Regulation of Mutationally Activated Gq/11

突变激活 Gq/11 的调控

基本信息

批准号：
10551862
负责人：
PHILIP B WEDEGAERTNER
金额：
$ 31.2万
依托单位：
THOMAS JEFFERSON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-04-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10551862
关键词：
Address Adult Binding Biochemical Biological Assay Biosensor Blindness Blood capillaries Cardiovascular Physiology Cell Differentiation process Cell membrane Cell model Cell physiology Cells Codon Nucleotides Congenital Hemangioma Cultured Cells Cyclodepsipeptides Cytoplasm Data Disease Endocrine System Diseases Fluorescence Microscopy G-Protein-Coupled Receptors GNAQ gene GTP Binding GTP-Binding Proteins Genes Glutamine Guanine Nucleotide Exchange Factors Guanosine Triphosphate Heart Diseases Heterotrimeric GTP-Binding Proteins Hydrolysis Hypertension Immune Immunofluorescence Microscopy Knowledge Link Location Malignant Neoplasms Mediating Membrane Mitogen-Activated Protein Kinases Modeling Molecular Mutation Mutation Analysis Natural Products Neoplasm Metastasis Neoplasms in Vascular Tissue Neurotransmitters Oncogenic Pathway interactions Patients Phospholipase C Physiological Physiological Processes Plasma Cells Play Protein Subunits Proteins Refractory Regulation Research Project Grants Research Proposals Resistance Role Signal Pathway Signal Transduction Smell Perception Somatic Mutation Sturge-Weber Syndrome Surface Taste Perception Testing Uveal Melanoma Vision Work cell growth regulation cell motility experience extracellular genetic regulatory protein human disease inhibitor live cell microscopy malformation malignant neoplasm of eye mutant nervous system disorder neuron development new therapeutic target novel palmitoylation pharmacologic protein function receptor-mediated signaling reconstitution resistance mechanism response rho therapeutic target trafficking transmission process

项目摘要

Abstract Heterotrimeric G proteins () are well known for their function in linking G protein-coupled receptors (GPCRs) to a variety of intracellular responses, and thereby playing essential roles in transmitting a wide variety of extracellular signals into regulation of countless physiological processes. However, it has also become increasingly recognized that G proteins can function independently of GPCRs. Highlighting the physiological relevance of GPCR-independent G protein function, constitutively activating somatic mutations in several G subunits have been identified and shown to contribute to human disease, most prominently in cancer. This research project focuses on constitutively active mutants of the highly similar q and 11 subunits, collectively termed q/11. Mutations at one of two hotspot residues, that result in inhibition of the GTP hydrolysis turn-off mechanism, can convert q/11 into an oncogenic driver of uveal melanoma, and such constitutively activating q/11 mutations have also been associated with vascular tumors, capillary malformation, congenital hemangioma and Sturge Weber syndrome. This research project will focus on uncovering basic cellular mechanisms regulating signaling by mutationally activated q/11. G subunits are typically thought as exceptionally difficult proteins for which to develop pharmacological or molecular inhibitors. However, numerous recent studies have demonstrated that the highly similar natural products YM-254890 and FR900359 are effective inhibitors of wild type and mutationally activated q/11. Our work has uncovered an unexpected mechanism of action of these inhibitors leading to the hypothesis that YM- 254890 and FR900359 inhibit q/11, at least in part, by regulating subcellular localization of q/11. Understanding the novel mechanisms of inhibition and cellular regulation of mutationally activated q/11 may suggest novel therapeutic targets or approaches for disrupting dysregulated signaling. The objectives in this research project will be pursued by a variety of experimental approaches, including using cultured cells, immunofluorescence microscopy, fluorescence microscopy of live cells, constitutive targeting to specific subcellular locations, biosensors, pharmacological inhibitors, mutational analysis, and biochemical assays.

抽象的异三聚体 G 蛋白 () 以其连接 G 蛋白偶联受体的功能而闻名（GPCR）对多种细胞内反应，从而在广泛的传播中发挥重要作用然而，它也有多种细胞外信号调节无数的生理过程。人们越来越认识到 G 蛋白可以独立于 GPCR 发挥作用。独立于 GPCR 的 G 蛋白功能的生理相关性，组成性激活体细胞突变多个 G 亚基中的基因已被鉴定并被证明会导致人类疾病，其中最突出的是该研究项目重点关注高度相似的 αq 和 α11 的组成型活性突变体。亚基，统称为 q/11 两个热点残基之一的突变，导致抑制 GTP 水解关闭机制，可以将 q/11 转化为葡萄膜黑色素瘤的致癌驱动因素，并且这种组成性激活的 q/11 突变也与血管瘤、毛细血管瘤有关。该研究项目将重点关注畸形、先天性血管瘤和斯特奇韦伯综合征。揭示通过突变激活的 αq/11 调节信号传导的基本细胞机制。通常被认为是极其难以开发药理学或分子生物学的蛋白质然而，最近的大量研究表明，天然产物高度相似。 YM-254890 和 FR900359 是野生型和突变激活的 αq/11 的有效抑制剂。发现了这些抑制剂的一种意想不到的作用机制，导致了这样的假设：YM- 254890 和 FR900359 至少部分通过调节 αq/11 的亚细胞定位来抑制 αq/11。了解突变激活的 q/11 的抑制和细胞调节的新机制可能提出了破坏失调信号传导的新治疗靶点或方法。研究项目将通过各种实验方法进行，包括使用培养细胞，免疫荧光显微镜、活细胞荧光显微镜、特定特异性的组成型靶向亚细胞定位、生物传感器、药理学抑制剂、突变分析和生化测定。