猪繁殖与呼吸综合征病毒河南分离株的遗传变异分析

Clone and genetic variation analysis of porcine reproductive and respiratory syndrome virus of Henan isolates

用间接免疫荧光试验和RT-PCR方法，从河南省不同地区送检的疑似猪繁殖与呼吸综合征的病料中分离到16株猪繁殖与呼吸综合征病毒（PRRSV），扩增分离株的ORF5基因并进行序列测定、比较分析和绘制进化树．结果表明，16株分离株之间的氨基酸序列同源性为88．1％～99，8％；与欧洲型LV株和美洲型VR-2332株的氨基酸序列同源性分别为54．0％～54．5％和88．1％～99．2％，证明分离的16株病毒均为美洲型．用DNAstar等软件对16株分离株推导的氨基酸序列作进一步比较分析，发现16株分离株ORF5基因编码的gp5蛋白的抗原区、潜在疏水区、跨膜区和N-糖基化位点分布均有差异，与其它美洲型毒株也存在一定程度的差异，说明在河南流行的PRRSV存在明显的遗传差异性．

Using the indirect immunity fluorescence experiment and the RT-PCR identification, we obtained 16 PRRSV strains, which came from the doubtful porcine reproductive and respiratory syndrome materials of different areas of Henan Province. The ORF5 gene of strains was amplified the sequence determination and the comparative analysis and the cladogram was drawn up. The results indicated that 16 strains between the amino acid sequence homology was 88. 1% - 99.8%. Comparing 16 strains with Europe an LV and the American VR-2332, the amino acid sequence homology was 54.0% -54.5% and 88. 1%- 99. 2% respectively, the analysis proved separates 16 virus were American;By the software DNAstar and so on, we made the further comparative analysis 16 strains inferential reasoning amino acid sequences, discovering that the gp5 proteins coded by the ORF5, the hydrophobic regions, the antigen areas, the transmembrane domains and the N-glycosylation sites had the differences. They also had the differences with other American poisonous. The analysis explained that there were obvious heredity differences in Henan popular PRRSV.