Figure 4.

Histochemical staining of third-instar larvae. The strains represented are Canton-S (wildtype Adh^S allele; a), Adh^fn6 (null Adh allele; b), P[^m>] 82E (c), P[^a>] 82E (d), P[^m>] 99B (e), P[^a>] 99B (f), P[^m>] 67A (g), and P[^a>] 67A (h). In a, the gastric ceca are marked by an arrow. Strain 82E is consistently among the lowest-expressing strains for both P[^m>] and P[^a>] derivatives in male and female larvae and adults. Nevertheless, expression of both species’ genes is readily apparent in the gastric ceca, as it is in strains 82C, 84E, 96C, and 96F (not shown). In contrast, expression in the gastric ceca is abolished in the 99B and 67A lines.