Fig. 2. A slow transformation of adult form occurs following prolonged perturbation of smedbmp4-1 signaling. Control unc-22(RNAi) animals are shown on the left, or top, of each set of images. (A) unc-22(RNAi) and smedsmad4-1(RNAi) animals were pictured following ten dsRNA treatments and 83 total days of treatment. smedbmp4-1(RNAi) and smedolloid-1(RNAi) animals were pictured following seven dsRNA treatments and 65 days of total treatment. smedolloid-1(RNAi) animals display dorsal tissue ruffling (white arrow), and smedsmad4-1 and smedbmp4-1(RNAi) animals display extra photoreceptors (yellow arrows). Anterior, left. Scale bars: 0.1 mm. (B) Magnification of fixed animals shows the extra photoreceptors in smedsmad4-1(RNAi) (126 days of RNAi) and smedbmp4-1(RNAi) (104 days of RNAi) animals. Anterior, up. (C-E) smedsmad4-1(RNAi) animals were fixed 126 days following initial dsRNA exposure and smedbmp4-1(RNAi) animals were fixed 104 days following initial dsRNA exposure. Anterior, left. Scale bars: 0.1 mm. (C,D) Animals were labeled with antibodies that recognize the photoreceptor neurons (VC-1, anti-Arrestin) and the cephalic ganglia (SYT, anti-Synaptotagmin). (D) Extra ventral nerve cords (green, vnc2) were present in a smedsmad4-1(RNAi) animal, located dorsal to the original nerve cords (red, vnc1). Animals were imaged with Zeiss Apotome-based optical sectioning, and the two sets of nerve cords false-colored. The regions shown are in the posterior of the animals. (E) In situ hybridizations with the smedbmp4-1 riboprobe. smedsmad4-1(RNAi) animals had no detectable smedbmp4-1 expression. (F) Animals were labeled with an antibody that recognizes cilia (anti-acetylated tubulin). The dorsal surface of smedsmad4-1(RNAi) animals display ventral-like cilia. The smedbmp4-1(RNAi) animals were fixed 117 days following initial exposure to dsRNA. Anterior, left. Scale bars: 0.05 mm.