猪圆环病毒1型贵州分离株全基因组的克隆与序列分析

摘要

为了解猪圆环病毒（PCV）在贵州的分子流行病学和遗传变异情况，同时为其深入研究提供参考，应用PCR方法对采自贵阳、都匀和遵义地区疑似断奶仔猪多系统衰竭综合征的病料进行 PCV1全基因组的扩增、克隆和测序分析。结果表明：扩增克隆的4株PCV1基因组全长均为1759 bp，4株PCV1间的核苷酸序列相似性在99．1％～99．7％，与国内外其他PCV1参考毒株的核苷酸序列相似性均在98．1％以上，与参考毒株PCV2的核苷酸序列相似性在77％左右；4株PCV1与国内其他PCV1毒株位于同一进化分支， PCV1国外毒株则位于另一进化分支。4株PCV1和参考毒株 PCV2的 ORF1、ORF2推导氨基酸序列相似性分别为86．2％～87．8％和64．0％～68．2％，4株PCV1与PCV2的ORF1在复制起始区和其他功能区高度保守，可为构建嵌合病毒PCV1-2提供骨架。%The amplification,cloning and sequence of PCV 1 complete genome of four weaned pigs from Guiyang,Duyun and Zunyi infected with multi-systemic wasting syndrome were analyzed by PCR to study molecular epidemiology and genetic variation of PCV in Guizhou and to provide a reference for its further research.Total genome length of four PCV1 strains is 1759bp and the similarity of nucleotide sequence between four PCV1 strains is 99.1%~99.7%.The similarity of nucleotide sequence is above 98.1% and 77% compared with PCV1 and PCV2 reference strains in GenBank respectively.Four PCV1 strains and other PCV1 strains in china belong to the same evolution branch but foreign PCV1 strains belong to the other evolution branch.The similarity of amino acid sequence of four PCV1 strains is 86.2%~87.8% and 64.0%~68.2% compared with amino acid sequence deduced from ORF1 and ORF2 of PCV2 respectively.The ORF1 of four PCV1 strains and PCV2 in the origin of replication and other functional domain is highly conserved,which can provide a framework for structure of mosaic virus.