Nie Lei, Zhang Qing-xia, Han Zong-xi, Shao Yu-hao, Rong Jun-gong, Liu Sheng-wang, Kong Xian-gang
Division of Avian Infectious Diseases, National Key Laboratory of Veterinary Biotechnology Harbin Veterinary Researoh Institute, CAAS, Harbin 150001, Heilongjiang, China.
Bing Du Xue Bao. 2007 Jul;23(4):298-304.
Membrane (M) protein genes of 20 infectious bronchitis virus (IBV) strains isolated in China between 1995 and 2004 were sequenced and analyzed. The M genes of twenty isolates were composed of 672 to 681 nucleotides, encoding polypeptides of 223 to 226 amino acid residues. Variations of the deduced amino acids of M gene mainly occurred at positions 2 to 17 and 221 to 233, comparing with that of the IBV strain LX4. There were deletions or insertions in the M gene of Chinese isolates at amino acid position 2 to 6, leading to the loss or gain of a glycosylation site. Phylogenetic tree based on amino acid sequences of M genes from 20 Chinese isolates and 34 reference strains showed that they were classified into five distinct clusters. Most of the Chinese IBV strains were included in clusters II and IV, forming distinct groups. The isolates in cluster II showed a close evolutionary relationship with Taiwan isolates. Furthermore, recombination especially the recombination between field isolates and vaccine strains had been observed while comparing the phylogeny of M genes with those of S1 and N genes.
对1995年至2004年间在中国分离的20株传染性支气管炎病毒（IBV）的膜（M）蛋白基因进行了测序和分析。20株分离株的M基因由672至681个核苷酸组成，编码223至226个氨基酸残基的多肽。与IBV毒株LX4相比，M基因推导氨基酸的变异主要发生在第2至17位和第221至233位。中国分离株的M基因在氨基酸位置2至6处存在缺失或插入，导致一个糖基化位点的丢失或获得。基于20株中国分离株和34株参考毒株的M基因氨基酸序列构建的系统发育树表明，它们被分为五个不同的簇。大多数中国IBV毒株被归入簇II和簇IV，形成不同的组。簇II中的分离株与台湾分离株显示出密切的进化关系。此外，在比较M基因与S1和N基因的系统发育时，观察到了重组现象，尤其是田间分离株与疫苗株之间的重组。
