Cloning and sequence analysis of P32 surface protein genes of three strains of bovine Theileria sergenti.

To analyze P32 gene sequence of bovine Theileria sergenti in China,a pair of primers was designed according to the T.sergenti P32 surface protein gene sequences available in GenBank.Three T.sergenti genes were amplified from T.sergenti Liaoyang strain,Ningxian strain and Wenchuan strain by PCR,and then was cloned into pGEM-T Easy vector,respectively.The positive clone was identified by PCR and restriction digestion with EcoRⅠ.Sequencing of the positive clones showed that the inserted fragment was 875 bp in total length,encoding a protein of 283 amino acids.Sequence analysis showed that the identity between Liaoyang strain and Ningxian strain was 99.4% and the identities of T.sergenti Wenchuan strain with these two isolates were 92.1% and 91.9% respectively.However the homology of T.sergenti Liaoyang strain with T.sergenti Japanese strain(AB016280) and Russian strain(AB016279) exceeded to 99.8% and 99.6%,respectively.