DETERMINANTS OF A SIMPLE MEMBRANE PROTIN TOPOLOGY

提出的这项研究旨在更好地了解 膜蛋白获得它们的最终结构。这些实验将会 研究四个序列元件在建立细胞膜中的作用 大肠杆菌丝氨酸化学感受器的拓扑结构。四个序列元素 是蛋白质的两个跨膜片段(tm1和tm2)，一种赖氨酸 与TM2的C-末端相邻的残基(赖氨酸-215)和13 残基两亲性序列位于8-20个残基的C端至TM2之间。 拟议的实验将识别和分析拓扑 突变改变不同序列元件的后果。这些 研究将有助于确定元素的主要顺序要求 以发挥作用，并将区分不同型号的功能。 更多的实验将调查不同的 序列元件在产生丝氨酸的过程中相互作用 化学感受器拓扑学。

The research proposed aims to provide a better understanding of how membrane proteins acquire their final structures. The experiments will examine the roles of four sequence elements in establishing the membrane topology of the E. coli serine chemoreceptor. The four sequence elements are the protein's two membrane-spanning segments (tm1 and tm2), a lysine residue adjacent to the C-terminal end of tm2 (lysine-215), and a 13 residue amphipathic sequence situated 8-20 residues C-terminal to tm2. The proposed experiments will identify and analyze the topological consequences of mutations altering the different sequence elements. These studies will help define the primary sequence requirements for the elements to function, and will distinguish between models for how they function. Additional experiments will investigate the manner in which the different sequence elements interact with each other in generating the serine chemoreceptor topology.