东北虎朊病毒基因的克隆与序列分析

Molecular cloning and the sequences analysis of the prion protein gene in Amur tiger

根据已报道的哺乳动物朊病毒基因序列设计引物,采用PCR方法扩增了25只东北虎的朊病毒基因,克隆、测序及序列分析表明,所得到的东北虎朊病毒基因片段为402bp,编码134个氨基酸的前体蛋白,核苷酸序列同源性为99.67%。共发现了4个核苷酸多态性(T423C,A501G,C511A,A610G),其中C511A和A610G的碱基突变导致K171Q和A204T氨基酸的变异。与已报道的猫、貂、绵羊、鼠和犬等哺乳动物的氨基酸序列比较,结果与猫(AF003087,97.3%)和绵羊(97.3%)的氨基酸同源性最高。

The prion protein （PRNP） genes of 25 Amur tigers were amplified by PCR using primers designed from mammalian PRNP. These PCR products contain 402 bp encoding 134 amino acids, and have a homology of 99.67 %. Four single nucleotide polymorphisms （T423C, A501G, C511A, A610G） were found, and the C51 IA and A610G nucleotide substitution resulted in 2 amino acid changes （Lysinel71Glutamine and Alanine204T hreoine）. Compared the tiger PRNP with those of Felis catus, mink, sheep, mouse and dog, the Amur tiger PRNP had the highest homology with Felis catus AF003087 （97.3 %） and sheep （97.3 %）.