Spatial Regulation of RGS and G Protein Signaling

RGS 和 G 蛋白信号传导的空间调控

• 批准号: 8067857
• 负责人: MARILYN Gist FARQUHAR
• 金额: $ 54.26万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-17 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8067857
• 关键词: Abbreviations; Actins; Adrenergic Receptor; Affect; Apoptosis; Binding; Binding Proteins; Biological Assay; Biosensor; Cell Proliferation; Cell membrane; Cell physiology; Cells; Chemotaxis; Clathrin; Coupling; Cyclic AMP-Dependent Protein Kinases; Cytoskeleton; Development; Disease; Down-Regulation; Dynamin; EGF gene; Early Endosome; Electron Microscopy; Endocytosis; Endoplasmic Reticulum; Endosomes; Enzymes; Epidermal Growth Factor Receptor; Epithelial; Fluorescence Resonance Energy Transfer; G Protein-Coupled Receptor Genes; G-Protein Signaling Pathway; G-Protein-Coupled Receptors; G-substrate; GTP-Binding Protein Regulators; GTP-Binding Proteins; GTPase-Activating Proteins; Goals; Golgi Apparatus; Grant; Growth; Growth Factor Receptors; Guanine Nucleotide Dissociation Inhibitors; Guanine Nucleotide Exchange Factors; Guanosine Triphosphate; Guanosine Triphosphate Phosphohydrolases; Image; Immunofluorescence Immunologic; Insulin; Kinetics; Life; Light; Link; Location; MAP Kinase Gene; MAPK3 gene; Malignant Neoplasms; Mannosidase; Mass Spectrum Analysis; Mediating; Membrane Microdomains; Metabolism; Mitochondria; Mitogen-Activated Protein Kinases; Modeling; Molecular; Multivesicular Body; Neoplasm Metastasis; Normal Cell; Pathway interactions; Phosphatidylinositols; Phosphorylation; Phosphotransferases; Play; Polypyrimidine Tract-Binding Protein; Protein C; Protein Tyrosine Phosphatase; Proteins; RGS Domain; RGS Proteins; RGS19 gene; Receptor Signaling; Regulation; Respiration; Role; Signal Pathway; Signal Transduction; Site; Sorting - Cell Movement; Stimulus; Structural Models; System; Tyrosine Phosphorylation Site; Vesicle; Work; anticancer research; antitumor agent; base; cancer cell; cell behavior; cell motility; cellular imaging; in vivo; insight; macrophage; neoplastic cell; novel; paraform; phosphatidylinositol 3-phosphate; phosphatidylinositol 4-phosphate; protein function; public health relevance; receptor downregulation; research study; trafficking

