Zhao Wenjun, Gao Mengying, Xu Qianqian, Xu Yang, Zhao Yan, Chen Yuqiu, Zhang Tingting, Wang Qiuling, Han Zongxi, Li Huixin, Chen Lingfeng, Liang Shuling, Shao Yuhao, Liu Shengwang
Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, People's Republic of China.
Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, People's Republic of China.
Vet Microbiol. 2017 Jan;198:9-16. doi: 10.1016/j.vetmic.2016.11.014. Epub 2016 Nov 17.
We investigated the genomic characteristics of 110 LX4 genotype strains of infectious bronchitis viruses (IBVs) isolated between 1995 and 2005 in China. The genome of these IBVs varies in size from 27596bp to 27790bp. Most IBV strains have the typical genomic organization of other gamacoronaviruses, however, two strains lacked 3a and 5b genes as a result of a nucleotide change within the start codon in the 3a or 5b genes. Analysis of our 110 viruses revealed that recombination events may be responsible for the emergence of the LX4 genotype with different topologies. Most of these viruses disappeared (before mid-2005) because they were not "fit" to adaptation in chickens. Finally, those of the "fit" viruses (after mid-2005) continued to evolve and have become widespread and predominant in commercial poultry. In addition, few of these viruses experienced recombination with those of the vaccine strains at the 3' end of the genome.
我们研究了1995年至2005年间在中国分离出的110株传染性支气管炎病毒（IBV）LX4基因型毒株的基因组特征。这些IBV的基因组大小在27596bp至27790bp之间变化。大多数IBV毒株具有其他γ冠状病毒典型的基因组结构，然而，由于3a或5b基因起始密码子内的核苷酸变化，有两个毒株缺少3a和5b基因。对我们的110株病毒的分析表明，重组事件可能是导致具有不同拓扑结构的LX4基因型出现的原因。这些病毒中的大多数（在2005年年中之前）消失了，因为它们不“适合”在鸡体内适应。最后，那些“适合”的病毒（在2005年年中之后）继续进化，并在商业家禽中广泛传播且占主导地位。此外，这些病毒中很少有在基因组3'端与疫苗毒株发生重组的情况。
