Knockdown of crebA inhibits expression of secretory genes. (A-F) Injection of siRNAs targeting crebA (siRNA-1, center; siRNA-2, right) resulted in significantly reduced transcript levels of secretory genes in the embryonic salivary gland, including: (A) sec63, (B) spase22-23, (C) sec 71, (D) sec 24, (E) sage, (F) srp54. Injection of scrambled control siRNA-1 (left) did not impact levels of any of the transcripts examined. Dorsal views oriented anterior left are shown in all figures. Embryos range in age from 65 to 70 h. These results identify CrebA as a key regulator of Ae. aegypti secretory genes in the developing salivary gland.