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.

项目摘要/摘要。本质上无序的蛋白质（IDP）约占人类的40％ 蛋白质组，与许多人类疾病有关，包括神经系统疾病和癌症。 因此，在过去的十年中，IDP的生物学相关性引起了巨大的兴趣。经常IDP 与弯曲的膜相互作用，形成对细胞生理必不可少的结构，例如突触和 内吞囊泡。这些相互作用是通过膜曲率传感促进的。 PI最近发现了 该IDP是膜曲率的有效传感器。这一发现与 主要的结构 - 功能范式，因为IDP缺乏固定的三维结构，并且通常是错误的 假定也缺乏生物物理功能。 IDP的曲率灵敏度以及许多其他类型的 通常在热力学平衡下研究蛋白质。但是，膜相互作用蛋白存在于 它们的膜结合和膜无态状态之间的动态平衡。可能需要几分钟 在蛋白质和膜之间达到热力学平衡，但是细胞过程，例如细胞 信号传导发生在毫秒到几秒钟之间的任何地方。从这个时间标准中的不匹配可以明显看出 当仅考虑热力学平衡时，与时间尺度有关的动态信息 省略了蜂窝过程。几乎没有文学作用来检验这种现象，这可能是由于 与实现此类实验测量相关的困难。因此，动态相互作用 蛋白质和弯曲的膜结构知之甚少。利用他们的定量专业知识 荧光显微镜和蛋白质工程，PI实验室的目标是开发和应用 将允许直接可视化和表征动态相互作用的技术和策略 在IDP和弯曲的膜结构之间。 PI的未来研究计划包含3个总体 研究项目。项目1中的工作将评估蛋白质结构影响吸附和 解吸动力学，测试弯曲膜影响各种蛋白质结构的工作假设 对不同。项目2中的工作将评估蛋白质网络对IDP的结合动力学的影响， 回答有关蛋白质多价对动态行为的影响的问题。在项目3中工作将 开发模仿细胞内环境的实验技术和策略，回答问题 关于在两种存在的情况下发生的IDP和弯曲膜底物之间的动态相互作用 尺寸，相分离的蛋白质混合物在膜表面或三维蛋白 散装解决方案中的聚集体。如前所述，我们目前对 蛋白质和弯曲膜源自该系统，其中测量了蛋白质的分配 实现热力学平衡后。相反，拟议的工作将填补现有的关键空白 通过直接观察和量化蛋白质与弯曲膜之间的动态相互作用来实现知识。