猪非典型瘟病毒GX01-2018株全基因组分子特征的分析

Genomic characteristics of atypical porcine pestivirus GX01-2018 strain from Guangxi Province

猪非典型瘟病毒(APPV)被证实是新生仔猪先天性震颤的致病因子。为了解广西APPV流行毒株的分子遗传特征,采用RT-PCR分段扩增APPV阳性病料,经克隆、测序、拼接,获得1株APPV的全基因序列,遂被命名为GX01-2018株。结果显示,GX01-2018株基因组全长11 565 bp,包括一个编码3 635个氨基酸的阅读框(ORF)。同源性分析显示,GX01-2018株与国内代表毒株广西GX-CH_2016株、江西JX-JM01-2018A01株、广东China/GD-SD/2016株、广东GD株核苷酸序列的同源性分别为98.2%、92.9%、83.4%、90.8%。GX01-2018株与国外代表毒株美国000515株、德国Bavaria_S5/9株、奥地利AUT-2016_C株、荷兰NL1株核苷酸序列的同源性分别为87.8%、90.7%、90.5%、90.7%。上述国内外代表毒株间Npro、Erns、E2基因核苷酸序列的同源性分别为79.1%～97.2%、83.0%～98.4%、83.1%～96.8%。基于APPV全基因组以及E2、Npro、Erns基因核苷酸序列绘制遗传进化树,获得相似的进化树图。来自广西的GX01-2018株与欧洲型毒株位于一个分支,而同样来自广西的GX04/2017株与美洲型毒株位于另一个分支。表明APPV流行毒株具有遗传多样性,来自同一地区的流行毒株出现较大的遗传变异。

Aty pical poreine pestivirus(APPV)was recently demons traced to be the causative agent of congenital tremor(CT)in newborn piglets.To investigate the genomic characteristics of APPV from Guangxi Province,APPV fragments were amplified from APPV positive sample,coloned,sequenced and ligated,and the full-length genomic sequence of an APPV isolate named as GX01-2018 strain was acquired.In resu lt,the complete genome of GX01-2018 st rain was 11 565 bp,which included an open reading frame(ORF)encoding a polyprotein with 3 635 amino acids.Homology analysis revealed that homology identity of complete nucleotide sequence of GX01-2018 strain with GX-CH2016 strain from Guangxi,JX-JMO1-2018 A01 strain from Jiangxi,China/GD-SD/2016 strain from Guangdong,GD strain from Guangdong was 98.2%,92.9%,83.4% and 90.8% respectively.GX01-2018 strain shared 87.8%,90.7%,90.5% and 90.7% homology ide ntity with 000515 strain from USA,Bavaria_S5/9 st rain from Germany,AUT-2016_C strain from Austria,NL1 strain from The Netherlands Respectively.The nucleotide sequence homology identity of EZ,N^pro,E^rns genes among the above-mentioned strains was 79.1%-97.2%,83.0%-98.4% and 83.1%-96.8%,respectively.Phylogenetic analysis showed that the phylogenetic trees based on complete genome and E2,Npro and Ems gene nucleotide seque nces resulted in similar topology.GX01-2018 st rain from Guangxi together with European st rains belonged to one group,while GX04/2017 strain also from Guangxi together with American strains belonged to another group.The above-mentioned results indicated that APPV isolates showed genetic diversity and there existed large genetic variation among different strains from the same region.