Isolation of serotype 2 porcine teschovirus in China: evidence of natural recombination.
Porcine teschovirus (PTV), the pathogen of porcine polioencephalomyelitis, is a member of the family Picornaviridae. In this study, a new PTV strain (designated as JF613) was isolated from pigs in China. It was confirmed by the specific CPE on susceptible cells, RT-PCR and nucleotide sequencing. Analysis of its amino acids sequence of complete polyprotein indicated that the isolate belongs to serotype 2. Genetic recombination is a well-known phenomenon for picornavirus which has been demonstrated in many other members of the family, but it remains so far unclear whether recombination occurs in PTV. To detect possible recombination events, 30 sequences of complete coding regions of PTV strains accessible in GenBank were examined. Putative recombinant sequence was identified with the use of SimPlot program. The result showed that the genomic sequence of our isolate exhibited highest similarities with strains of serotypes 2 and 5, respectively, in two crossover regions, suggesting the recombination event in PTV. Then the mosaic structure of viral genome was confirmed by bootscanning and genetic algorithm for recombination detection (GARD). This represents the first PTV-2 isolate in China. Furthermore, our study provided the first evidence of natural recombination in PTV and indicated that homologous recombination may be a driving force in PTV evolution.
National Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 427 Maduan Street, Harbin 150001, Heilongjiang, China.
Bin
B
Wang
Zhi-Jun
ZJ
Tian
Da-Qing
DQ
Gong
Deng-Yun
DY
Li
Yao
Y
Wang
Jia-Zeng
JZ
Chen
Tong-Qing
TQ
An
Jin-Mei
JM
Peng
Guang-Zhi
GZ
Tong
D000818:Animals; D001483:Base Sequence; D002681:China / Q000453:epidemiology; D003434:Crossing Over, Genetic / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D010850:Picornaviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary; D012703:Serotyping / Q000662:veterinary; D013552:Swine / Q000821:virology; D013553:Swine Diseases / Q000453:epidemiology / Q000821:virology; D052700:Teschovirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D014774:Virulence / Q000235:genetics
D004279:DNA, Viral