Spectroscopic Study of Protein Folding Dynamics

描述(申请人提供)：蛋白质通过其线性多肽链的特定折叠获得其独特的功能。错误折叠会导致许多疾病，如囊性纤维化和各种神经退行性疾病。尽管人们已经做了大量的工作来研究蛋白质的二级和三级结构是如何形成的，研究蛋白质折叠的实验和理论技术也在不断完善，但对蛋白质折叠的定量和预测理解仍然是不可能的。仍然有许多基本的问题，例如：特定的和非特定的与环境的相互作用如何决定折叠路径、能量景观的粗糙度以及从热和动力学上可访问的构象底物？在拥挤的环境和/或膜中，特定的构象和折叠事件在什么时间范围内发生？解决这些问题需要进一步研究时间分辨光谱技术，以提供必要的时间分辨率和结构敏感性。因此，拟议研究的主要目标是开发新的光谱方法和新的构象探针，可用于对瞬时折叠物种及其在广泛时间尺度上的动力学进行详细的结构解释。计划进行一系列全面的实验，以获得对蛋白质折叠问题的各个方面的新见解，以及膜蛋白质的结构-动力学-功能关系。其技术目标是：(A)开发用于蛋白质折叠和结合研究的新的光谱探针和方法；(B)研究大分子拥挤和限制如何影响蛋白质折叠和聚集的动力学；(C)研究膜蛋白质折叠的早期动力学事件；(E)探索膜蛋白质功能的构象动力学。实现这些特定的目标，不仅应该导致新的实验方法的各种生物学应用，而且新的发现将有助于提高我们对蛋白质折叠的许多基本问题的理解，从而对该领域做出实际和直接的贡献。

DESCRIPTION (provided by applicant): Proteins acquire their unique functions through specific folding of their linear polypeptide chains. Misfolding results in numerous diseases, such as cystic fibrosis and various neurodegenerative disorders. Although a great deal of work has been done to investigate how the secondary and tertiary structures of proteins are formed and both experimental and theoretical techniques for studying protein folding are continually becoming more refined, a quantitative and predictive understanding of protein folding is still not attainable. There are still many fundamental questions, such as: How do specific and nonspecific interactions with the surroundings determine the folding pathways, the roughness of the energy landscape, and the thermally and kinetically accessible conformational substrates? On what range of timescales do particular conformational and folding events occur in crowded environments and/or membranes? Addressing these questions presents the need for further studies with time-resolved spectroscopic techniques that can provide the necessary time resolution and structural sensitivities. The principal objective of the proposed research is therefore to develop new spectroscopic methods and new conformational probes that can be used to generate detailed structural interpretations of the transient folding species and their dynamics over a wide range of timescales. A comprehensive set of experiments are planned to gain new insight into the understanding of various aspects of the protein folding problem, as well as the structure-dynamics-function relationship of membrane proteins. The technical goals are to: (a) develop new spectroscopic probes and methods for protein folding and binding studies; (b) investigate how macromolecular crowding and confinement affect the kinetics of protein folding and aggregation; (c) study the early kinetic events in membrane protein folding; (e) probe the conformational dynamics underlying membrane protein function. Achieving these specific aims should result in not only new experimental methods for various biological applications, but also new findings that would help improve our understanding of many fundamental issues in protein folding, thus making practical and direct contributions to the field.