鸽圆环病毒福建株全基因组序列分析

运用PCR技术从福建省某地发病信鸽组织中获得鸽圆环病毒（Pigeon circovirus,PICV）福建株（简称fj1株）全基因组序列,并对鸽圆环病毒福建株基因组核苷酸组成、结构及其遗传进行分析。结果表明,所获fj1株全基因大小2037 nt,包含有2个主要的开放阅读框（open reading frame,ORF）：ORF-V1（41～994nt）编码复制相关结构蛋白（the replicated-associated protein,Rep）,ORF-C1（1987～1166nt）编码核衣壳蛋白（the putative capsid protein,Cap）;在V1和C1的5＇端之间存在一个与圆环病毒滚环复制有关的高度保守的环状发夹结构。fj1株与GenBank登录所有鸽圆环病毒核苷酸同源性在84.5%～93.8%之间,与中国浙江鸽圆环病毒分离株zj1和zj2核苷酸同源性分别为88.7%和88.9%。从遗传进化上看,中国3株鸽圆环病毒均处在Cap蛋白起始密码子＂ATG＂分支,但分居不同亚群。

GENOMIC SEQUENCE ANALYSIS OF A CIRCOVIRUS ISOLATED FROM PIGEON

A circovirus was isolated from pigeon in Fujian Province,and the complete genomic sequence of the virus was amplified and cloned by overlapping PCR.The results demonstrated that the virus genome is 2037nt in lenghth,containing two major open reading frames（ORFs）：one is ORF-V1（from position 41nt to 994nt） coding for the replicase-associated protein（Rep）,the other is ORF-C1（from position 1987nt to 1166nt） coding for the putative capsid protein（Cap）.The 5＇ intergenic region contains the potential stem-loop and highly conserved hairpin,at which rolling circle replication（RCA） of the virus DNA strand was postulated to begin.Pairwise comparisons showed that the genomic nucleotide sequence of the virus had 84.5%～93.8% identities with other 15 strains deposited in GenBank.A phylogentic tree was built by MEGA with bootstrap support for 1000 replicates.The results showed that all 3 pigeon circoviruses isolated in China were in the same phylogentic lineage which the Cap protein starting codon was ＂ATG＂,but in different subgroup.