Intermolecular crosslinking of abnormal prion protein is efficiently induced by a primuline-sensitized photoreaction
Intermolecular crosslinking of abnormal prion protein is efficiently induced by a primuline-sensitized photoreaction
复制标题
报春花碱敏化光反应有效诱导异常朊病毒蛋白的分子间交联
DOI：
10.1016/j.bbagen.2018.11.008
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Doh-ura Katsumi
中科院分区：
文献类型：
--
作者：
Teruya Kenta;Nishizawa Keiko;Oguma Ayumi;Sakasegawa Yuji;Kitamoto Tetsuyuki;Doh-ura Katsumi
在朊病毒疾病中，由异常朊病毒蛋白（PrPSc）组成的感染性致病颗粒在大脑中积聚。PrPScis的生物化学特征是其蛋白酶抗性核心（PrPres），但其结构特征尚未完全阐明。在这里，我们报告说，樱草碱，具有光敏活性的荧光染料，显着增强紫外线照射诱导的抗SDS的PrPSc/resoligomer的形成，可以检测到朊病毒感染的材料的免疫印迹分析。这种寡聚体的形成特异性地发生在PrPSc/ress中，但不发生在正常的朊病毒蛋白中，并且使用纯化的PrPSc/ress以及未纯化的材料证明了这一点。低聚物的形成进行樱草碱剂量和紫外线照射时间依赖性的方式。用脲或甲酸处理不使低聚物断裂成单体。芳香族氨基酸的存在也没有改变低聚物的形成。一组抗朊病毒蛋白抗体的分析表明，针对PrPresN-末端区域的抗体在二聚体中的反应性低于单体。这些研究结果表明，樱草碱敏化的光反应增强了PrPSc/resmolecules在PrPres的N-末端区域的疏水区域的分子间交联。在其他化合物的筛选中，光反应性化合物如野樱草苷表现出类似但比樱草碱低的低聚物形成活性。这些化合物的增强光反应将有助于评价PrPSc/res的结构特征，特别是PrPSc/res分子之间的相互作用。
In prion diseases, infectious pathogenic particles that are composed of abnormal prion proteins (PrPSc) accumulate in the brain. PrPScis biochemically characterized by its protease-resistance core (PrPres), but its structural features have not been fully elucidated. Here, we report that primuline, a fluorescent dye with photosensitization activity, dramatically enhances UV-irradiation-induced SDS-resistant PrPSc/resoligomer formation that can be detected by immunoblot analysis of prion-infected materials. This oligomer formation occurs specifically with PrPSc/resbut not with normal prion protein, and it was demonstrated using purified PrPSc/resas well as unpurified materials. The oligomer formation proceeded in both primuline-dose- and UV irradiation time-dependent manners. Treatment with urea or formic acid did not break oligomers into monomers. Neither did the presence of aromatic amino acids modify oligomer formation. Analysis with a panel of anti-prion protein antibodies showed that the antibodies against the N-terminal region of PrPreswere less reactive in the dimer than the monomer. These findings suggest that the primuline-sensitized photoreaction enhances intermolecular crosslinking of PrPSc/resmolecules at a hydrophobic area of the N-terminal region of PrPres. In the screening of other compounds, photoreactive compounds such as luciferin exhibited a similar but lower activity with respect to oligomer formation than primuline. The enhanced photoreaction with these compounds will be useful for evaluating the structural features of PrPSc/res, especially the interactions between PrPSc/resmolecules.