Characterization of mammalian COG complex-interacting Golgi trafficking machinery

哺乳动物 COG 复杂相互作用的高尔基体运输机制的表征

• 批准号: 9768870
• 负责人: VLADIMIR V LUPASHIN
• 金额: $ 11.23万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9768870
• 关键词: Alzheimer' s Disease; Architecture; Back; Binding; Binding Sites; Biochemical; Biological Assay; Capsid Proteins; Cell Maintenance; Cell membrane; Cell physiology; Cells; Cellular Membrane; Coat Protein Complex I; Complex; Congenital Disorders; Cystic Fibrosis; Data; Defect; Diabetes Mellitus; Docking; Enzymes; Epitopes; Eukaryotic Cell; Family; Golgi Apparatus; Hermanski-Pudlak Syndrome; Human; Intracellular Membranes; Lobe; Maintenance; Malignant Neoplasms; Maps; Membrane; Microscopy; Mitochondria; Mutation; Organism; Population; Post-Translational Protein Processing; Protein Glycosylation; Protein Secretion; Proteins; Recycling; Role; SNAP receptor; Series; Signal Transduction; Structure; Testing; Thinking; Vesicle; Work; beta-COP; comparative; flexibility; gene product; glycosylation; high throughput screening; human disease; insight; lipid biosynthesis; mitochondrial membrane; polarized cell; protein protein interaction; protein transport; retinal rods; snRNP Structural Core Protein; trafficking; virtual

ABSTRACT In all eukaryotic cells intracellular membrane trafficking is critical for a range of important cellular functions including protein secretion, post-translational modifications, cell signaling, cell polarization, and cell maintenance. Defects in membrane trafficking can underline, or even exacerbate, a number of human diseases including cancer, diabetes mellitus, Alzheimer’s, cystic fibrosis, Hermansky-Pudlak syndrome and Congenital Disorders of Glycosylation. We have pioneered the functional analysis of the Conserved Oligomeric Golgi (COG), an evolutionarily conserved complex of eight gene products, each of which is critical for the membrane trafficking in the Golgi apparatus. The COG complex interacts with SNAREs, SM proteins, Rabs, coiled-coil tethers and COPI coat to organize specific docking and fusion of transport intermediates with their acceptor membrane. At least half, but probably all COG subunits consist largely of helical bundles stacked in series to form long flexible rods. This architectural feature is also found in three related tethering complexes Dsl/ZW10, GARP and exocyst that act to tether vesicles to ER, TGN and plasma membrane, suggesting a common underlying tethering mechanism. This proposal seeks to probe in greater detail the mechanism by which the COG complex orchestrates trafficking in the Golgi complex. 1. We will test the hypothesis that membrane bound COG subunits are arranged in several combinations including Lobe A, Lobe B and Lobe A/B complexes that are spatially separated and likely to participate in different membrane trafficking steps. 2. We will test the hypothesis that the COG4 and COG8 proteins can initiate the formation of two different tethering platforms which attract two populations of Golgi trafficking intermediates. 3. We will test the hypothesis that the interactions between COG subunits and their protein partners are necessary to maintain the COG complexes function of tethering retrograde vesicles recycling Golgi enzymes and retrograde cargo. 4. We will use biochemical and microscopy approaches to investigate cross-talk between the COG complex and other CATCHR complexes specifically focusing on the cross-talk between Lobe B of the COG complex and the GARP complex, both of which are required for the assembly of trans-Golgi SNARE complex.

摘要 在所有真核细胞中，细胞内膜运输对于一系列重要的细胞功能是至关重要的 包括蛋白质分泌、翻译后修饰、细胞信号传导、细胞极化和细胞凋亡。 上维护膜运输的缺陷可以强调，甚至加剧，许多人类疾病。 疾病，包括癌症、糖尿病、阿尔茨海默病、囊性纤维化、Hermansky-Pudlak综合征和 先天性糖基化障碍。我们开创了保守寡聚体的功能分析， 高尔基体（COG），一种进化上保守的8个基因产物的复合体，其中每一个都是关键的， 高尔基体中的膜运输。COG复合物与SNARE、SM蛋白、Rab 卷曲螺旋系链和COPI涂层，以组织转运中间体与其 受体膜至少有一半，但可能所有的COG亚基主要由螺旋束堆叠在一起组成。 系列以形成长的柔性杆。这一建筑特征在三个相关的系留复合体中也有发现 Dsl/ZW 10、GARP和外囊，其作用是将囊泡拴系到ER、TGN和质膜上，这表明 共同的底层网络共享机制。这项建议旨在更详细地探讨机制， COG复合体协调了高尔基复合体的贩运。 1.我们将检验膜结合COG亚基以几种组合排列的假设 包括叶A、叶B和叶A/B复合体，它们在空间上分离，并可能参与 不同的膜运输步骤。 2.我们将测试这样的假设，即COG 4和COG 8蛋白可以启动两种不同的蛋白质的形成。 拴系平台吸引两个群体的高尔基体贩运中间。 3.我们将检验这样的假设，即COG亚基与它们的蛋白质伴侣之间的相互作用是 维持COG复合物的束缚逆行囊泡回收高尔基体酶的功能所必需的 和逆行货物。 4.我们将使用生物化学和显微镜方法来研究COG复合物之间的串扰 以及其它专门关注COG复合体的波瓣B之间的串扰的CATALYST复合体 和GARP复合体，这两者都是组装trans-Golgi SNARE复合体所必需的。