标题: 中国农大刘金华教授团队揭示H9N2亚型禽流感复制力增强的关键机制 [打印本页] 作者: aoxiao168 时间: 2017-7-29 14:53 标题: 中国农大刘金华教授团队揭示H9N2亚型禽流感复制力增强的关键机制 一起努力一起飞， 2017更精彩！
近日，Journal of Virology杂志在线发表了中国农大刘金华教授团队关于H9N2亚型禽流感病毒由于M基因重配使得其在鸡体内复制力增强的研究成果。具体表现为，H9N2的M基因内5个氨基酸位点的变异在促进病毒复制过程中起重要作用。原文题为“M gene reassortment in H9N2 influenza virus promotes early infection and replication: contribution to rising virus prevalence in chickens in China”。
Abstract: Segment reassortment and base mutagenesis of influenza A viruses are the primary routes to the rapid evolution of high fitness virus genotypes. We recently described a predominant G57 genotype of avian H9N2 viruses that caused country-wide outbreaks in chickens in China during 2010-2013 which led to the zoonotic emergence of H7N9 viruses. One of the key features of the G57 genotype is the substitution of the earlier BJ/94-like M gene with the G1-like M gene of quail origin. We report here on the functional significance of the G1-like M gene in H9N2 viruses in conferring increased infection severity and infectivity in primary chicken embryonic fibroblasts and chickens. H9N2 virus housing the G1-like M gene, in place of BJ/94-like M gene, showed early surge in viral mRNA and vRNA transcription that were associated with enhanced viral protein production, and with early elevated release of progeny virus comprising largely spherical rather than filamentous virions. Importantly, H9N2 virus with G1-like M gene conferred extrapulmonary virus spread in chickens. Five highly represented signature amino acid residues (37A, 95K, 224N and 242N in M1 protein, and 21G in M2 protein) encoded by the prevalent G1-like M gene were demonstrated as prime contributors to enhanced infectivity. Therefore, the genetic evolution of M gene in H9N2 virus increases reproductive virus fitness, indicating its contribution to rising virus prevalence in chickens in China.
通讯作者介绍：刘金华教授，博士，博士生导师，中国农业大学预防兽医学系主任，长江学者特聘教授。主要研究工作包括动物流感病毒遗传演化、致病机理和防控技术等。已经在Science、PNAS、Lancet、JVI等国际权威SCI杂志发表多篇研究成果。在禽流感HIN1，H9N2，H7N9 等的遗传演化和致病机理方面有重大突破。