Membrane Targeting by Phosphoinositide-Binding Proteins

磷酸肌醇结合蛋白的膜靶向

• 批准号: 8000135
• 负责人: WONHWA CHO
• 金额: $ 8万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-29 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8000135
• 关键词: Abbreviations; Arts; Binding; Binding Proteins; Biological Assay; Cell membrane; Cell physiology; Cells; Cellular Membrane; Complex; Computing Methodologies; Defect; Development; Diabetes Mellitus; Disease; Fluorescence Microscopy; Grant; Health; In Vitro; Inflammatory; Learning; Link; Lipid Binding; Malignant Neoplasms; Mediating; Membrane; Methodology; Monitor; Pathway interactions; Penetration; Phosphatidylinositols; Play; Property; Protein Binding Domain; Proteins; Regulation; Research; Role; Screening procedure; Signal Pathway; Signal Transduction; Specificity; Stimulus; Techniques; Therapeutic Agents; Time; Vesicle; base; cell growth regulation; cellular imaging; drug development; drug discovery; epsin; human disease; programs; protein activation; protein complex; public health relevance; response; tool; trafficking

DESCRIPTION (provided by applicant): Phosphorylated derivatives of phosphatidylinositol, collectively known as phosphoinositides (PIs), play a key role in the membrane recruitment and activation of cytosolic proteins involved in cell signaling and vesicle trafficking. The majority of PI-responsive proteins contain one or more modular lipid binding domains that specifically recognize PIs. Some of these PI-binding domains not only bind PIs but also induce the deformation of PI-containing membranes. Despite the importance of PI-mediated membrane targeting in health and disease, fundamental understanding of complex mechanisms by which PIs differentially and specifically mediate diverse cellular functions through interactions with these effector domains is still largely lacking. The primary objective of this proposed research is to elucidate the mechanisms by which various PIs mediate cellular processes through interactions with three major types pf effector domains, PX, ENTH, and BAR domains. During the past grating period, we discovered that PIs specifically induce the membrane penetration of many effector domains, thereby modulating the cellular functions and regulation of proteins harboring the domains. We have also developed several new methodologies that will allow for both large-scale and in-depth mechanistic studies of PI-binding and membrane-deforming proteins. With a new paradigm and new methodologies, we will pursue three specific aims in the next project period. First, based on the hypothesis that mammalian PX domains mediate diverse cellular processes through their divergent PI specificities and membrane binding properties, we will determine membrane binding properties of PX domains both comprehensively and systematically to elucidate the complex mechanisms of diverse PX domain-mediated cellular function and regulation. Second, we will investigate the mechanisms by which various PIs induce the membrane penetration, protein self-association, and membrane deformation by ENTH domains. Finally, we will determine how differently several BAR domains and ENTH domains penetrate and deform membranes to understand the basis of complex and highly orchestrated actions of a large number of cytosolic proteins during cellular membrane remodeling. A long-term objective of this program is to apply the principles learned from these studies to the development of new classes of therapeutic agents that can specifically modulate the membrane targeting and activation of PI-binding proteins essential for cell signaling and membrane remodeling. Principal methodologies to be used in these proposed studies are a wide range of biophysical, computational, and structural techniques as well as cell imaging by fluorescence microscopy. PUBLIC HEALTH RELEVANCE: Numerous human diseases, including cancer, diabetes, and inflammatory diseases, are known to be linked to defects in phosphoinositide-mediated cell signaling. Consequently, phosphoinositide signaling pathways are major targets for drug development but the complexity of these pathways has hampered the drug discovery effort. Therefore, understanding the mechanisms underlying complex phosphoinositide signaling pathways will greatly aid in developing new classes of therapeutic agents that can treat diseases caused by dysfunctional phosphoinositide signaling pathways.

描述（由申请人提供）：磷脂酰肌醇的磷酸化衍生物，统称为磷酸肌醇（PIS），在膜募集和激活中涉及细胞信号传导和囊泡运输的胞质蛋白的激活中起关键作用。大多数PI响应蛋白包含一个或多个模块化脂质结合域，这些结合结构域专门识别PI。这些PI结合域中的一些不仅结合了PI，还会诱导含PI的膜的变形。尽管PI介导的膜靶向在健康和疾病中的重要性，但对PIS通过与这些效应子域的相互作用而在很大程度上缺乏通过与这些效应子域的相互作用来差异化介导的各种细胞功能的复杂机制的基本理解。这项拟议的研究的主要目的是阐明各种PI通过与三种主要类型PF效应域，PX，ENTH和BAR结构域相互作用介导细胞过程的机制。在过去的光栅期间，我们发现PIS特异性诱导了许多效应子域的膜渗透，从而调节了具有域的蛋白质的细胞功能和调节。我们还开发了几种新方法，这些方法将允许对PI结合和膜形成蛋白质的大规模和深入的机械研究。有了新的范式和新方法，我们将在下一个项目时期实现三个特定目标。首先，基于以下假设：哺乳动物PX结构域通过其不同的PI特异性和膜结合特性介导了多样的细胞过程，我们将在全面和系统上确定PX结构域的膜结合特性，以阐明PX域域介导的细胞功能和调节的复杂机制。其次，我们将研究各种PI诱导膜渗透，蛋白质自我关联和膜变形的机制。最后，我们将确定多个条形域和ENTH结构域在细胞膜重塑期间的复杂且精心策划的大量胞质蛋白的复杂和精心策划的作用的基础。该计划的一个长期目标是将从这些研究学到的原则应用于新的治疗剂的开发，这些治疗剂可以专门调节膜靶向和激活PI结合蛋白对细胞信号传导和膜重塑所必需的蛋白质的激活。这些提出的研究中要使用的主要方法是广泛的生物物理，计算和结构技术以及荧光显微镜的细胞成像。公共卫生相关性：已知许多人类疾病，包括癌症，糖尿病和炎症性疾病，与磷酸肌醇介导的细胞信号传导的缺陷有关。因此，磷酸肌醇信号通路是药物发育的主要目标，但是这些途径的复杂性阻碍了药物发现的工作。因此，了解复杂磷酸肌醇信号通路的基础机制将极大地有助于开发新的类型的治疗剂，这些治疗剂可以治疗由功能失调的磷酸肌醇信号通路引起的疾病。