PROTEIN AGGREGATION AND AMYLOIDAL FIBRIL FORMATION IN NANOPOLYMERIC

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 最近的实验研究表明，各种退行性疾病与具有特定β-折叠构象的不溶性蛋白质聚集体在身体组织中的沉积有关。这些聚集体被称为淀粉样原纤维。已经提出淀粉样纤维的形成是 由中间解折叠物质的性质决定。此外，最近的实验研究表明，当蛋白质被限制在膜中时，淀粉样纤维的形成可能是有利的。然而，还没有足够的理论或实验考虑集中在阐明的影响范围 和/或膜在淀粉样纤维形成中所起的作用。这成为要解决的重要问题，因为聚合蛋白递送系统提供了发生蛋白质纤维化的合适环境。我们建议发展最先进的计算机模拟和实验技术，研究一系列明确定义的和生物学相关的条件下的淀粉样纤维的形成。具体而言，粗粒和所有原子的潜力将被使用和/或开发，以适当地描述粒子间的力。蒙特卡罗和分子动力学模拟将与适当的采样技术相结合，以确定聚集体的结构和稳定性。实验技术将被设计和实施，以表征给定的肽最终形成原纤维或无定形聚集体的程度。这些结果有望揭示淀粉样纤维形成的基本趋势（如氨基酸序列、电荷、疏水性）。这些基本趋势将允许开发的预测能力，为可能的原纤维形成给定的系统（蛋白质结构）和实验设置（溶剂，离子强度，热力学状态，和膜的存在）。通过认识到膜的顺应性作为一个重要的额外的考虑因素，我们希望加深我们的理解膜的组成和界面作为一个可能的控制器的纤维形成的作用。这些系统的实例是胰岛素、溶菌酶、肌红蛋白和STVIIE。将使用提供一系列极性的各种组成的聚合物膜。

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. Recent experimental studies have shown that various degenerative diseases are associated with deposition in the body tissues of insoluble protein aggregates that have a particular (3-sheet conformation. These aggregates have been termed amyloidal fibrils. It has been proposed that the formation of amyloidal fibrils is determined by the nature of the intermediate unfolding species. Moreover, recent experimental studies have shown that amyloidal fibril formation might be favor when proteins are confined in membranes. However, not enough theoretical or experimental considerations have been focused on elucidate the extend of the effect and/or role that membranes plays in the amyloidal fibril formation. This becomes an important issue to address since polymeric protein delivery systems provide a suitable environment for protein fibrillization to occur. We propose to develop state-of-the-art computer simulations and experimental techniques to study the formation of the amyloidal fibrils under a series of well-defined and biologically relevant conditions. Specifically, coarse-grained and all-atom potentials will be used and/or develop to properly describe the interparticle forces. Monte Carlo and Molecular Dynamic simulations will be coupled to appropriate sampling techniques to determine the structure and stability of the aggregates. Experimental techniques will be designed and implemented to characterize the extend to which a given peptide will eventually form fibrils or amorphous aggregates. The results are expected to uncover basic trends (such as amino acid sequence, charge, ad hydrophobicity) on the molecular description of amyloidal fibril formations. These basic trends will permit the development of prediction capabilities for the possible fibril formation given the system (protein structure) and the experimental set-up (solvent, ionic strength, thermodynamic state, and presence of a membrane). By recognizing membrane compliance as an important additional consideration, we expect to deepen our understanding of the role of membrane composition and interface as a possible controller of fibrilar formation. Examples of these systems are insulin, lysozime, myoglobin, and STVIIE. Polymeric membranes of various composition, that provide a range of polarities, will be used.