猪嵴病毒VP1基因序列测定与分析

Sequenceing and analysis of VP1 gene of procine kobuvirus

【目的】对猪嵴病毒（PKV）VP1基因进行测序与同源性分析,确认其可能来源,为今后的生物学特性分析及仔猪腹泻防治工作提供科学依据。【方法】采用RT-PCR对GXPKV-1毒株VP1基因进行克隆,运用DNASTAR软件包中Megalign程序对测序获得的VP1基因进行核苷酸序列及其推导氨基酸序列同源性分析。【结果】GXPKV-1毒株VP1基因全长762 bp,共编码254个氨基酸,与Gen Bank已公布的13株参考毒株VP1基因的核苷酸同源性为74.1%～85.4%,推导氨基酸同源性为81.1%～93.3%。根据VP1基因推导氨基酸序列进行系统发育进化分析,发现GXPKV-1毒株与Gansu-2012、JS1419等国内参考毒株同属于同一亚群,而与瑞士分离株Swine-S-1-2007、泰国分离株THA-2008、美国分离株H_24-2012-USA及四川分离株CHN-SC-2011-02等的亲缘关系较远。【结论】猪嵴病毒GXPKV-1毒株起源于国内流行毒株的传播,在新的环境下虽然其VP1基因核苷酸发生变异,但由于同义翻译,推导氨基酸的同源性仍然较高,说明碱基突变并未引起蛋白结构的改变。

[Objective]The present experiment was conducted to analyze sequence and homology of VP1 gene of procine kobuvirus（PKV）, and ascertain its possible source, in order to provide scientific basis for biological characteris- tics analysis and prevention of piglet diarrhea in future. [Method]The VP1 gene was cloned from strain GXPKV-I using RT-PCR technique. The homology of its nucleotide sequence and the deduced amino acid sequence was analysed by using Megalign program in DNASTAR software packages. [ Result ]The results showed that, the GXPKV-! VP1 gene was 762 bp in length, encoding 254 amino acids. The VP1 gene of GXPKV-1 shared nucleotide homology of 74.1%-85.4% and amino acid homology of 81.1%-93.3% with those of 13 strains published in GenBank. The phylogenetic evolution analysis showed that, GXPKV-1 stain, Gansu-2012 and JS1419 belonged to same subgroup, and GXPKV-1 stain had distant ge- netic relationship with Swiss isolates Swine-S-I-2007, Thailand isolates THA-2008, United States isolates H24-2012- USA and Sichuan isolates CHN-SC-2011-02. [ Conclusion ]The GXPKV-I strain is originated in the spread of pandemic strain in China. Under the new environment, the nucleotides of PKV VP1 gene mutate, however most of which is synony- mous mutation, so the homology of amino acid are still high, it indicates that base variation doesn＇ t cause change of pro- tein structure.