Structural basis for Rab GTPase regulated membrane trafficking

Rab GTPase 调节膜运输的结构基础

• 批准号: 8652320
• 负责人: David G Lambright
• 金额: $ 35.86万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8652320
• 关键词: Acceleration; Animal Model; Architecture; Arginine; Bacterial Infections; Binding; Binding Sites; Biogenesis; C-terminal; Cell physiology; Cells; Complex; Development; Diabetes Mellitus; Disease; Epitopes; Etiology; Eukaryotic Cell; Family; Fingers; GTP Binding; GTPase-Activating Proteins; Glutamine; Goals; Golgi Apparatus; Gram-Negative Bacteria; Guanine Nucleotide Exchange Factors; Guanosine Triphosphate; Guanosine Triphosphate Phosphohydrolases; Hydrolysis; Infection; Legionella; Legionella pneumophila; Link; Lung; MADD gene; Malignant Neoplasms; Maps; Melanosomes; Membrane; Membrane Biology; Membrane Protein Traffic; Molecular; Molecular Motors; Mono-S; Nucleotides; Organelles; Orphan; Orthologous Gene; Output; Pathway interactions; Phosphatidylinositols; Process; Proteins; Recruitment Activity; Research; Signal Transduction; Site; Sorting - Cell Movement; Staging; Structure; System; Tertiary Protein Structure; Testing; Therapeutic Intervention; Transmembrane Domain; Type IV Secretion System Pathway; Vacuole; Virus Diseases; base; cell type; inositol 4-phosphate; insight; late endosome; macrophage; microbial; pathogen; protein function; public health relevance; rab GTP-Binding Proteins; trafficking

DESCRIPTION (provided by applicant): Rab GTPases are key master regulators of membrane maturation and trafficking throughout the endomembrane system of eukaryotic cells. The function of Rab GTPases depends on a conformational switch cycle between 'inactive' (GDP-bound) and 'active' (GTP-bound) states. Activation and deactivation are tightly controlled by GDP/GTP exchange factors (GEFs) and GTPase activating proteins (GAPs) that accelerate the intrinsically slow rates of nucleotide exchange and GTP hydrolysis. Active Rab GTPases interact with diverse effectors involved in all stages of membrane trafficking. The functional outputs of active Rab GTPases are integrated through multivalent effectors with multiple Rab binding sites. Active Rab GTPases also recruit GEFs or GAPs for downstream or upstream Rab GTPases to coordinate successive trafficking stages and facilitate membrane maturation. The overall goal of this proposal is to understand the structural and molecular bases underlying membrane recruitment of Rab GEFs and GAPs, selective activation and deactivation of Rab GTPases following recruitment, and manipulation of these host process by microbial pathogens. Specifically, we will combine crystallographic, mutational and cell based analyses with quantitative Rab family recognition profiles to investigate the structural and molecular bases for: (Aim 1) recruitment and Rab recognition/activation by DENN and Vps9 domain GEFs; (Aim 2) recruitment and Rab recognition/activation by TBC domain GAPs; (Aim 3) manipulation of host Rab GTPases by Legionella pneumophila. Successful completion of these aims will deliver new insights into poorly characterized molecular interaction networks and structural mechanisms that underpin Rab GTPase-regulated membrane biology in normal and pathogenic conditions.

描述（由申请人提供）：Rab GTP 酶是真核细胞内膜系统膜成熟和运输的关键主调节因子。 Rab GTPases 的功能取决于“非活性”（GDP 结合）和“活性”（GTP 结合）状态之间的构象转换周期。激活和失活受到 GDP/GTP 交换因子 (GEF) 和 GTP 酶激活蛋白 (GAP) 的严格控制，它们加速了本质上缓慢的核苷酸交换和 GTP 水解速率。活性 Rab GTP 酶与参与膜运输各个阶段的多种效应子相互作用。活性 Rab GTP 酶的功能输出通过具有多个 Rab 结合位点的多价效应器进行整合。活性 Rab GTP 酶还为下游或上游 Rab GTP 酶招募 GEF 或 GAP，以协调连续的运输阶段并促进膜成熟。该提案的总体目标是了解 Rab GEF 和 GAP 的膜招募、招募后 Rab GTPases 的选择性激活和失活以及微生物病原体对这些宿主过程的操纵的结构和分子基础。具体来说，我们将晶体学、突变和基于细胞的分析与定量 Rab 家族识别图谱相结合，以研究以下结构和分子基础：（目标 1）DENN 和 Vps9 结构域 GEF 的招募和 Rab 识别/激活； （目标 2）TBC 域 GAP 的招募和 Rab 识别/激活； （目标 3）嗜肺军团菌操纵宿主 Rab GTPases。这些目标的成功完成将为在正常和致病条件下支撑 Rab GTPase 调节膜生物学的尚未明确的分子相互作用网络和结构机制提供新的见解。