武威驴PrP基因序列与结构特征的分析

Sequence analysis and structural features exploration of Wuwei asinine prion protein gene

以武威驴朊蛋白(PrP)基因序列与结构特征分析为基础,通过比对找到奇蹄动物与偶蹄动物之间PrP基因的差异,探究朊病毒病在奇蹄动物与偶蹄动物之间传播的种间屏障及其形成机制。分别从8头武威驴全血中提取基因组总DNA,用设计的特异性引物以聚合酶链反应扩增出细胞型朊蛋白基因(PrPC),并将其克隆到pGEM-T Easy载体。测序之后使用生物信息学方法与软件进行相关分析。序列测定分析表明,所克隆的武威驴PrP基因片段的大小为768bp,包含了驴PrP基因的完整编码区序列,为包含在单一外显子内的完整开放阅读框。本次克隆的武威驴PrP基因含5个短而富含G-C的元件,可编码九肽/八肽PQGGGGWGQ/PHGGGWGQ重复子。8个驴PrP基因之间核苷酸序列和推导的氨基酸序列的同源性分别介于99.2%~99.8%和98.4%~100%之间。武威驴与西吉驴、马之间PrP基因序列的同源性分别为99.2%和98.7%,与牛、绵羊、马之间PrP基因C端约100个残基区域的三级结构的相似性分别为91.84%、92.04%和97.35%。结果表明,奇蹄动物与偶蹄动物之间PrP基因存在明显的差异与进化分歧。

Based on sequence and structural features analysis of Wuwei asinine prion protein(PrP)gene,the objective of the study is to find the genetic difference of PrP between perissodactyla and artiodactyla animals and explore the formation mechanism of the species barrier of prion disease spread between perissodactyla and artiodactyla animals.The genomic DNA was extracted from whole blood of 8Wuwei asinine,respectively.By using the designed primers,the cell type prion protein(PrPC)gene was amplified by polymerase chain reaction,and cloned to pGEM-T Easy vector.The following bioinformatics methods and softwares were used to do the correlation analysis.In result,the cloned Wuwei asinine PrP gene is 768 bp in size,including a complete coding sequence of asinine PrP gene.The complete open reading frame of PrP gene only contains single exon.This clone of Wuwei asinine PrP gene contains five short G-C rich elements,encoding nonapeptide/octapeptide PQGGGGWGQ/PHGGGWGQ repeats.The homology of nucleotide sequence of PrP gene among 8donkey is from 99.2%to 99.8%,and the homology of the amino acid sequence is from 98.4%to 99.8%.The sequence homology of PrP gene between Wuwei donkey and Xiji donkey and horse is 99.2%and 98.7%,respectively,and the tertiary structural similarity of C-end area about 100 residues is 91.84%,92.04% and 97.35%,respectively.In conclusion,there is obvious difference and evolutionary divergence of PrP gene between perissodactyla and artiodactyla animals.