Fig. 6. Wild-type ref-2 is required for Pn.p cells to be generated and to remain unfused. ref-2 gene function was inhibited by RNAi as described in the Materials and Methods. A range of phenotypes was observed depending on the concentration of dsRNA injected. Weaker RNAi produced worms in which most of the Pn.p cells had fused (short horizontal lines), Stronger RNAi produced worms in which most of the Pn.p cells were absent from the ventral cord (A). White circles indicate unfused Pn.p cells. Pictured are data for hermaphrodites; similar phenotypes were also observed in males.