摘要
目前,国际上已分离获得2个不同血清型的猪圆环病毒(PCV),并命名为猪圆环病毒1型(PCV-1)和猪圆环病毒2型(PCV-2)。PCV-1对猪无致病性,而PCV-2被认为是引起断奶仔猪多系统衰竭综合征(PMWS)的主要病原。PCV基因组为单股环状双向DNA,由2个头-头相对排列的开放性阅读框和基因间隔区组成,包含rep基因、cap基因及病毒DNA复制起始区茎环序列。rep基因编码2种不同的复制酶相关蛋白,cap基因编码病毒结构蛋白或衣壳蛋白,茎环序列在病毒蛋白合成、DNA自身复制及子代病毒产生中发挥重要作用。PCV-2衣壳蛋白110位(P→A)和191位(R→S)氨基酸突变,提高PCV-2在体外组织培养中的增殖效率,而减弱其对动物的致病性和毒力。
Two genotypes of Porcine circovirus （PCV） have been isolated worldwide and are referred as Porcine circovirus type 1 （PCV-1） and Porcine circovirus type 2 （PCV-2）. PCV-1 is nonpathogenic for pigs, whereas Porcine circovirus type 2 （PCV-2） is considered as the major causative agent of Postweaning multisystemic wasting syndrome （PMWS） in domestic pigs. The genome of Porcine circovirus is an ambisense, single-strand, circular DNA and constructed by two head-to-head arranged open reading frames and an intergenic region. It contains rep gene, cap gene, and loop-sequence at the origin of viral DNA replication, the rep gene encoding two replicase proteins, the cap gene supplying the viral structural protein or capsid protein, and the loop-sequence playing an important role in viral protein synthesis, DNA self-replication and progeny virus production. The 110 aa（P→A）and 191 aa（R→S）mutations in the capsid of PCV- 2 enhanced the growth ability of PCV-2 in vitro and attenuated the virus in vivo.
出处
《动物医学进展》
CSCD
2006年第7期6-10,共5页
Progress In Veterinary Medicine
基金
农业部948项目(2004-Z41)
关键词
猪圆环病毒
基因组
结构
特征
Porcine circovirus
genome
structure
characterization
