Recombinant scrapie-like prion protein of 106 amino acids is soluble
Recombinant scrapie-like prion protein of 106 amino acids is soluble
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DOI：
10.1073/pnas.93.26.15457
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发表时间：
1996-12-24
影响因子：
11.1
通讯作者：
Prusiner, SB
中科院分区：
文献类型：
--
作者：
Muramoto, T;Scott, M;Prusiner, SB
朊蛋白痒病亚型（PrPSc）的N端可以被截断而不会失去痒病传染性，相应地，PrPC细胞亚型的N端被截断仍然允许转化为PrPSc。为了评估PrP分子的其他片段是否可以被删除，我们之前删除了PrPC中假定的二级结构区域；在本研究中，我们发现四个预测螺旋中的每一个的缺失都阻止了PrPSc的形成，停止转移效应区和C178A突变的缺失也阻止了PrPSc的形成。去除螺旋2和3之间的36个残基环并没有阻止蛋白酶抗性PrP的形成；在细胞裂解物中加入洗涤剂sarksyl可溶解PrP(Sc)106，使其保持对蛋白酶K消化的抗性。这些结果表明，PrP中所有二级结构的区域都是PrPSc形成所必需的，二硫键稳定螺旋3和4也是如此。PrP(Sc)106的发现将有助于PrPSc的结构研究、PrPSc形成机制的研究以及PrPSc特异性抗体的产生。
The N terminus of the scrapie isoform of prion protein (PrPSc) can be truncated without loss of scrapie infectivity and, correspondingly, the truncation of the N terminus of the cellular isoform, PrPC, still permits conversion into PrPSc, To assess whether additional segments of the PrP molecule can be deleted, we previously removed regions of putative secondary structure in PrPC; in the present study we found that deletion of each of the four predicted helices prevented PrPSc formation, as did deletion of the stop transfer effector region and the C178A mutation, Removal of a 36-residue loop between helices 2 and 3 did not prevent formation of protease-resistant PrP; the resulting scrapie-like protein, designated PrP(Sc)106, contained 106 residues after cleavage of an N-terminal signal peptide and a C-terminal sequence for glycolipid anchor addition, Addition of the detergent Sarkosyl to cell lysates solubilized PrP(Sc)106, which retained resistance to digestion by proteinase K, These results suggest that all the regions of proposed secondary structure in PrP are required for PrPSc formation, as is the disulfide bond stabilizing helices 3 and 4, The discovery of PrP(Sc)106 should facilitate structural studies of PrPSc, investigations of the mechanism of PrPSc formation, and the production of PrPSc-specific antibodies.