STRUCTURE, FUNCTION, DYNAMICS OF CHAPERONE DOMAINS

伴侣蛋白有助于生物分子的运输、后处理、解缠和折叠，例如蛋白质，可能还有体内的核酸。这一功能可以被视为信号转导的最后一步，因为表达但不正确折叠的生物分子对细胞没有任何功能。因此，详细了解伴侣蛋白对体内折叠过程的影响对于理解复杂的细胞调控和生长周期具有重要意义。我们建议使用一个小的14 kDa的Hsp70结构来详细地研究Hsp70-热休克-伴侣蛋白与多肽和其他蛋白质的相互作用。这一规模缩小是在前一时期对较大领域的结构研究的基础上构思的。我们的目标是了解这个Hsp70结构域与一个可管理大小的复合体中底物蛋白之间的相互作用。这将揭示伴侣蛋白如何帮助解开错误折叠的蛋白质，以及是什么定义了易于折叠的结构。一种新发现的热休克蛋白Hsp15，可能是发育中的核糖体的一部分，显示出RNA特异性结合和适度的RNA伴侣活性。我们打算从结构、动力学和能量学的角度详细描述该蛋白质与RNA之间的相互作用。这将有助于更好地理解RNA-蛋白质相互作用的基本原理。通过比较Hsp15和Hsp70蛋白的结果，我们旨在了解它们的共同点和不同之处。Hsp15和Hsp70具有伴侣活性的热休克蛋白的特性，但它们的靶底物不同。这些知识将有助于从总体上理解生物分子间的相互作用。

Chaperone proteins aid in the trafficking, post-processing, disentanglement and folding of biomolecules such as proteins and possibly nucleic acids in vivo. This function can be viewed as the last step in signal transduction, as an expressed but improperly folded biomolecule is of no function to the cell. Therefore, detailed understanding of the influences of chaperone proteins on the in-vivo folding process is of importance to the understanding of complicated cellular regulation and growth cycles. We propose to focus on the interaction of Hsp70-heatshock- chaperone proteins with peptides and other proteins in detail using a small 14 kDa Hsp70 construct. This size reduction was conceived on the basis of the structural studies of larger domains in the previous period. We aim to understand the interaction between this Hsp70 domain and a substrate protein in a complex of manageable size. This will reveal how chaperone proteins help disentangle misfolded proteins and what defines folding-prone structures. A newly discovered heatshock protein, Hsp15, which is likely part of the developing ribosome, displays RNA-specific binding and moderate RNA-chaperoning activity. We propose to obtain a detailed description of the interaction between this protein and RNA in terms of structure, dynamics and energetics. This will help better understand the underlying principles of RNA-protein interactions in general. By comparing results on the Hsp15 and Hsp70 proteins, which share the property of being heatshock proteins with chaperone activity, but differ by their target substrates, we aim to learn what the points of similarity and difference are. This knowledge will help understand biomolecular interactions in general.