rnai is used to functionally inactivate genes in cells and whole organisms like c. elegans. the cdna coding sequence of the muscle target gene is cloned, in both the sense and antisense orientations, adjacent to a strong promoter into plasmids. in vitro transcription of both constructs using rna polymerase and rntps yields rna copies complementary to the coding and antisense sequences. these copies are allowed to anneal and are then microinjected into the gonad of c. elegans. in the developing embryos,