猪轮状病毒L1株VP7基因克隆及序列分析

根据GenBank已发表的猪轮状病毒VP7基因保守序列，设计特异性引物扩增猪轮状病毒L1株VP 7全基因序列并进行序列测定及分析。结果显示， L1株猪轮状病毒VP 7基因全长为1062 bp，包含一个982 bp的开放阅读框，编码326个氨基酸，与G5型参考毒株核苷酸同源性和推导的氨基酸同源性分别为88．8％～93．7％和93．3％～94．2％，系统进化树分析结果亦显示L1株与G5型参考毒株处于同一个群，由此确定L1株为G5型。与我国近几年流行的G9型毒株NMTL进行抗原表位分析结果显示，两个毒株在 aa25～aa29、aa86～aa102、aa142～aa152、aa211～aa226、aa263～aa286等区域存在明显差异，可能对其免疫保护性存在一定的影响。

Cloning and Sequence analysis of VP7 gene of porcine rotavirus L1 strain

The VP 7 gene ofporcine rotavirus have been cloned and sequenced using a pair of primers designed according to the published cDNA sequence.The results demonstrated that the VP7 gene was 1062 nucleotides long and contains a long open reading frame,which codes for a VP7 protein of 326 amino acids.The VP7 gene shared from 88.8% to 93.7% nucleic acid identity and from 93.3% to 94.2% amino acid identity with PRV G5 genotype reference strains. Phylogenetic analysis revealed that the VP7 gene of L1 strain grouped very closely G5 genotype reference strains. So L1 strain was proved to belong to G5 genotype. Results from the analysis of antigenic index, L1 strain and G9 genotype NMTL strain had differences in amino acid 25 to 29,86 to 102,142 to 152,211 to 226, 263 to 286,which fields would play a important role of immunogenicity of PRV.