DESCRIPTION (provided by applicant): During the last 5-7 years, we identified several new proteins that are components of novel G protein signaling pathways. The characterization of these proteins has brought to light new roles for trimeric G proteins in cell proliferation, cell migration, and mitochondrial dynamics. Our accomplishments during the last 5 years of this grant include: 1) Discovery of a novel regulatory role for G1s in EGF receptor (EGFR) downregulation and signaling; 2) Demonstration of the crucial role played by GIPC in TrkA NGF signaling and MAPK activation; 3) Identification of GIV, a novel G1 binding protein, and demonstration that activation of G1i3 and its interaction with GIV is essential for cell migration and Akt activation during cell migration; 4) Discovery of hNOA1 (formerly called MIG78), a new dynamin-like GTPase which may provide a link between mitochondrial dynamics, respiration and apoptosis; 5) Identification of MIR16 (GDE1), a novel enzyme that provides a putative link between phosphoinositide metabolism and G protein signaling; and 6) Discovery of a new paradigm for spatial regulation of G1i signaling in clathrin-coated membrane microdomains. The overall goal of the work proposed is to further define two of these novel pathways we have discovered-namely, the role of G1i3 and GIV in cell migration and Akt signaling and the role of G1s in regulation of EGFR trafficking and signaling. We will focus on three specific aims: Specific Aim #1: To assess the functional interaction between G1i3 and GIV during cell migration. Our working model is that GIV serves as a non-receptor GEF and is the trigger that activates the signaling cascade culminating in efficient cell motility. Specific Aim #2: To investigate the spatial and temporal regulation of G1i3 and GIV's interaction and translocation from the Golgi to the PM in migrating cells. We will investigate where they interact and where G1i3 is activated using fluorescent biosensors, FRET and FRAP in living cells. Specific Aim #3: To pinpoint the mechanisms by which G1s and RGS-PX1 affect EGF receptor signaling, trafficking and sorting for degradation. We will investigate their effects on phosphorylation of EGFR, recruitment of adaptors, and downstream signaling as well as trafficking through the endosomal system, and sorting for down-regulation. These studies can be expected to provide insights into how normal cells function and the molecular basis for dysregulation of cell proliferation and migration associated with metastasis that occurs in cancer cells. Due to their crucial functions in regulating cell behavior these new molecules represent attractive targets for development of pharmacologic and anti-tumor agents. PUBLIC HEALTH RELEVANCE: Under this grant we have discovered and characterized a number of new molecules that are part of novel G protein signaling networks which regulate many cell processes important in cancer research including endocytosis, growth and proliferation, cell migration and metastasis. The studies planned in this application can be expected to shed light on new G protein functions in normal cells as well as to provide key insights into the molecular basis of the dysregulation of cell proliferation and migration that occur in cancer and other diseases. Due to their crucial functions in cell regulation these new molecules represent attractive targets for development of pharmacologic and anti-tumor agents.

描述（由申请人提供）：在过去的5-7年里，我们发现了一些新的蛋白质，它们是新的G蛋白信号通路的组成部分。这些蛋白的特性揭示了三聚体G蛋白在细胞增殖、细胞迁移和线粒体动力学中的新作用。在过去5年的资助中，我们的成就包括：1)发现G1s在EGF受体（EGFR）下调和信号传导中的新调控作用；2) GIPC在TrkA NGF信号通路和MAPK激活中的重要作用；3)鉴定G1结合蛋白GIV，并证明G1i3的激活及其与GIV的相互作用对细胞迁移和细胞迁移过程中Akt的激活至关重要；4)发现hNOA1（以前称为MIG78），这是一种新的类似动力蛋白的GTPase，可能在线粒体动力学、呼吸和凋亡之间提供联系；5)鉴定MIR16 (GDE1)，这是一种新的酶，可能在磷酸肌苷代谢和G蛋白信号传导之间提供联系；6)发现了网格蛋白包覆膜微域中G1i信号空间调控的新范式。这项工作的总体目标是进一步定义我们发现的两种新途径，即G1i3和GIV在细胞迁移和Akt信号传导中的作用，以及G1s在调节EGFR运输和信号传导中的作用。我们将专注于三个特定目标：特定目标#1：评估细胞迁移过程中G1i3和GIV之间的功能相互作用。我们的工作模型是，GIV作为非受体GEF，是激活信号级联的触发器，最终达到有效的细胞运动。具体目的2：研究迁移细胞中G1i3和GIV相互作用和从高尔基体到PM转运的时空调控。我们将在活细胞中使用荧光生物传感器、FRET和FRAP来研究它们相互作用的位置以及G1i3被激活的位置。具体目标#3：查明G1s和RGS-PX1影响EGF受体信号传导、运输和降解分类的机制。我们将研究它们对EGFR磷酸化、接头募集、下游信号以及内体系统运输的影响，并对下调进行分类。这些研究有望深入了解正常细胞的功能以及与癌细胞转移相关的细胞增殖和迁移失调的分子基础。由于它们在调节细胞行为方面的重要功能，这些新分子是开发药物和抗肿瘤药物的有吸引力的靶点。