风疹病毒JR23株包膜糖蛋白E2的遗传与变异分析

Heredity and Variance Analyses of Envelope Glycoprotein E2 of Rubella Virus JR23 Strain

为了探讨风疹病毒(rubellavirus,RV)包膜糖蛋白E2的基因与蛋白的遗传与变异特点,利用DNAstar软件比较JR23株与GenBank中各参考株E2的基因与多肽序列,分析不同RV株E2基因之间的同源性及E2蛋白功能关键区的氨基酸变异。结果表明,RVE2基因序列比较保守,但JR23株E2基因序列与其它9个分离株之间有明显差异,变异主要集中在484nt～554nt。同源性为90 3%～92 6%之间,与美国疫苗株RA27/3同源性最高,与美国疫苗株HPV77同源性最低,GenBank中的参考株间同源性较高,在96 3%～100 0%之间。E2多肽变异集中于161aa～185aa,但在E2功能关键区,如N端序列、N联糖基化位点、胞质区等则无明显变异。表明RVE2基因序列相对保守,虽然JR23株与GenBank中各参考株的E2基因序列有明显差异,但JR23株E2蛋白在功能关键区表现出遗传稳定性。此结果为阐明RV分子流行病学特征提供了理论依据,也为研究RV分子进化特征及病毒与宿主细胞的相互作用奠定了坚实基础。

To study the heredity and variance characteristics of envelope glycoprotein E2 gene and protein of RV JR23 strain,the sequences of E2 gene and polypeptide of JR23 strain were compared with those of other 9 RV isolates documented in GenBank.The homology of E2 gene sequences of different RV isolates and the amino acid variances of functional regions of JR23 E2 protein were analyzed by DNAstar software.The results showed that RV E2 gene sequence was relatively conserved.There were obvious differences between JR23 strain and the other 9 RV isolates.E2 gene of JR23 strain had the highest homology with that of RA27/3 strain of America with the value of 926%.The lowest homology with JR23 strain occurred in HPV77 strain of America with the value of 903%.The variance of E2 gene of JR23 strain concentrated on the sequence of nt484-nt554.The homology of other 9 isolates was between 963% and 1000%.The variance of E2 polypeptide of JR23 strain concentrated on the sequence of aa161aa185.E2 protein of JR23 strain showed hereditary stability on some important regions,such as Nterminal region,Nglycosylation sites,cytoplasmic domain,etc.It proved that the key functional regions of E2 protein were relatively stable,although there were obvious differences between E2 gene of RV JR23 and those of the other 9 isolates documented in the GenBank.This study offers theoretical foundations for the investigation of RV molecular epidemiology,and for study on RV molecular evolution and the interaction of RV with host cells.