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。内在无序蛋白质 (IDP) 约占人类蛋白质的 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，国内流离失所者的生物学相关性在过去十年中引起了人们的广泛关注。国内流离失所者经常 与弯曲的膜相互作用，形成细胞生理学必需的结构，例如突触和 内吞囊泡。膜曲率传感促进了这些相互作用。 PI最近发现 IDP 是膜曲率的有效传感器。这一发现与之前的发现有实质性的不同 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，并且经常被错误地 假定也缺乏生物物理功能。 IDP 以及许多其他类型的曲率敏感性 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 它们的膜结合状态和膜非结合状态之间的动态平衡。可能需要几分钟时间 实现蛋白质和膜之间的热力学平衡，但细胞过程，例如细胞 信号发生在毫秒到秒之间的任何时间。从这种时间尺度的不匹配可以清楚地看出 当单独考虑热力学平衡时，与时间尺度相关的动态信息 细胞过程被省略。几乎没有文献研究这种现象，可能是由于 与实现此类实验测量相关的困难。因此，之间的动态相互作用 人们对蛋白质和弯曲膜结构知之甚少。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实验室的目标是开发和应用 允许动态交互的直接可视化和表征的技术和策略 IDP 和弯曲膜结构之间。 PI 的未来研究计划包含 3 个总体性内容 研究项目。项目 1 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 不同。项目 2 的工作将评估蛋白质网络对 IDP 结合动态的影响， 回答有关蛋白质多价对动态行为的影响的问题。项目 3 中的工作将 开发模拟细胞内环境的实验技术和策略，回答问题 关于 IDP 和弯曲膜基底之间在存在两种情况下发生的动态相互作用 膜表面上的维度、相分离的蛋白质混合物或三维蛋白质 本体溶液中的聚集体。如前所述，我们目前对两者之间相互作用的理解 蛋白质和弯曲膜源自测量蛋白质分配的系统 达到热力学平衡后。相比之下，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和弯曲膜之间的动态相互作用来获取知识。