Fig. 8. nhr-25 RNAi disrupts the ultrastructure of the epidermis and molting. (A,B) Compared with a control (A), the ventrolateral hyp7 epidermis is extremely thick in nhr-25(RNAi) adult (B, double arrow), thus separating muscles from the cuticle. The fibrous organelles that normally attach muscles to the cuticle (arrows) are not apparent (B). Likewise the struts between the cuticle layers (arrowheads) are missing; instead, abnormal vesicles of unknown content are present in nhr-25(RNAi) animals (B). Bar, 2 µm. (C,D) Wild-type worms fed on nhr-25 dsRNA-expressing E. coli from the time of hatching display molting defects. Examples show unshed L4 cuticle, attached to the head (C) or causing constrictions (D) in affected adults.