Pharmacological chaperone for the structured domain of human prion protein
Pharmacological chaperone for the structured domain of human prion protein
复制标题
DOI：
10.1073/pnas.1009062107
复制
发表时间：
2010-10-12
影响因子：
11.1
通讯作者：
Collinge, John
中科院分区：
文献类型：
--
作者：
Nicoll, Andrew J.;Trevitt, Clare R.;Collinge, John
在朊病毒疾病中，错误折叠的蛋白质聚集体来源于细胞朊病毒蛋白（PrPC）。已经报道了许多配体与人PrPC（huPrP）结合，但没有与具有药理学伴侣所需的亲和力的结构化区域结合。使用平衡透析，我们筛选了以前建议与PrP相互作用的分子，以区分那些不与PrP相互作用的分子，表现为非特异性聚离子聚集体或形成真正的相互作用。那些结合的蛋白质有可能作为药理学伴侣。在这里，我们报告的阳离子四吡咯[Fe（III）-TMPyP]，它显示出有效的抗朊病毒活性，结合到huPrP的结构化区域。使用电池的生物物理技术，我们证明，Fe（III）-TMPyP形成1：1复合物通过结构化的C末端的huPrP的Kd为4.5 +/- 2 μ M，这是在其范围内的IC 50治疗朊病毒感染的细胞1.6 +/- 0.4 μ M和浓度所需的抑制蛋白质错误折叠循环扩增。因此，该分子测试了huPrP（C）的稳定化作为原理可用于治疗人朊病毒疾病的假设。具有确定的3D结构的结合位点的识别开辟了设计稳定huPrP并防止其转化为疾病相关形式的小分子的可能性。
In prion diseases, the misfolded protein aggregates are derived from cellular prion protein (PrPC). Numerous ligands have been reported to bind to human PrPC (huPrP), but none to the structured region with the affinity required for a pharmacological chaperone. Using equilibrium dialysis, we screened molecules previously suggested to interact with PrP to discriminate between those which did not interact with PrP, behaved as nonspecific polyionic aggregates or formed a genuine interaction. Those that bind could potentially act as pharmacological chaperones. Here we report that a cationic tetrapyrrole [Fe(III)-TMPyP], which displays potent anti-prion activity, binds to the structured region of huPrP. Using a battery of biophysical techniques, we demonstrate that Fe(III)-TMPyP forms a 1: 1 complex via the structured C terminus of huPrP with a K-d of 4.5 +/- 2 mu M, which is in the range of its IC50 for curing prion-infected cells of 1.6 +/- 0.4 mu M and the concentration required to inhibit protein-misfolding cyclic amplification. Therefore, this molecule tests the hypothesis that stabilization of huPrP(C), as a principle, could be used in the treatment of human prion disease. The identification of a binding site with a defined 3D structure opens up the possibility of designing small molecules that stabilize huPrP and prevent its conversion into the disease-associated form.