Structure and Function of Non-Conventional Caveolins

非常规小窝蛋白的结构和功能

• 批准号: 10638902
• 负责人: Anne K Kenworthy
• 金额: $ 73.09万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10638902
• 关键词: Address; Adipose tissue; Biochemical; Biogenesis; Biological; Biological Assay; Biological Process; Biophysics; Cardiovascular Diseases; Cardiovascular Physiology; Cardiovascular system; Caveolae; Caveolins; Cell Adhesion; Cell Differentiation process; Cell membrane; Cell physiology; Cell surface; Cells; Cholesterol; Complex; Cryoelectron Microscopy; Cytoplasm; Data; Defect; Development; Disease; Electron Microscopy; Exhibits; Family; Family member; Geometry; Heart; Homeostasis; Homo; Human; In Vitro; Intracellular Transport; Investigation; Knowledge; Learning; Link; Lipids; Lipodystrophy; Lung; Malignant Neoplasms; Mechanical Stress; Mediating; Membrane; Membrane Biology; Membrane Proteins; Metabolism; Modeling; Molds; Molecular; Morphology; Mus; Muscle; Muscular Dystrophies; Mutation; Natural Selections; Nature; Pathway interactions; Physiological; Physiology; Play; Process; Property; Proteins; Protomer; Research Personnel; Resolution; Role; Shapes; Side; Signal Pathway; Signal Transduction; Structure; Surface; Systemic disease; Testing; Tissues; base; biophysical properties; body system; caveolin 1; caveolin-2; caveolin-3; cell motility; cell type; flasks; insight; mechanotransduction; membrane model; molecular dynamics; particle; protein function; pulmonary arterial hypertension; pulmonary function; sensor; trafficking

Caveolins are a family of unusual membrane proteins that function as key regulators of the cardiovascular system and metabolism. One of their major biological activities is to shape the plasma membrane to form flask-shaped invaginations called caveolae. Defects in caveolins and caveolae have dramatic physiological consequences and disrupt intracellular trafficking, signaling, lipid homeostasis, mechanosensing, and plasma membrane integrity at the cellular level. How caveolins and caveolae regulate so many different cellular functions has remained a mystery for nearly 30 years, in part due to the lack of information about the structure of caveolins. Excitingly, the status quo recently changed. Using cryo-electron microscopy, we have now determined the first high-resolution structure of the caveolin family member responsible for caveolae biogenesis outside of muscle, caveolin-1 (CAV1). Consisting of 11 tightly packed protomers arranged in a disc, the structure represents an oligomeric state of the protein that serves as the fundamental building block of caveolae. It is thus now possible to begin to address how caveolae form and function at a mechanistic level. Here, we propose to build on lessons learned from determining the structure of CAV1 to tackle another ongoing conundrum in the field. Either as a consequence of disease-associated mutations or as a result of natural selection, some caveolins are unable to generate caveolae on their own. Remarkably, these “non- conventional” caveolins can still have profound effects on caveolae assembly and dynamics and even exert distinct biological functions. How does this happen? To gain insight into this long-standing question, we propose to compare and contrast the properties of CAV1 with caveolin-2 (CAV2), an evolutionarily conserved, naturally occurring example of a caveolin that can only form caveolae in the presence of CAV1 and is required for normal physiological function of the lung. Using a combination of structural, biochemical, biophysical, computational, and cell biological assays, we will 1) determine how the unique structural features of CAV2 dictate its interactions with itself, CAV1, and other proteins and 2) study mechanisms used by caveolin complexes to associate with and bend membranes and mediate plasma membrane homeostasis. These studies will provide critical insights into how caveolins interact with themselves and one another to form the building blocks of caveolae as well as how the distinct structural features of caveolin family members dictate their biological functions by controlling their repertoire of interacting proteins and lipids. On a more fundamental level, the proposed investigations will test new ideas about how proteins insert into membranes and how this influences their ability to mold membrane morphology, composition, and function.

Caveolins 是一类不寻常的膜蛋白，充当心血管的关键调节因子 它们的主要生物活动之一是塑造质膜以形成。 称为小凹的烧瓶状内陷和小凹的缺陷具有显着的生理功能。 后果并破坏细胞内运输、信号传导、脂质稳态、机械传感和血浆 细胞水平上的膜完整性。小窝和小窝如何调节许多不同的细胞。 近 30 年来，其功能一直是个谜，部分原因是缺乏有关其结构的信息 令人兴奋的是，最近使用冷冻电子显微镜，我们已经改变了现状。 确定了造成小窝的小窝蛋白家族成员的第一个高分辨率结构 肌肉外的生物发生，caveolin-1 (CAV1) 由 11 个排列紧密的原聚体组成。 圆盘，该结构代表蛋白质的寡聚状态，作为蛋白质的基本构建块 因此，现在可以开始在机械层面上解决小窝的形成和功能问题。 在这里，我们建议借鉴确定 CAV1 结构的经验教训来解决另一个问题 该领域持续存在的难题，要么是由于疾病相关突变的结果，要么是由于 自然选择，一些小窝无法自行产生小窝，值得注意的是，这些“非-”。 传统的“小窝”仍然可以对小窝的组装和动力学产生深远的影响，甚至发挥作用 为了深入了解这个长期存在的问题，我们需要了解不同的生物学功能。 建议比较和对比 CAV1 与 Caveolin-2 (CAV2) 的特性，CAV2 是一种进化上保守的、 天然存在的小窝蛋白的例子，它只能在 CAV1 存在的情况下形成小窝蛋白，并且是必需的 结合结构、生物化学、生物物理、 通过计算和细胞生物学测定，我们将 1) 确定 CAV2 的独特结构特征如何 决定其与自身、CAV1 和其他蛋白质的相互作用，以及 2) 研究 Caveolin 使用的机制 复合物与膜结合并弯曲膜并介导质膜稳态。 研究将为小窝蛋白如何与自身和彼此相互作用以形成 小窝的组成部分以及小窝家族成员的独特结构特征如何决定 通过控制相互作用的蛋白质和脂质的全部功能来控制它们的生物学功能。 基础层面上，拟议的研究将测试有关蛋白质如何插入膜的新想法 以及这如何影响它们塑造膜形态、组成和功能的能力。