大熊猫源犬瘟热病毒基因组遗传特征分析  

Genomic Characterization of the Newly Emerged Canine Distemper Virus in Giant Panda

作　　者：金艺鹏[1] 刘巧荣[2] 孙明[2] 乔雁超 乔明明[2] 刘伯华[2] 林德贵[1] 陈西钊[2] 

机构地区：[1]中国农业大学动物医学院,北京100193 [2]北京世纪元亨动物防疫技术有限公司,北京100094

出　　处：《中国农业科学》2015年第7期1445-1452,共8页Scientia Agricultura Sinica

摘　　要：【目的】对首次暴发的大熊猫源性犬瘟热病毒(panda derived-canine distemper virus,P-CDV)全基因组进行克隆测序,以了解大熊猫源CDV的全基因组遗传变异情况,进一步追踪感染源,为大熊猫犬瘟热防控提供理论依据。【方法】根据Gen Bank公布的CDV全基因组序列设计17对特异性引物,利用RT-PCR技术,从感染犬瘟热病毒的大熊猫肺渗出液中分片段扩增CDV全基因序列,并克隆到p MD19-T载体中;经测序、拼接,获得第一个P-CDV全长c DNA序列;利用DNAman生物学分析软件分别对全基因组序列、H蛋白基因序列、F蛋白基因序列、P蛋白基因序列、M蛋白基因序列等进行遗传变异分析,构建系统进化树。【结果】经序列测序和拼接,大熊猫源犬瘟热病毒全基因组长15 690 nt,Gen Bank登录号为KP677502,主要编码6种蛋白,分别是N蛋白、P蛋白、M蛋白、F蛋白、H蛋白和L蛋白,在各个基因及间隔区中未发现碱基插入和缺失。遗传进化分析显示,P-CDV全基因组与20株代表性CDV全基因组序列同源性为91.5%—98.7%,P-CDV与强毒株MKY-KM08(HM852904)、PS、HLJ1-06(JX681125)、Hebei(KC427278)以及AC96I-H358(AB753776)在一个大的分支上,与PS株(JN896331)亲缘关系最近,同源性为98.7%,与标准野毒株Strain A75-17(AF164967)同源性为95.7%,与疫苗株CDV3(EU726268)亲缘关系较远,同源性为91.5%。H蛋白氨基酸序列分析和系统进化树表明,大熊猫源犬瘟热病毒属于强毒株,基因型为Asia-I型。P-CDV各蛋白基因与20株代表性的毒株相比有9处氨基酸发生了变异,与Gen Bank上现有的CDV序列相比,其中3处是独有的,分别是:F蛋白基因的208位由N(Asn,天冬酰胺,强毒株多为N)或K(Lys,赖氨酸,弱毒株多为K)变成了S(Ser,丝氨酸),第215位由S变成了A(Ala,丙氨酸),P蛋白基因的58位由Q(Gln,谷氨酰胺)变成K(Lys,赖氨酸)。【结论】成功克隆了大熊猫源犬瘟热病毒的全基因,并完成了序列分析,发现了在F、P基因�[Objective] The objective of this study is to analyze the genetic variation of the newly emerged giant panda canine distemper virus by sequencing its full-length genome, thereby to track the source of infection and provide a theoretical basis for the prevention and control of giant panda CDV infection. [Method] According to the CDV genomic sequences published in GenBank, 17 pairs of oligonucleotide primers were designed, the overlapping fragments spanning whole genome of CDV were amplified by RT-PCR from lung exudate of the infected giant panda and then cloned into vector pMD19-T and sequenced, respectively, the determined sequences were spliced and assembled by using biological software DNAman. Based on above efforts, the first complete genome sequence of P-CDV isolated from giant panda was accomplished, and was further characterized by alignment with 20 published CDV whole-genome sequences from GenBank. Moreover, to track the source of infection, different phylogenetic trees were constructed according to complete genome as well as genes H, F, P and M, respectively.[Result]The genome of the giant panda CDV is 15 690 nucleotides in length （GenBank accession No. KP677502）, and mainly encodes six genes in the order of 3′-N-P-M-F-H-L-5′. No nucleotides insert and deletion were observed in encoding and intergenic regions compared to other CDV complete genome sequences. Phylogenetic analysis of the giant panda CDV genome showed 91.5%-98.7% nucleotide identity with 20 representative CDV isolates. Along with virulent strains MKY-KM08 （accession no. HM852904）, PS, HLJ1-06 （accession no. JX681125）, Hebei （accession no. KC427278） and AC96I-H358 （accession no. AB753776）, P-CDV belongs to one large homogeneous clade, and is phylogenetically most closely related to the isolate PS with 98.7% identity at nucleotide. It shares 95.7% nucleotide identity with wild strain A75-17, and exhibits the lowest nucleotide similarity with standard vaccine strain CDV3 （91.5%）. Sequence analysis based on H gene ind

关 键 词：犬瘟热病毒 大熊猫 全基因组测序 序列分析 

分 类 号：S852.65[农业科学—基础兽医学]