FPLV、CPV、MEV非结构蛋白NS1和结构蛋白VP2遗传特征分析

Genetic Characteristic Analysis of Non-structural NS1 and Structural Protein VP2 of FPLV,CPV and MEV

为了解猫泛白细胞减少症病毒(FPLV)、犬细小病毒(CPV)、水貂肠炎病毒(MEV)氨基酸遗传演化规律,探索细小病毒在不同种属动物间跨种传播过程中病毒蛋白氨基酸差异特点以及毒株流行病学特征。通过搜集确定为CPV、MEV的粪便病料,PCR扩增克隆非结构蛋白NS1和结构蛋白VP2基因,并参考GenBank中其他细小病毒毒株,对其推导的氨基酸序列构建遗传发育树,进行病毒的遗传进化分析,同时对细小病毒流行毒株的非结构蛋白NS1和结构蛋白VP2基因编码的氨基酸差异位点进行了归纳总结。遗传进化分析结果表明,细小病毒不同种属以及同种属各亚型之间NS1蛋白氨基酸同源性高于VP2蛋白,但氨基酸差异较小。FPLV和MEV NS1和VP2蛋白原本保守的氨基酸,在遗传进化的过程中出现与CPV一致的突变(NS1蛋白第247、350、545、595位氨基酸;VP2蛋白第101、232、411位氨基酸)。FPLV、MEVVP2蛋白氨基酸在进化过程中不同于CPV,但是更加稳定。我国CPV分离毒株中,CPV-2a亚型VP2蛋白Ile324位氨基酸独特位点仍然存在。

To find out the amino acid inheritance of feline panleukopenia virus （FPLV）, canine parvovirus （CPV） and mink enteritis virus （MEV）, and explore the virus amino acid variances in interspecies infection and the epidemiological characteristics, faecal samples confirmed as CPV and MEV infection were collected and used for cloning the complete ORFs genes both of non-structural protein NS1 and the main structural protein VP2 hy PCR. The phylogenetic trees of the deduced amino acid sequences of NS1 and VP2 genes were set to estimate phylogenetic relationships of virus with the reference strains. The virus a- mino acid variances were summarized. The results suggested that amino acid variances in non-structural protein NS1 in different genuses and Subtypes of parvovirus were few,while in structural protein VP2 were obvious. The homology of NS1 protein amino acids are higher than that of VP2 protein. Amino acids which are conservative in NS1 and VP2 protein of FPLV and MEV, mutated to which are in accord with CPV. ＇The evolution of VP2 genes in FPLV and MEV is different with that of CPV, and more stable than which in CPV （the amino acids of NS1 protein at the position of 247,350,545,595 and VP2 protein at the position of 101,232,411 ）. The special amino acid residue of Ile324 of VP2 protein in CPV-2a subtype is still exist in our country.