来自肺炎患儿的A1基因亚型人偏肺病毒全基因组序列分析  

Whole Genome Sequencing and Phylogenetic Analyses of Sub-genotype A1 of the Human Metapneumovirus Detected in an Infant with Pneumonia

作　　者：郭春颖[1] 朱汝南[1] 孙宇[1] 赵林清[1] 邓洁[1] 王芳[1] 宋秦伟[1] 田润[1] 钱渊[1] 

机构地区：[1]首都儿科研究所病毒研究室,儿童病毒病病原学北京市重点实验室,北京100020

出　　处：《病毒学报》2016年第6期758-767,共10页Chinese Journal of Virology

基　　金：北京市卫生系统高层次卫生技术人才培养计划(项目号:2013-3-087);北京市科技计划(项目号:Z111107056811041),题目:北京儿童急性传染病监测体系的建立;国家自然科学基金(项目号:30872153),题目:新发现的病毒与儿科呼吸道感染的病原学研究

摘　　要：人偏肺病毒（human metapneumovirus,HMPV）是婴幼儿呼吸道感染的重要病原之一。本研究目的在于分析在HMPV监测中发现的少见型别A1基因亚型BJ-1610的全基因组序列,为HMPV的进一步研究提供数据支持。BJ-1610来源于一名患有肺炎的3月龄女婴的鼻咽洗液标本。对该毒株进行全基因组RNA分段扩增、测序、序列拼接并分析其基因组特征、变异程度及是否存在重组等现象。BJ-1610株基因组全长为13 406nt（KU821121）。BJ-1610与HMPV参考株进行全基因和各蛋白核苷酸和氨基酸序列比较,显示全基因组的核苷酸相似性范围为81.2%-98.4%,其中相似性最高的为澳大利亚株（KC562226）,而SH和G基因则与其他澳大利亚株相似性更高。系统进化分析发现BJ-1610与HMPV A1基因亚型参考株位于同一分支,显示了与相似性分析相同的特征。对BJ-1610的膜表面蛋白F、SH和G蛋白序列进行分析结果显示,F蛋白最为保守,SH基因编码区的终止密码发生了突变,导致终止密码后移15位,长度由552bp变为567bp;G蛋白氨基酸序列突变较多,并导致N-糖基化位点的减少。HMPV作为儿童呼吸道疾病的重要病原之一,对其流行株基因组的分析将对其流行特征、遗传进化、致病机理、疫苗研制和抗病毒药物研发等方面的研究产生积极的推动作用。The human metapneumovirus（HMPV）is an important pathogen in respiratory-tract infections in children.We undertook genomic sequence analyses and described the genetic characteristics of an uncommon sub-genotype,the HMPV A1 strain,and provide useful data for further studies.The HMPV A1（BJ-1610）strain was identified from a nasopharyngeal aspirate collected from a 3-month-old female with bronchopneumonia.Gene fragments of BJ-1610 were amplified by reverse transcription-polymerase chain reaction（RT-PCR）and assembled by DNAStar software.Sequence alignment for BJ-1610 and other HMPV reference strains with four known genotypes available in the GenBank database was conducted by DNAStar.Phylogenetic trees were created using MEGA 6.06 software.The whole genome of BJ-1610 was 13406nt in length（GenBank accession number：KU821121）.Compared with HMPV reference strains,BJ-1610 shared the highest similarities with HMPV/AUS/150229278/2003/A（KC562226）from Australia,which was classified into sub-genotype A1.The nucleotide identity of the full genome between BJ-1610 and KC562226was 98.4%.N,P,F,M2-2and L genes had great similarity with KC562226 compared with other reference strains,whereas SH and G genes shared higher similarities with other strains of sub-genotype A1.Phylogenetic analyses of the whole genome showed that BJ-1610 was clustered into sub-genotype A1 and was close to KC562226.The N,P,M,F,M2-1,M2-2and L genes of BJ-1610 showed the same genetic features as the whole genome,whereas the variable genes SH and G were closest to KC403980.The F protein of BJ-1610 showed high genetic conservation.The length of the SH protein of BJ-1610 changed from 552 bp to 567 bp due to mutations in the stop codon.The amino-acid mutations on protein G led to a decrease in the number of N-glycosylation sites.As an infrequently circulating genotype,sequence analyses of the whole genome of a HMPV A1strain（BJ-1610）will promote further studies on its epidemiology and pathogenicity,and aid the development of vaccines and antivi

关 键 词：儿童肺炎 人偏肺病毒 A1基因亚型 基因组 序列分析 

分 类 号：R373.1[医药卫生—病原生物学]