IBV D41株主要结构基因及3′端非编码区序列分析

采用反转录及聚合酶链式反应 ( RT-PCR) ,成功地扩增出鸡传染性支气管炎病毒 ( IBV)人工致弱毒D41株 S1基因、M基因、N基因和基因组 3′端非编码区 ( U TR)的 c DNA。序列测定结果表明 :D41株的 S1基因全长 1611bp(从 ATG到 S前体蛋白裂解位点 ) ,编码一条由 53 7个氨基酸组成的多肽 ;M基因全长 678bp,编码一条由 2 2 6个氨基酸组成的多肽 ;N基因全长 12 3 0 bp,编码一条由 410个氨基酸残基组成的多肽 ,3′端 UTR长度为52 5bp,其中高变区 ( HVR)长度为 2 2 5bp。与国内外已报道的一些 IBV标准毒株的相应基因序列进行核苷酸序列同源性分析后发现 :D41株与麻省血清型的毒株同源性最高 ,尤其与国际常用的标准疫苗株 H52和 H12 0的亲缘关系最接近。但它与国内“腺胃型”毒株 QXIBV在系统发生进化树上却相隔较远

Sequence analysis of main structural genes and 3' end UTR of avian infectious bronchitis virus strain D41

In this paper, the cDNA of S1 gene, M gene, N gene and 3' end UTR of avian infectious bronchitis virus(IBV) strain D41, an attenuated vaccine strain, were amplified by RT PCR and full sequences were first reported. The sequence of S1 gene was consisted of 1 611 bp, from initiation codon ATG to the possible cleavage of spike glycoprotein. It predicted a polypeptide of 537 amino acids. The sequence of M gene was consisted of 678 bp. It predicted a polypeptide of 226 amino acids. The sequence of N gene was consisted of 1230 bp. It predicted a polypeptide of 410 amino acids. The sequence of 3' end UTR was consisted of 525 bp, including a 225 bp HVR. After comparing the above genes of D41 with some published IBV standerd strains, it was found that D41 had a close relationship with some strains that belong to the Massachusetts serotype, especially with H52 and H120 which are all common vaccine strains. But a phylogenetic tree based on requenees obtained showed that there was a long distance between D41 and QXIBV, a proventriculus type isolated in China.