siRNA-mediated knockdown of crebA . Aae crebA knockdown was confirmed through whole-mount in situ hybridization. (A, B) Lateral views of 54-h embryos. (C, D) Dorsal views of 68-h embryos. Two siRNAs targeting crebA, siRNA-1 (B) and siRNA-2 (D), resulted in loss of crebA levels throughout the entire embryo (B), including the salivary glands (D). Note that the darkened area in the head shown in (B) is normal pigmentation, not gene expression. crebA levels were not altered by injection of a scrambled control version of siRNA-1 (A, C). All panels are oriented anterior-left.