| 摘要: |
| 【目的】研究新疆猪繁殖与呼吸综合征病毒(PRRSV)的遗传变异情况。【方法】提取PRRSV感染病猪肺脏RNA，通过RT-PCR方法对PRRSV NSP2部分基因和ORF5基因进行扩增、克隆和测序，分析其分子变异特征。【结果】成功克隆到1株PRRSV，命名为XJzx1株，其NSP2基因编码蛋白第472～476位存在5个氨基酸的连续缺失，有别于高致病毒株第482、533～561位30个氨基酸的典型缺失，位于经典毒株HB-2(sh)/2002第471～482位12个氨基酸缺失区域内；XJzx1与HK13株NSP2部分基因核苷酸序列相似性最高，为87.5%，系统进化树分析显示，XJzx1株与我国高致病毒株JXA1、HUN4、SX2009等同属一个分支；XJzx1 ORF5基因与我国经典毒株CH-1a、BJ-4、HK6等同属一个分支，其GP5蛋白不存在氨基酸的缺失或插入，而表现为多位点的突变。【结论】PRRSV XJzx1株具有独特的遗传进化特征，其毒性较经典毒株有所加强，推测为新型变异株。 |
| 关键词: PRRSV NSP2基因缺失 GP5基因 序列分析 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目（30960276，31360589） |
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| Genetic variation analysis of a porcine reproductive and respiratory syndrome virus strain with 5 amino acids deletion in NSP2 protein |
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ZHANG Xun,ZHAO Qingliang,YANG Sufang,et al
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| Abstract: |
| 【Objective】This study investigated the genetic variation of porcine reproductive and respiratory syndrome virus (PRRSV) in Xinjiang province.【Method】The total RNA was extracted from PRRSV infected lung tissue.Then the partial NSP2 gene and ORF5 gene of PRRSV were amplified, cloned and sequenced with RT-PCR.【Result】A PRRSV strain was cloned,named XJzx1,with continuous 5 amino acids deletion in 472－476 position of NSP2 within the 12 amino acids continuous deletion in 471－482 of HB-2(sh)/2002 classical PRRSV strain.It was different from the 30 amino acids deletion in 482 and 533－561 of highly pathogenic PRRSV strain.The partial NSP2 genes of XJzx1 and HK13 had highest similarity,sharing 87.5% identity of the nucleotide.Phylogenetic tree analysis revealed that XJzx1 had closer relationship with JXA1,HUN4,and SX2009 highly pathogenic strains.The ORF5 gene of XJzx1 had a few site mutations but no deletion and phylogenetic tree analysis revealed that XJzx1 had closer relationship with the CH-1a,BJ-4,and HK6 classical PRRSV strains.【Conclusion】PRRSV XJzx1 strain had special genetic mutation characteristics and higher pathogenicity than classical PRRSV,indicating that it is a new genetic subtype. |
| Key words: PRRSV deletion in NSP2 gene GP5 gene sequence analysis |
