猪圆环病毒2型山西分离株的遗传变异多样性分析  

Analysis of genetic variation diversity of porcine circovirus-2 virus genome isolated from Shanxi area

作　　者：吴忻[1] 孟帆[1] 姚敬明[1] 樊振华[1] 王娟萍[1] 韩一超[1] 米瑞娟[1] 薛翼鹏[1] 赵岳[1] 刘文俊[1] 

机构地区：[1]山西省农业科学院畜牧兽医研究所,山西太原030032

出　　处：《中国兽医学报》2017年第8期1442-1450,共9页Chinese Journal of Veterinary Science

基　　金：山西省科技攻关资助项目(20130311026-4)

摘　　要：为了进一步研究山西猪圆环病毒2型(PCV2)的遗传变异多样性情况,对山西2013—2016年间分离的9株猪圆环病毒流行株(SXQX、SXCZ、SXJC、SXJX、SXLL、SXPY、SXPG、SXXY、SXTY2株)的全基因组进行了扩增、克隆和测序,已收录入GenBank中。并将其全基因序列、ORF2序列和推导出的Cap蛋白氨基酸序列与不同国家和地区的28株主要流行株进行了遗传变异多样性分析,结果显示:9株PCV2山西流行株全基因组核酸序列全长SXJX、SXXY、SXJC株为1 768bp,其余均为1 767bp,分别约占33%和67%。9株PCV2流行株之间核苷酸同源性为94.7%~99.8%,与国内外28株参考株同源性为93.9%~99.9%,与国产疫苗株同源性(LG、DBN-SXO7-2、SH株)为95.1%~99.8%;PCV2全基因组序列的进化分析表明:本试验分离的SXJX、SXJC、SXXY株属于PCV2a亚型的2D亚群,SXLL、SXPY、SXCZ株属于PCV2b亚型的1C亚群,SXTY14、SXQX、SXPG株属于PCV2b亚型的1A/1B亚群,可见近几年,山西PCV2流行株以PCV-2b亚型为主。分离的9株PCV2的ORF2之间核苷酸和Cap蛋白氨基酸同源性分别为90.0%~100.0%和87.1%~100.0%,与28株参考株之间核苷酸和氨基酸同源性分别为87.6%~100.0%和84.1%~100.0%,与国产疫苗株核苷酸同源性和氨基酸同源性分别为91.0%~100.0%和89.3%~100.0%,同源性都较高。9株分离株中,有6株分离株(SXQX、SXTY14、SXPG、SXXY、SXJC、SXJX)Cap蛋白氨基酸为233个,其中SXQX、SXTY14、SXPG株的ORF2位于1 033~1 734bp,SXXY、SXJC、SXJX株的ORF2位于1 034~1 735bp,3株分离株(SXCZ、SXLL、SXPY)Cap蛋白氨基酸为234个,其ORF2位于1 030~1 734bp,而与其他基因组序列为1 767bp分离株的ORF2相比,1 030~1 734bp位置多了3个碱基TCA,导致其氨基酸序列在234位置增加1个K(Lys)。另外还发现9株PCV2Cap蛋白除了唯一糖基化位点(NYS)(第143~145位氨基酸)呈高度保守外,还存在较多的氨基酸变异,这为山西地区PCV2的免疫预防等的研究提供理论依据,并为深入开展PCV2的分子致病机�In order to study genetic variation diversity of porcine circovirus type 2 （PCV2） strains in Shanxi, the genomic sequences of nine PCV2 strains including SXQX, SXCZ, SXTY2, SXJC, SXJX, SXLL,SXPY,SXPG and SXXY recently isolated from some areas of Shanxi from 2013 to 2016, was cloned,sequenced and received by GenBank. The amplified PCV2 genomic sequences, ORF2 sequences and Cap protein amino acid of these nine strains were analysed and compared with those of published 28 PCV2 strains by DNAStar, drawing phylogenetic tree. The results showed that the genomic sequences of SXJX,SXJC and SXXY PCV2 strains were 1 768 bp,and the others were 1 767 bp,which accounted for 33% and 67%, respectively. The homologies of nucleotide se- quences of the nine strains were 94.7%-99.8%, the homologies of nucleotide sequences of the nine strains with the 28 isolates from different regions of the world PCV strain were 93.9%-99.9%, and the homologies of nucleotide sequences of the nine strains with the domestic vaccine strains were 95.1%-99.8%. The phylogenetic analysed that SXJX, SXJC and SXXY belonged to genotype PCV-2D,SXLL,SXPY and SXCZ belonged to genotype PCV-1C, and SXTY14, SXPG and SXQX belonged to genotype PCV-1A/IB. Thus it proved that the epidemic strain of PCV2 was mainly PCV-2b in Shanxi. The homologies of ORF2 nucleotide sequences and Cap amino acid of the nine strains were 90.0%-100.0% and 87.1%-100.0% respectively,the homologies of ORF2 nucleotide sequences and Cap amino acid of the nine strains with the 28 isolates from different regions of the world PCV strain were 87.6%-100.0% and 84. 1%-100.0% respectively, and the homologies of ORF2 nucleotide sequences and Cap amino acid of the nine strains with the domestic vaccine strains were 91.0% -100.0% and 89.3%-100.0% respectively. The Cap amino acids of SXQX, SXJX,SXTY14,SXPG, SXJC and SXXY PCV2 were 233, ORF2 of SXQX, SXTY14 and SXPG located at 1 033-1 734 bp,ORF2 of SXXY,SXJX and SXJC located at 1 033--1 734 bp,and the Cap a- mino acids of SXCZ,SXLL and SXPY PCV2 were

关 键 词：猪圆环病毒2型 全基因组 遗传变异 多样性分析 

分 类 号：S852.65[农业科学—基础兽医学]