Fig. 2. RNA interference (RNAi) phenotypes of tbx-8 and tbx-9. (A) Wild-type adult hermaphrodite tail whip. (B) Tail region of adult hermaphrodite progeny of wild-type worm injected with dsRNA corresponding to tbx-8. These worms are indistinguishable from wild type. (C) Tail region of tbx-9(RNAi) worms. The adult hermaphrodite tail is thickened (arrow) and often has a `bobbed tail' appearance. (D) Tail region of adult hermaphrodite vab-7(e1562) animal. The tail is similar in appearance to that in (C). (E) L1 larvae from hermaphrodite mother co-injected with tbx-8 and tbx-9 dsRNA. In addition to thickening of the tail, these animals display gross midbody and posterior morphological abnormalities, often with large dorsal bulges (arrow). Most die as unelongated embryos or short L1s. (F) Wild-type L1. Scale bars, 10 µm. Posterior is to the right and dorsal is up in all panels. (G) RT-PCR analysis of tbx-8 and tbx-9 transcripts in wild-type worms and those subjected to tbx-8 and tbx-9 RNAi. ama-1 was chosen as a suitable control, as mRNA would be expected to be constant throughout. For each gene, primers were chosen to specifically amplify mRNA of approximately 200 bp (see Materials and methods). Results were identical for three separate experiments.