Echinococcus multilocularis: cloning and characterization of a member of the SNW/SKIP family of transcriptional coregulators.

We have isolated a cDNA from the fox-tapeworm Echinococcus multilocularis that encodes EmSkip, a novel member of the SNW/SKIP family of transcriptional coregulators. EmSkip displays significant amino acid sequence homologies to already known members of the protein family and contains all the characteristic amino acid residues at their corresponding positions. RT-PCR experiments showed that the EmSkip encoding gene, emskip, is expressed in the Echinococcus larval stages metacestode and protoscolex during an infection of the intermediate host. By yeast two-hybrid analyses, EmSkip was found to be capable of forming homodimers in vivo. Furthermore, EmSkip was found to interact with EmSmadA and EmSmadB, two previously identified TGF-β/BMP signal transducers of E. multilocularis, indicating a role of this protein in TGF-β signaling processes in the parasite. In view of the role played by SNW/SKIP proteins in splicing mechanisms and intracellular signaling, the data presented herein should facilitate the identification of Echinococcus factors involved in such processes.