FIBER DIFFRACTION FROM PRIONS, OTHER AMYLOIDS, AND FILAMENTOUS VIRUSES

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 淀粉样蛋白和丝状病毒是丝状生物组合，不适合通过结晶学或核磁共振进行结构分析，但非常适合于纤维衍射。当蛋白质改变构象形成不溶的细丝时，就会形成淀粉样纤维，这可能会导致严重的损害甚至死亡。淀粉样变性包括阿尔茨海默病、S病、帕金森病、S病，以及克雅氏病、疯牛病等多种病毒病。哺乳动物的Prion是由异常折叠的PrP蛋白形成的具有感染性的聚集体。淀粉样蛋白具有交叉贝塔结构，但结构细节尚不清楚。电子显微镜、固体核磁共振和其他方法的纤维衍射为阐明包括Pron在内的淀粉样蛋白的结构提供了最大的希望。需要结构研究来回答基本的蛋白质折叠问题，了解淀粉样蛋白的形成，并进行合理的药物设计。从具有感染性的重组蛋白中提取的人工合成的普恩病毒已经开启了新的可能性。Prion可用性的提高，样品制备方法的改进，以及高强度、高质量的同步辐射为获得淀粉样物衍射数据提供了前所未有的机会。丝状植物病毒对农业、生物技术和食品安全具有巨大的重要性，但人们对其分子结构知之甚少。我们从低温电子显微镜的同步辐射衍射数据中得到的结构是这些重要病原体的唯一已发表的结构测定。我们使用非常少量的材料在受控条件下制造干燥的纤维。纤维衍射数据将来自脑来源的哺乳动物普鲁恩，来自感染性重组PrP的普恩菌株，来自真菌普恩-S，来自阿尔茨海默？S淀粉样α/β和其他淀粉样蛋白，以及丝状植物病毒。这些数据将用于评估和改进淀粉样蛋白结构的竞争模型，并确定丝状病毒结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Amyloids and filamentous viruses are filamentous biological assemblies, not suited to structural analysis by crystallography or NMR, but well suited to fiber diffraction. Amyloid fibers are formed when proteins change conformation to form insoluble filaments that can cause severe damage and even death. Amyloidoses include Alzheimer?s and Parkinson?s diseases and a variety of prion diseases including Creutzfeldt-Jakob disease and BSE (?mad cow disease?). Mammalian prions are infectious aggregates formed by the aberrantly folded protein PrP. Amyloids share a cross-beta structure, but structural details are not known. Fiber diffraction with electron microscopy, solid state NMR, and other approaches offers the best hope for elucidating structures of amyloids including prions. Structural studies are needed to answer fundamental protein folding questions, to understand amyloid formation, and for rational drug design. Synthetic prions derived from infectious recombinant protein have opened up new possibilities. Improved prion availability, improved methods of specimen preparation, and intense, high quality synchrotron radiation offer unprecedented opportunities to obtain amyloid diffraction data. Filamentous plant viruses are of enormous importance to agriculture, biotechnology and food security, but little is known about their molecular structures. Our structures from synchrotron diffraction data with cryo-electron microscopy are the only published structure determinations for these important pathogens. We use very small quantities of material to make dried fibers under controlled conditions. Fiber diffraction data will be obtained from brain-derived mammalian prions, from prion strains derived from infectious recombinant PrP, from the fungal prion HET-s, from the Alzheimer?s amyloid alpha/beta and other amyloids, and from filamentous plant viruses. The data will be used to evaluate and improve competing models for amyloid structure, and to determine filamentous virus structures.