Dynamic Interactions between Intrinsically Disordered Proteins and Curved Membrane Surfaces

本质无序蛋白质与弯曲膜表面之间的动态相互作用

• 批准号: 10708024
• 负责人: Wade F Zeno
• 金额: $ 39.44万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-22 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10708024
• 关键词: 3-Dimensional; Adsorption; Affect; Behavior; Binding; Biological; Biophysical Process; Biophysics; Cell physiology; Defect; Disease; Endocytic Vesicle; Environment; Equilibrium; Fluorescence Microscopy; Goals; Human; Kinetics; Knowledge; Laboratories; Literature; Measurement; Measures; Membrane; Membrane Protein Traffic; Mission; Phase; Protein Engineering; Proteins; Proteome; Public Health; Research; Research Project Grants; Signal Transduction; Structure; Surface; Synaptic Vesicles; System; Techniques; Testing; Thermodynamics; United States National Institutes of Health; Visualization; Work; human disease; interest; malignant neurologic neoplasms; millisecond; nervous system disorder; programs; protein aggregation; protein structure; sensor; three dimensional structure; trafficking; two-dimensional

Project Summary/Abstract. Intrinsically Disordered Proteins (IDPs) represent approximately 40% of the human proteome and are implicated in a large number of human diseases, including neurological disorders and cancer. Therefore, the biological relevance of IDPs has garnered substantial interest over the last decade. IDPs often interact with curved membranes to form structures that are essential to cellular physiology, such as synaptic and endocytic vesicles. These interactions are facilitated by membrane curvature sensing. The PI recently discovered that IDPs are potent sensors of membrane curvature. This discovery is a substantive departure from the predominant structure-function paradigm, as IDPs lack fixed three-dimensional structure and are often incorrectly assumed to also lack biophysical functionality. The curvature sensitivity of IDPs, as well as many other types of proteins, is normally studied at thermodynamic equilibrium. However, membrane-interacting proteins exist in a dynamic equilibrium between their membrane-bound and membrane-unbound states. It can take minutes to achieve thermodynamic equilibrium between proteins and membranes, but cellular processes, such as cell signaling, occur anywhere between milliseconds to seconds. It is clear from this mismatch in timescales that when thermodynamic equilibrium alone is considered, dynamic information that is pertinent to the timescale of cellular processes is omitted. Little to no literature exists that examines this phenomenon, likely owing to the difficulty associated with achieving such experimental measurements. Thus, dynamic interactions between proteins and curved membrane structures are poorly understood. Using their expertise in quantitative fluorescence microscopy and protein engineering, the goal of the PI's laboratory is to develop and apply techniques and strategies that will allow for direct visualization and characterization of dynamic interactions between IDPs and curved membrane structures. The PI's future research program contains 3 overarching research projects. Work in Project 1 will evaluate the extent to which protein structure influences adsorption and desorption kinetics, testing the working hypothesis that curved membranes affect various protein structures differently. Work in Project 2 will evaluate the impact of protein networks on the binding dynamics of IDPs, answering questions about the influence of protein multivalency on dynamic behavior. Work in Project 3 will develop experimental techniques and strategies that mimic the intracellular environment, answering questions about dynamic interactions between IDPs and curved membrane substrates that occur in the presence of two- dimensional, phase separated protein mixtures on the membrane surface or three-dimensional protein aggregates in the bulk solution. As previously mentioned, our current understanding of the interactions between proteins and curved membranes was derived from systems in which the partitioning of proteins was measured after thermodynamic equilibrium was achieved. In contrast, the proposed work will fill a key gap in existing knowledge by directly observing and quantifying dynamic interactions between proteins and curved membranes.

项目概要/摘要。内源性紊乱蛋白（IDP）占人类蛋白质的约40%。 蛋白质组，并涉及大量的人类疾病，包括神经系统疾病和癌症。 因此，国内流离失所者的生物相关性在过去十年中引起了极大的兴趣。国内流离失所者往往 与弯曲的膜相互作用以形成细胞生理学所必需的结构，例如突触和 内吞囊泡这些相互作用通过膜曲率感测来促进。私家侦探最近发现 IDP是膜曲率的有效传感器。这一发现是一个实质性的背离， 主要的结构-功能范式，因为国内流离失所者缺乏固定的三维结构， 假设也缺乏生物物理功能。IDP的曲率敏感性，以及许多其他类型的 蛋白质，通常在热力学平衡下进行研究。然而，膜相互作用蛋白存在于一种 它们的膜结合和膜非结合状态之间的动态平衡。可能需要几分钟 在蛋白质和膜之间实现热力学平衡，但细胞过程，如细胞 信号，发生在毫秒到秒之间的任何地方。从这种时间尺度上的不匹配可以清楚地看出， 当仅考虑热力学平衡时，与时间尺度相关的动态信息 省略了细胞过程。几乎没有文献研究这种现象，可能是由于 与实现这种实验测量相关的困难。因此， 人们对蛋白质和弯曲的膜结构知之甚少。利用他们在定量方面的专业知识 荧光显微镜和蛋白质工程，PI的实验室的目标是开发和应用 技术和战略，将允许直接可视化和动态交互特性 和弯曲的膜结构之间的关系。PI的未来研究计划包含3个总体 研究项目。项目1的工作将评估蛋白质结构影响吸附的程度， 解吸动力学，测试弯曲膜影响各种蛋白质结构的工作假设 不同.项目2的工作将评估蛋白质网络对国内流离失所者结合动力学的影响， 回答关于蛋白质多价性对动力学行为的影响的问题。项目3将 开发模拟细胞内环境的实验技术和策略，回答问题 关于在存在两种- 膜表面上的三维相分离蛋白质混合物或三维蛋白质 在本体溶液中聚集。如前所述，我们目前对 蛋白质和弯曲的膜是从测量蛋白质分配的系统中得到的 达到热力学平衡后。相比之下，拟议的工作将填补现有的一个关键空白， 通过直接观察和量化蛋白质和弯曲膜之间的动态相互作用来获得知识。