猪流行性腹泻病毒(PEDV)辽宁株序列测定及分析

Sequence and phylogenetic analysis of porcine epidemic diarrhea virus(PEDV) in Liaoning strain

为弄清2014年沈阳某猪场腹泻原因,应用RT-PCR方法对采自该场样品进行猪流行性腹泻病毒(PEDV)S1基因扩增,并将产物纯化后测序、分析。结果得到长为2 376 bp的S1基因序列;本病毒与2013年美国暴发毒株以及我国2010年毒株核苷酸和氨基酸同源性较高,而与疫苗株同源性较低;同时存在氨基酸的插入、缺失及糖基化位点的改变;在进化树上,与2010-2011年在我国暴发的猪流行性腹泻病毒为与同一亚群,与2013年美国毒株也有较近的亲缘关系。表明分离到猪流行性腹泻病毒,此病毒已发生部分变异,需给予密切重视。

In order to investigate the causes of diarrhea in a swine farm in Shenyang,we used RT-PCR to amplify the S1 gene of porcine epidemic diarrhea virus（PEDV）in the samples. Following the sequencing of the purified RT-PCR products and sequence assembly,we found that the DNA sequence of 2 376 bp obtained from the sample was the full-length PEDV S1 gene.Sequence comparison with other PEDV strains revealed that this Liaoning PEDV strain shared high identity in both nucleotide and amino acid sequences with the American strain from the outbreak of PEDV in 2013 and Chinese PEDV strain in 2010,while it had relatively low identity with the vaccine strain. Amino acid insertions,deletions and glycosylation modifications were observed cloned PED SI gene.The phylogenetic tree analysis showed that Liaoning PEDV strain was located in the same subcluster with other Chinese PEDV strains found between 2010 and 2011,and was closely related to American strain.These results suggest that variation has occurred in PEDV and it is necessary to keep attention on it.