Deciphering the conformational mechanisms of nascent membrane protein folding

细胞膜是一种动态结构，主要由蛋白质和脂质组成，起分隔细胞的作用，为细胞及其细胞器的外部环境提供屏障。整体膜蛋白存在于细胞膜内，负责各种动态过程，如感觉、细胞调节和细胞间粘附。膜蛋白的功能和表达水平将在很大程度上决定离子组成，从而决定特定细胞类型的代谢水平，使它们成为所有生命所必需的。膜蛋白必须“正确”折叠才能发挥功能。这项研究计划的主要目的是了解新生膜蛋白如何折叠。膜蛋白折叠的化学原理在其生产过程中，在细胞膜的背景下是知之甚少。研究膜蛋白是一项艰巨的任务，因为膜蛋白的难治性和疏水性，与它们的可溶性蛋白质对应部分相比；相比之下，它们的细胞定位和在膜内折叠需要额外的蛋白质机制。了解相关过程将增强我们对细胞如何获得“正确”折叠和功能的膜蛋白的理解，并假设“不正确”错误折叠和聚集的膜蛋白是如何形成的——这是一个对细胞有毒的过程。因此，能够反映细胞过程的可靠分析的发展将使辅助因子、突变和药物对膜蛋白折叠过程的影响成为可能。此外，还有一个关键的目标是开发方法，以获得结构洞察膜蛋白事件使用先进的化学工具和技术，如氢-氘交换质谱。这项研究计划在伦敦国王学院化学系Paula Booth教授的实验室进行。该研究将涉及生产能够在体外生产、插入和折叠膜蛋白的系统，并开发用于这些过程的结构评估的方法，重点是使用氢-氘交换质谱法。

Cellular membranes are dynamic structures consisting mostly of protein and lipid which act to compartmentalise the cell, providing barriers to the external environments of the cell and its organelles. Integral membrane proteins reside within a cellular membrane and are responsible for a variety of dynamic processes, such as sensation, cellular regulation, and cell-to-cell adhesion. A membrane protein's functional capability and their level of expression will largely decide the ionic composition, and therefore the metabolic levels of a given cell type, making them essential for all life. Membrane proteins must be folded 'correctly' to become functional. The key aim of the research proposal is to understand how nascent membrane proteins fold. The chemical principles of membrane protein folding during their production and in the context of a cellular membrane are poorly understood. Investigating membrane proteins is a difficult task due to the intractable and hydrophobic nature of membrane proteins, compared to their soluble protein counter parts; with additional protein machinery being required for their cellular localisation and folding within the membrane, in comparison. To understand the processes involved would enhance our understanding on how the cell obtains 'correctly' folded and functional membrane proteins, and postulate on how 'incorrectly' misfolded and aggregated membrane proteins are formed - a toxic process for a cell. Consequently, development of robust assays that reflect the cellular processes will enable the influence of co-factors, mutations and drugs on the process of membrane protein folding. Moreover, there is a key aim to develop methodologies to gain structural insight into membrane protein events using advanced chemical tools and techniques, such as hydrogen-deuterium exchange mass spectrometry.The research is proposed to take place at the King's College London, Department of Chemistry, within the laboratory of Professor Paula Booth. The research will involve producing systems capable of both membrane protein production, insertion and folding in vitro and developing methodologies for the structural assessment of these processes with strong focus on using hydrogen deuterium exchange mass spectrometry.