Membrane shape transition control in cellular membrane trafficking phenomena

细胞膜运输现象中的膜形状转变控制

• 批准号: 9120160
• 负责人: Tobias Baumgart
• 金额: $ 47.88万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9120160
• 关键词: Actins; Adaptor Signaling Protein; Address; Alzheimer' s Disease; Area; Automobile Driving; Binding; Calcium; Cell membrane; Cell physiology; Cells; Cellular Membrane; Cellular Structures; Centronuclear myopathy; Clathrin Adaptors; Communicable Diseases; Crowding; Data; Descriptor; Disease; Endocytosis; Evaluation; Filopodia; Fluorescence; Generations; Goals; Human; Huntington Disease; In Vitro; Inflammatory; Ions; Laboratories; Lead; Lipids; Mammalian Cell; Membrane; Membrane Protein Traffic; Membrane Proteins; Metabolic Diseases; Micromanipulation; Molecular; Molecular Motors; Mutation; Organelles; Parkinson Disease; Pathway interactions; Peripheral; Phase; Phosphorylation; Problem Solving; Process; Proteins; Regulation; Research; Shapes; Signal Transduction; Tertiary Protein Structure; Testing; Therapeutic; Yeasts; alpha synuclein; amphiphysin; apical membrane; biophysical model; cancer type; design; epsin; experience; human disease; improved; insight; interest; membrane model; neglect; nervous system disorder; pathogen; polymerization; protein function; protein protein interaction; public health relevance; receptor; research study; scaffold; synergism; tool; trafficking

 DESCRIPTION (provided by applicant): Membrane shape is important not only as a static aspect of size and structure of cells and organelles, but dynamically changes in numerous processes such as membrane signaling and trafficking. At the plasma membrane, the formation of in- and exvaginations, in processes such as endocytosis and the generation of filopodia, respectively, are some of the most important phenomena where membrane curvature is modulated. The discovery of a class of proteins which contain crescent shaped scaffolds called BAR (Bin/amphiphysin/Rvs) domain proteins, has prompted a growing interest in understanding how proteins couple with membrane curvature. BAR domains are found in numerous proteins implicated in human disease, and many contain disease driving mutations and/or show altered expression levels under pathological conditions. Additional peripheral proteins that are related to membrane curvature include intrinsically disordered proteins such as α-synuclein, as well as ENTH domain-containing proteins such as epsin, both of which are believed to be involved in membrane trafficking phenomena. Endocytosis is the primary mechanism by which pathogens enter cells. To improve the understanding of the mechanism and regulation of this process therefore is a matter of primary biomedical relevance. However, despite the fact that more than 90000 research contributions have investigated endocytosis alone, the mechanisms for initiation of this process are not understood. This is due in part to the fact that in cells numerous endocytic mechanisms operate in parallel and that the degree for experimental control of key parameters in cells is limited. The goal of this project is to understand how membrane shape transitions are regulated in processes such as endocytosis. In order to achieve this goal, we have developed an experimental biophysical model membrane approach that allows us to determine the conditions under which membranes undergo shape transitions. With the help of this tool, which consists of a combined micro- manipulation/fluorescence approach that is presently used exclusively in our laboratory, we will investigate mechanisms of the function of the many proteins involved in endocytosis, and isolate key modulators of membrane shape transitions. We already have developed a theoretical framework that will facilitate mechanistic interpretation of our findings. While plasma membranes experience significant asymmetry with respect to transmembrane ion and lipid distributions, model membrane research has largely focused on symmetric membranes. We will overcome this limitation and determine to what extent membrane asymmetry, which will include cytoskeletal interactions, contributes to the function of peripheral proteins in shaping membranes. Overall this project will provide far-reaching insight into the mechanisms by which peripheral proteins deform membranes under healthy and pathological conditions.

 描述（由申请人提供）：膜形状不仅作为细胞和细胞器的大小和结构的静态方面很重要，而且在许多过程（如膜信号传导和运输）中动态变化。在质膜上，分别在诸如内吞作用和丝状伪足的产生等过程中形成内陷和外陷，是膜曲率被调制的一些最重要的现象。一类含有新月形支架的蛋白质（称为BAR（Bin/amphiphysin/Rvs）结构域蛋白）的发现促使人们对理解蛋白质如何与膜曲率耦合越来越感兴趣。BAR结构域存在于与人类疾病有关的许多蛋白质中，并且许多含有疾病驱动突变和/或在病理条件下显示改变的表达水平。其他外周蛋白质与 膜曲率包括固有无序的蛋白质如α-突触核蛋白，以及含有ENTH结构域的蛋白质如epsin，这两者都被认为参与膜运输现象。 内吞作用是病原体进入细胞的主要机制。因此，提高对这一过程的机制和调节的理解是一个具有重要生物医学意义的问题。然而，尽管事实上，超过90000的研究成果已调查内吞作用单独，启动这一进程的机制还不清楚。这部分是由于在细胞中许多内吞机制并行运作，并且细胞中关键参数的实验控制程度有限。的 这个项目的目标是了解在细胞内吞作用等过程中，细胞膜形状的转变是如何被调节的。为了实现这一目标，我们已经开发了一种实验生物物理模型膜的方法，使我们能够确定膜进行形状转变的条件下。在这个工具的帮助下，它包括一个组合的显微操作/荧光的方法，目前只在我们的实验室中使用，我们将研究机制的许多蛋白质参与内吞作用的功能，并分离膜形状转换的关键调节器。我们已经建立了一个理论框架，这将有助于对我们的发现进行机械解释。 虽然质膜经历显着的不对称性，跨膜离子和脂质分布，模型膜的研究主要集中在对称膜。我们将克服这一限制，并确定在何种程度上膜的不对称性，这将包括细胞骨架的相互作用，有助于在塑造膜的外周蛋白质的功能。总的来说，这个项目将提供深远的洞察机制，外周蛋白质变形膜在健康和病理条件下。