df(3R)BSC24 (lane 7), +/Df(3R)D1^C12w− (lane 8), and D1^EP473 (lane 9), and digested with NcoI. A wild-type D1 locus was expected to yield a 3041-bp genomic fragment whereas the D1^EP473 insertion was expected to yield a 3481-bp genomic fragment. Only the D1^EP473 allele was observed when the flies were heterozygous for D1^EP473 and deletions Df(3R)Exel6152, Df(3R)BSC24, or Df(3R)D1^C12w−. In contrast, only the wild-type allele was observed when the flies were heterozygous for D1⁺ and deletions Df(3R)Exel6152, Df(3R)BSC24, or Df(3R)D1^C12w−.