Abstract: 45W related genes were amplified by RT-PCR from the hatched and activated oncospheres of Taenia solium, cloned and sequenced. A total of 16 transcripts were obtained, suggesting that 45W related genes had far more than five members as previously reported. The 45W-4B clone in our study was found to be highly conversed. The protein encoded by 4B transcript would be a good candidate for the development of recombinant vaccine against cysticercosis in pigs. The modified transcripts A3E/X and B2E/X were expressed in the form of GST fusion protein in E. coli. The fusion proteins of GST-A3E/X and GST-B2E/X could not be detected using sera from humans infected with cysticercosis. Also, GST-A3E/X fusion protein could not be detected by sera raised from pigs infected with oncospheres. Transcripts of this family encode glycoproteins with a transmembrane region located at the C terminal. The secondary structures of 45W proteins were characterized with Cn-Em repeat units and a 16-17 amino acids comprised α-helix structural unit. In the processing of 45W proteins, the phosphorylated modification on which some functions are depended may be important. These results suggest that 45W proteins' functions are complicated, related with the regulation of gene expression and maintance of the cellular cytoskeleton and so on.

Key words: Taenia solium, Gene family, Oncosphere, Transcript, Structural prediction