Neuronal control of body weight and size by the Gbeta5-R7 signaling complex

Gbeta5-R7 信号复合物对体重和体型的神经元控制

基本信息

批准号：
10001791
负责人：
Vladlen Z Slepak
金额：
$ 19.19万
依托单位：
UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-09-15 至 2020-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10001791
关键词：
Ablation Acute Adult Affect Agonist Alleles Animals Antibodies Behavior Beta Cell Biochemical Biological Assay Biophysics Body Size Body Weight Brain CRISPR/Cas technology Cardiovascular Diseases Cardiovascular system Cell Line Cell Nucleus Cells Comorbidity Complex Control Animal Data Diabetes Mellitus Diagnostic Disease Energy Intake Engineering Etiology Event Family G Protein-Coupled Receptor Signaling G-Protein-Coupled Receptors GNB5 gene GTP-Binding Protein Regulators GTP-Binding Protein beta Subunits GTP-Binding Proteins Gene Transfer Genes Genetic Goals Growth Health Hormone secretion Hormones Human Human Genetics Hypothalamic Hormones Hypothalamic structure Image Analysis In Situ In Vitro Injections Insulin Investigation Kidney Diseases Knock-out Lead Link LoxP-flanked allele Malignant Neoplasms Measurement Mediating Messenger RNA Metabolic Diseases Metabolic syndrome Metabolism Methods Microscopic Molecular Mus Muscarinic Acetylcholine Receptor Mutation Neuraxis Neuroendocrinology Neuroglia Neurologic Neurons Neurosciences Neurosecretion Neurosecretory Systems Neurotransmitters Non-Insulin-Dependent Diabetes Mellitus Obesity Organ Pancreas Pathologic Pathway interactions Pattern Peripheral Pharmacology Phenotype Phosphorylation Physiological Play Population Proteins RGS Proteins Regulation Reproduction Research Risk Factors Role Second Messenger Systems Serum Signal Transduction Signaling Protein Slice Stimulus Stroke Structure Structure of beta Cell of islet System Technology Testing Therapeutic Tissues United States Viral Viral Vector Virus Weight Gain base cholinergic design dimer effective therapy experimental study hormonal signals hormone regulation improved in vivo insight insulin secretion kinase inhibitor knock-down knockout gene mutant nervous system disorder novel overexpression promoter protein complex protein function protein protein interaction real-time images

项目摘要

Abstract Obesity is a major co-morbidity factor in diabetes, cancer, cardiovascular, neurological and other diseases. One group of genes recently linked to obesity in humans are genes encoding the R7 family of regulator of G protein signaling proteins (RGS6, 7, 9 and 11) and Gnb5, which encodes the G protein beta subunit G5. G5 and R7 proteins form obligatory dimers, so that the Gnb5 knockout causes complete degradation of the entire G5-R7 complex. This proposal studies how a deficiency in the Gnb5 and R7 genes can lead to obesity; the ultimate goal is to discover effective treatments of disorders associated with neuroendocrine pathways regulated by these genes. The proposed research plan builds upon earlier discoveries that together constitute a strong premise for this study. Ablation of one Gnb5 allele leads to obesity and metabolic syndrome in mice; this finding was later confirmed by human genetics. Subsequent mechanistic investigations in this lab identified a novel role for the G5-R7 complex in pancreatic beta cells where G5-R7 strongly promoted insulin secretion. Brain is the main organ regulating body weight, and the expression level of G5-R7 is much higher than in the pancreas or any other peripheral tissues. These considerations lead to the hypothesis that G5-RGS7 regulates body weight via its function in the CNS, where as in the insulin-secreting beta cells, G5-R7 can regulate hormone and/or neurotransmitter secretion by neurons. In support of this hypothesis, recent studies in the lab demonstrated that local knockout of Gnb5 in the hypothalamus using LoxP/Cre technology caused a dramatic increase of body weight and adiposity in adult mice. The proposed research will develop this discovery. Specific Aim 1 will analyze the effects of Gnb5 ablation in specific hypothalamic nuclei and types of neurons on body weight and levels of various hormones. Overexpression of Gnb5 using viral-mediated gene transfer will be performed to rescue obesity. Aim 2 will determine which hormones and signaling proteins (i.e., GPCRs) are co-expressed with Gnb5 in hypothalamic neurons. Tissue and acutely cultured neurons will be examined for secretion of specific hormones and signaling. Specific Aim 3 will study molecular events affected by G5-R7 via its knockout (CRISPR/Cas9), knockdown and overexpression in cell lines that endogenously express M3R and G5-R7. Experiments will focus on signaling, structure-function analysis of G5-R7 and signal-stimulated secretion utilizing pharmacological agents and biochemical and biophysical assays. Through unraveling a novel mechanism that regulates neuronal functions, this project may have a strong impact on understanding etiology of obesity and other neuroendocrine disorders.

抽象的肥胖是糖尿病，癌症，心血管，神经和其他的主要合并症疾病。最近与人类肥胖有关的一组基因是编码R7家族的基因 G蛋白信号蛋白（RGS6、7、9和11）和GNB5的调节剂，该蛋白编码G蛋白β 亚基G5。 G5和R7蛋白会形成强制性二聚体，因此GNB5敲除使完整整个G5-R7复合物的降解。该建议研究GNB5和R7基因的缺乏会导致肥胖；最终目标是发现与这些基因调节的神经内分泌途径。拟议的研究计划建立在较早的发现，共同构成了一个强大的前提对于这项研究。一个GNB5等位基因的消融导致小鼠的肥胖和代谢综合征。这个发现是后来被人类遗传学证实。该实验室的随后的机械调查确定了胰腺β细胞中G5-R7强烈促进胰岛素分泌的G5-R7复合物。大脑是控制体重的主要器官，G5-R7的表达水平比胰腺或任何其他外围组织。这些考虑因素导致了G5-RGS7调节身体的假设通过其在中枢神经系统中的功能，重量通过在胰岛素分泌β细胞中，G5-R7可以调节骑马和/或神经递质分泌神经元。为了支持这一假设，实验室的最新研究证明了使用LOXP/CRE技术在下丘脑中局部淘汰GNB5引起了戏剧性成年小鼠体重和肥胖的增加。拟议的研究将发展这一发现。特定的目标1将分析GNB5消融在特定下丘脑核和神经元类型上的影响体重和各种恐怖的水平。使用病毒介导的基因转移对GNB5的过表达将进行拯救肥胖。 AIM 2将确定哪些骑兵和信号蛋白（即GPCR）为在下丘脑神经元中与GNB5共表达。将检查组织和急性培养的神经元的特定恐怖和信号传导的分泌。特定目标3将研究受G5-R7影响的分子事件通过其敲除（CRISPR/CAS9），内源表达M3R的细胞系中的敲低和过表达和g5-r7。实验将集中于信号传导，G5-R7的结构 - 功能分析和信号刺激使用药物剂以及生化和生物物理测定法的分泌。通过解开调节神经元功能的新型机制，该项目可能对理解有很大的影响肥胖和其他神经内分泌疾病的病因。