Expression and functional characterization of a Rho-family small GTPase CDC42 from Trichinella spiralis.

A full-length cDNA encoding a Rho-family small GTPase gene cdc42 of Trichinella spiralis was expressed in E. coli. The recombinant protein of TsCDC42 was purified and used to raise the polyclonal antibodies. The expression of TsCDC42 in different stages of parasite was investigated. The western blot showed that TsCDC42 was expressed in all stages of T. spiralis, including newborn larvae, muscle larvae and adult worms. The immuno-localization revealed that TsCDC42 was ubiquitously distributed in the newborn larvae, muscle larvae and adult worm. Cross-species RNAi was done by knockdown Tscdc42 RNAi in C. elegans. The results revealed that endogenous expression level of CDC42 was decreased by knockdown Tscdc42 RNAi in C. elegans, and this knockdown reduced the progeny of C. elegans. It suggested that Tscdc42 might play the same roles in the early development of T. spiralis.