牙鲆蛋白质感染因子蛋白基因的克隆和结构分析

Cloning and characterization of prionprotein coding gene of bastard halibut(Paralichthys olivaceus)

采用RT-PCR方法分离牙鲆(Paralichthys olivaceus)蛋白质感染因子蛋白编码基因序列。推测的牙鲆蛋白质感染因子蛋白由472个氨基酸组成,分子量约49.6 kD,具有信号肽、短肽顺接重复、疏水区、糖基化位点、二硫键、糖基缩醛磷肌醇锚定位点等蛋白质感染因子蛋白特征结构域,与红鳍东方(Fugu rubripes)和大西洋鲑(Atlantic salmon)蛋白质感染因子蛋白的相似性分别为71.9%和66.4%。牙鲆蛋白质感染因子蛋白编码基因序列的获得为蛋白质感染因子进化与功能研究以及可能存在的鱼类传染性海绵样脑病研究奠定了基础。

Complementary DNA （eDNA） sequence of bastard halibut （Paralichthys olivaceus ）prion protein （PrP） encoding gene was cloned and characterized through RT-PCR approach. The PrP of bastard halibut consists of 472 amino acid residues, weighing about 49.6 kD. The deduced amino acid sequence is 71.9% similar to that of Japanese pufferfish （Fugu rubripes） and 66.4% similar to that of Atlantic salmon （Salmo salar）, and bears the structural signatures of PrPs including a signal sequence, tandem repeats, a hydrophobic region, two glycosylation sites, a disulphide bridge and a glycosyl phosphatidylinositol anchor site. The isolation of the PrP encoding gene will support the exploration concerning the evolutionary structure and function of PrPs and the possibility of the transmissible spongiform encephalopathies（TSE） existing in fishes.