2004年SARS-CoV毒株S基因分子进化特征  

Evolutionary characteristics on S genes of SARS-CoVs in 2004

作　　者：黄平[1] 宋怀东[2] 邹丽容[1] 李晖[1] 俞守义[3] 

机构地区：[1]广东省疾病预防控制中心,广州510300 [2]上海第二医科大学附属瑞金医院医学基因组学国家重点实验室,上海200025 [3]南方医科大学流行病学教研室,广州510515

出　　处：《中国人兽共患病学报》2006年第10期957-960,共4页Chinese Journal of Zoonoses

基　　金：国家自然科学研究基金资助(No.30340014);广东省重点科技项目(No.2003B60127)

摘　　要：目的通过对2004年SARS-CoV毒株S基因序列的变异分析,揭示SARS-CoV毒株S基因进化与SARS流行的关系。方法对广东地区2004年2株SARS-CoV毒株S基因进行序列分析,其余15株毒株S基因序列从GenBank检索,采用DNAStar5.0软件,对检索的SARS-CoV的S基因核苷酸序列进行比对和分析;并结合临床资料对变异毒株进行进化速度分析。结果17株毒株中,S基因7个氨基酸位点全部置换,35个氨基酸位点在不同毒株中置换;所有SARS-CoV均通过氨基酸227位点的置换,增加一个糖基化位点。同义进化中,S基因置换速度为1.46×10-6个核苷酸,进化线性回归方程为Y=1.46×10-6X+0.000736,同时通过Ka计算显示S基因进化明显存在选择性压力。2004年17株SARS-CoV毒株可以分为两条进化途径,其中广东地区的人类的GZ0401毒株与果子狸的PC4-115毒株核苷酸同源性达到99.97%,氨基酸同源性为100%。结论冠状病毒S基因的1个糖蛋白位点增加,可能导致人类SARS-CoV毒株出现并SARS流行;2004年果子狸冠状病毒与人类SARS-CoV毒株分子结构类似,可能存在交叉宿主。S基因同义进化速度较流感HA1基因慢4.2倍,但基因进化明显存在选择性压力。To reveal the relation between evolution of S genes in SARS-CoVs and epidemic of SARS by means of analyzing the genetic variation of SARS-CoVs in 2004,the S genes of SARS-CoVs （2 in human, 10 in HPC） sequenced from Guangdong province were detected and others were collected from GenBank, which were analyzed with DNAstar5.0, and compared with the differences among S genes. The molecular evolution in speed was carried out by way of analyzing the clinical data. There were amino acid substitutions in S gene of all 17 strains in 2004, with 35 amino acid substitutions in different strains, and there was one more glycoprotein domain in No 227 amino acid in entire human SARS-CoVs. In the synonymous variation, the evolutionary rate in S gene was 1.46 × 10^-8 and the evolutionay linear regression equation was Y= 1.46 × 10^-8 X＋ 0. 000736. The evolution on s gene remarkably resulted from the selective pressure as showing in Ka value. Seventeen strains in 2004 were evo- lutionally divided into two ways,in which the homology between human GZ0401 and HPC PC4-115 was 99.97% in nucleotide sequence and 100% in amino acid sequence. Increase of one glycoprotein domain in S gene in SARS-CoV might possibly result in emergence and outbreak of SARS. There exists cross-host in human and HPC between the human SARS-CoV and HPC coronavirus. S gene in the synonymous variation is 4.2 times slower than HA1 gene of in fluenza but the selective pressure on S gene significantly exists in biological evolution.

关 键 词：严重急性呼吸综合征 SARS-冠状病毒 S基因 进化 

分 类 号：R373[医药卫生—病原生物学]