Regulation of KRAS plasma membrane targeting by defined glycosphingolipids.

通过特定的鞘糖脂调节 KRAS 质膜靶向。

• 批准号: 10718459
• 负责人: Alemayehu A. Gorfe
• 金额: $ 40万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10718459
• 关键词: Anabolism; Animal Model; Apoptosis; Binding; Biological Models; Biophysics; Biosensor; C-terminal; Cancer Model; Carrier Proteins; Cell Proliferation; Cell membrane; Complex; Coupled; Couples; Coupling; Dependence; Electron Microscopy; Endoplasmic Reticulum; Environment; Enzymes; Esters; Feeds; GTP Binding; Genetic; Glucose; Glycolysis; Glycosphingolipids; Grant; Growth Factor Receptors; Guanosine Triphosphate Phosphohydrolases; In Vitro; KRAS oncogenesis; KRAS2 gene; Lead; Lecithin; Link; Lipids; Lysine; MEKs; Malignant neoplasm of lung; Membrane; Membrane Biology; Membrane Lipids; Membrane Proteins; Metabolic; Metabolism; Methods; Molecular; Mus; Nanostructures; Noise; Oncogenic; Pancreas; Pathologic; Pathway interactions; Phosphatidylethanolamine; Phosphatidylserines; Phospholipids; Proteins; Proteolipids; Regulation; Role; Signal Pathway; Signal Transduction; Site; Specificity; Structure; Surface; Testing; Therapeutic; Transmembrane Transport; Warburg Effect; aerobic glycolysis; experimental study; genetic approach; high resolution imaging; imaging approach; in vivo; inhibitor; insight; interdisciplinary approach; lipid transport; molecular dynamics; mouse model; nanocluster; nanoscale; novel; pancreatic cancer model; pharmacologic; phosphatidylinositol 4-phosphate; reconstitution; recruit; synergism; synthetic enzyme; transmission process; tumorigenesis

PROJECT SUMMARY KRAS operates as a molecular switch that oscillates between an active GTP-bound and inactive GDP-bound state. Active KRAS proteins are required to localize to the plasma membrane within a defined lipid environment to be functional. Oncogenic KRAS induces metabolic dependence on aerobic glycolysis, a phenomenon known as the Warburg effect. We recently discovered that aerobic glycolysis, by generating a subset of outer leaflet glycosphingolipids (GSL), controls KRAS plasma membrane (PM) interactions and therefore KRAS oncogenesis. Blocking GSL metabolism, using multiple methods including glucose deletion, pharmacological inhibition and genetic deletion of selected GSL synthetic enzymes all mislocalize KRAS from the PM. Deletion of key enzymes of the GSL biosynthetic pathways abrogated KRAS oncogenesis in vitro and in vivo. Building on these exciting findings, we developed our central hypothesis: that a subset of defined glycosphingolipids regulates localization and nanoscale organization of KRAS through controlling the lipid composition on the PM and lipid transport at PM-ER membrane contact sites. We will test to what extent do GSLs operate as spatial organizers of the inner PM and ER-PM contacts sites in Aim1 by using a variety of lipid biosensor and high- resolution imaging. In Aim 2, we will employ genetic approaches, lipid reconstitution experiments and molecular dynamics simulation to probe the potential mechanism of inter leaflet coupling between outer leaflet GSLs and inner leaflet phosphatidylserine on the PM. Finally, in Aim 3 we will rigorously test the relevance of this novel glycosphingolipid-centered mechanism in multiple mouse KRAS cancer models. In sum, using a multidisciplinary approach, this proposal will yield new insights into the molecular mechanism of how surface GSLs regulate PM lipid composition and lipid transport, and the role of inter leaflet lipid coupling. This is highly significant to basic membrane biology and biophysics. The connection of GSL metabolism through PM lipid organization to KRAS function will identify a novel vulnerability to KRAS oncogenesis that may have therapeutic potential.

项目总结 KRAS作为一个分子开关，在活跃的GTP结合和不活跃的GDP结合之间振荡 州政府。活性KRAS蛋白需要在特定的脂质环境中定位于质膜 才能发挥作用。致癌KRAS诱导对有氧糖酵解的代谢依赖，这是一种已知的现象 作为华宝效应。我们最近发现，通过产生外叶的子集，有氧糖酵解 鞘糖脂(GSL)控制KRAS质膜(PM)相互作用，从而控制KRAS 致癌作用。阻断GSL代谢，使用多种方法，包括葡萄糖缺失，药理学 选择的GSL合成酶的抑制和基因缺失都使PM中的KRAS错位删除 GSL生物合成途径的关键酶在体外和体内均可抑制KRAS的致癌作用。建房 基于这些令人兴奋的发现，我们提出了我们的中心假设：已定义的神经鞘糖脂的一个子集 通过控制PM上的脂质成分来调节KRAS的定位和纳米结构 PM-ER膜接触部位的脂质转运。我们将测试GSL在多大程度上作为空间操作 Aim1内PM和ER-PM接触部位的组织者通过使用各种脂质生物传感器和高 分辨率成像。在目标2中，我们将使用遗传方法、脂质重建实验和 分子动力学模拟探讨外叶间小叶耦合的可能机制 PM上的GSLS和内叶磷脂酰丝氨酸最后，在目标3中，我们将严格测试 这种新的以鞘糖脂为中心的机制在多个小鼠KRAS癌症模型中。总而言之，使用 多学科的方法，这一提议将对表面如何形成的分子机制产生新的见解 GSLS调节PM的脂质组成和脂质转运，并发挥叶间脂偶联的作用。这是高度 对基础膜生物学和生物物理学具有重要意义。质膜脂质与GSL代谢的关系 KRAS职能组织将确定KRAS肿瘤发生的一个新漏洞，该漏洞可能具有 治疗潜力。