Sequence analysis of Theileria annulata surface protein in Chinese isolates.
OBJECTIVE
To study the TaSP polymorphism in three Chinese isolates of Theileria annulata.


METHODS
The isolates from Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region and Xinjiang Uygur Autonomous Region were cultured in RPMI 1640 medium. TaSP gene was amplified from genomic DNA extracted from schizonts using polymerase chain reaction (PCR) and sequenced. Its amino acid sequence comparison was carried out with Clustal W2 multiple sequence alignment program. Molecular component and motif prediction were performed with online servers.


RESULTS
The comparison of TaSP amino acid sequences of the three isolates showed that the central region (aa position 38-161) predicted to be the highly immunogenetic domain was polymorphic both in size and amino acid sequence, while the N-terminal (first 37 aa) and C-terminal (last 154 aa) parts were strongly conserved. Phylogenetic analysis and percentage identity revealed that the Chinese isolates were closely related to the isolates from Turkey, but quite different from those of India, Morocco and Tunisia. More importantly, variability was noticed among Chinese isolates, which caused both the location and number's differences of motif (casein kinase II phosphorylation sites) among three TaSP sequences.


CONCLUSIONS
TaSP polymorphism exists in the Chinese isolates of T. annulata.
Dang
Zhi-Sheng
ZS
Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping, Lanzhou, Gansu, 730046, China.
Luo
Jian-Xun
JX
Liu
Ai-Hong
AH
Bai
Qi
Q
Guan
Gui-Quan
GQ
Liu
Zhi-Jie
ZJ
Ma
Mi-Ling
ML
Li
You-Quan
YQ
Gao
Jin-Liang
JL
Sugimoto
Chihiro
C
Yin
Hong
H
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D015800:Protozoan Proteins / Q000235:genetics*; D016415:Sequence Alignment; D017421:Sequence Analysis; D016796:Theileria annulata / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification
D008565:Membrane Proteins; D015800:Protozoan Proteins