ANIMALS

在这个由四个科学项目和四个核心组成的申请中，我们建议继续我们的研究 专注于由人类朊病毒疾病引起的神经变性，其中最常见的是散发性的 克雅氏病朊病毒似乎只由PrPSc分子组成，PrPSc分子是由PrPc前体通过一个 不太了解的过程。本文所述的研究旨在定义PrPSc的结构， 表征小分子与PrPc和PrPSc的相互作用，并剖析分子 控制不同人类朊病毒株繁殖的事件。在项目1中，我们建议研究 聚氧乙烯酸盐（POM）与PrP、Sc. POM磷钨酸盐阴离子[PW 12 O 40]（PTA） 特异性结合PrPSc，但不结合PrP。POM是一类具有刚性的无机金属氧化物簇合物， 多面体结构，在尺寸、形状和电荷密度上显示出实质性的变化。在项目2中，我们 建议对55个残基的MoPrP（89-143，P101 L）肽进行纤维衍射研究， 遗传性朊病毒病，一种已知形成淀粉样纤维的20聚体wt PrP（106-126）肽， 截短的（PrP 27-30）和全长PrPSc，这两者在野生型动物中都是感染性的。在项目3中，我们 研究引起克雅氏病的朊病毒这些研究是可能的，因为我们最敏感的Tg小鼠 表达嵌合人/鼠PrP的细胞系在接种sCJD后约80天内死亡 朊病毒在这些Tg小鼠中对人朊病毒的相对快速的生物测定使得测量人朊病毒的滴度成为可行的。 朊病毒在整个大脑以及周围器官和体液收集从死亡的sCJD患者。 我们还建议建立sCJD和变异型（v）CJD的豚鼠模型。在项目4中，我们建议 发现结合并稳定人PrPc的新配体。我们还计划确定这种配体是否 抑制HuPrPc转化为HuPrPSc。使用虚拟筛选方法， 分子将对接到HuPrPc的已知结构上。高分化合物将被测试， 生物活性结合，控制抗淀粉样蛋白抑制剂倾向的非特异性抑制。的 所有拟议研究的最终目标是确定形成的分子事件， 人类朊病毒，以便开发治疗人类朊病毒疾病的疗法。

In this application comprising four scientific projects and four-cores, we propose to continue our studies focused on neurodegeneration caused by human prion diseases, the most common of which is sporadic (s) CJD. Prions seem to be composed solely of PrPSc molecules, which are derived from a precursor PrPc by a poorly understood process. The studies described here are aimed at defining the structure of PrPSc, characterizing the interactions of small molecules with both PrPc and PrPSc and dissecting the molecular events governing the propagation of different human prion strains. In Project 1, we propose to study the interactions of polyoxometalates (POMs) with PrP,S c . The POM phosphotungstate anion [PW12O40] (PTA) binds specifically to PrPSc, but not to PrP . POMs are a large class of inorganic metal oxide clusters with rigid polyhedral structures displaying substantial variations in size, shape, and charge density. In Project 2, we propose to carry out fiber diffraction studies of the 55-residue MoPrP(89-143,P101L) peptide that causes inherited prion disease, a 20 mer wt PrP(106-126) peptide known to form amyloid fibrils as well as purified truncated (PrP 27-30) and full-length PrPSc, both of which are infectious in wild-type animals. In Project 3, we propose to study the prions causing sCJD. These studies are possible because our most sensitive Tg mouse line expressing chimeric human/mouse PrP succumbs to disease in ~80 days after inoculation with sCJD prions. Relatively rapid bioassays of human prions in these Tg mice make it practical to measure the titers of prions throughout brain as well as in peripheral organs and body fluids collected from dead sCJD patients. We also propose to develop guinea pig models of sCJD and variant (v) CJD. In Project 4, we propose to discover new ligands that bind to and stabilize human PrPc. We also plan to determine whether such ligands inhibit the conversion of HuPrPc into HuPrPSc. Using a virtual screening approach, large libraries of organic molecules will be docked against the known structure of HuPrPc. High-scoring compounds will be tested for binding biophysically, controlling for non-specific inhibition to which anti-amyloid inhibitors are prone. The ultimate goal of all the proposed studies is to define the molecular events that feature in the formation of human prions in order to develop therapeutics that cure the human prion diseases.