新的成人腹泻轮状病毒J19株NSP4和NSP5基因克隆和序列分析

Qoning and sequence analysis of NSP4 and NSPS genes of a novel rotavirus strain J19

目的克隆新的成人腹泻轮状病毒J19株NSP4和NSP5基因,并分析其基因序列。方法利用一种改进的非依赖核酸序列的单引物扩增方法扩增J19株NSP4和NSP5基因,克隆到 pMD18-T载体中并进行测序。在此基础上,将J19株NSP4和NSP5的蛋白序列与其他轮状病毒蛋白序列进行比较分析和种系进化分析。结果J19株NSP4和NSP5基因为基因10和11,全长为739 bp 和649 bp,它们分别编码213个和176个氨基酸。与J19株NSP4和NSP5蛋白序列一致性较高的分别是B组成人腹泻轮状病毒Bang373株(20．3％)和B组猪轮状病毒db101株(29．5％)。对J19株的 NSP4和NSP5的遗传进化分析表明,J19株在进化树上的位置都靠近A、B和C组轮状病毒分支的根部,而且它比较偏向B组轮状病毒的分支。结论J19株的NSP4和NSP5与其他轮状病毒的相应蛋白序列存在显著差异。J19株NSP4和NSP5的蛋白序列比较和遗传进化分析表明新的成人腹泻轮状病毒与成人腹泻轮状病毒可能有共同起源;但是新的成人腹泻轮状病毒与成人腹泻轮状病毒存在显著差异。

Objective To clone and sequence NSP4 and NSP5 genes of a novel rotavirus strain J19 causing adult diarrhea. Methods NSP4 and NSP5 genes of J19 were amplified by an improved single primer sequence-independent amplification method, cloned into pMD18-T vector, and then sequenced. Amino acid sequence comparison and pbylogenetic analysis of NSP4 and NSP5 of J19 were made with the known proteins of other rotaviruses. Results Genomic segment 10, 11 of J19 encoding NSP4 and NSP5 were 739 bp and 649 bp in length, and the deduced proteins were 213 AA and 176 AA respectively. NSP4 and NSP5 of J19 showed moderately higher identities to group B adult diarrhea rotavirus strain Bang373 （20.3 % ） and group B bovine rotavirus strain db101（29.5%）respectively. Phylogenetic analysis of NSP4 and NSP5 of J19 showed that J19 was positioned close to the ancestral nodes of group A, B, and C lineages. Conclusion NSP4 and NSP5 of J19 differed significantly with those of any other known rotaviruses. Protein sequence analysis and pbylogenetic analysis of J19 showed that the novel rotavirus and the classic may originate from a common ancestral virus.