B-arrestin Biased B1- and B2-Adrenergic Receptor Signaling

B-arrestin 偏向 B1- 和 B2- 肾上腺素能受体信号转导

• 批准号: 7919184
• 负责人: Howard A Rockman
• 金额: $ 35.36万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7919184
• 关键词: ADRB1 gene; ADRB2 gene; Adenoviruses; Adopted; Adrenergic Receptor; Adult; Agonist; Apoptosis; Arrestins; Biological Assay; Bioluminescence; Biosensor; Cardiac; Cardiac Myocytes; Catecholamines; Cell Survival; Chronic; Data; Development; Energy Transfer; Engineering; G-Protein-Coupled Receptors; GTP-Binding Proteins; Gene Targeting; Heart; Heart failure; Human; Ischemia; Knock-in Mouse; Lead; Ligands; Mediating; Metabolic; Molecular; Molecular Conformation; Mus; Muscle Cells; Myocardial Infarction; Oryctolagus cuniculus; Pathway interactions; Phenotype; Phosphoproteins; Physiological; Poly(ADP-ribose) Polymerases; Proteins; Proteomics; Receptor Signaling; Recruitment Activity; Reperfusion Therapy; Research Personnel; Role; Signal Pathway; Signal Transduction; Stimulus; Stress; Testing; Therapeutic Agents; Virus; Work; abstracting; arrestin B; arrestin3; desensitization; estin; in vivo; mutant; novel; pressure; protein activation; receptor; response; trafficking

Abstract B-arrestins are multifunctional proteins that are recruited to G protein-coupled receptors (GCPRs) following agonist stimulation. While the classical role of (3-arrestin is to mediate receptor desensitization, work by investigators of this PPG have recently shown that P-arrestin can stimulate signaling in the absence of classical G protein activation. The existence of B-arrestin-mediated signaling independent of G proteins requires that receptors adopt multiple "active" conformations or "ligand selective states". The ability of unique ligand-receptor conformations to promote preferential B-arrestin signaling is an emerging concept known as "biased signaling". The molecular mechanisms that underlie p-an-estin-biased signaling for the p-adrenergic receptor of (PAR), and its physiological consequences in the heart, are not known. In this proposal, we will test the hypothesis that mutant p i - and P2 can be engineered that will selectively stimulate p-arrestinbiased signaling independent of G protein activation, and that p-arrestin-biased signaling will promote cardiomyocyte cell survival to limit the development of heart failure in response to pathological stimuli. Accordingly, the specific aims of the study are: Aim 1: To engineerBp1 AR mutants that show selective bias for p-arrestin recruitment. Aim 2: To identify the mechanism of activation and signaling pathways activated by P1AR and B2AR mutants in the absence of G protein activation. Aim 3: To test in adult cardiomyocytes whether p-arrestin-biasedBP2AR TYY and B1 AR mutants activate cardioprotective signaling in response to agonist stimulation and ischemia. Aim 4: To test in vivo whether the B-arrestin-biased Bp2AR TYY and pi AR mutant activities cardioprotective pathways under conditions of pathological stress. By exploring these aims, we will define the pathways by which G protein-Independent activation of BARs may lead to stimulation of cardioprotective signaling. If our hypothesis is correct, we will show that ligandstimulated PARS, which selectively activate B-arrestin signaling pathways, are cardioprotecitve. Since, by definition, the administration of a ligand that does not stimulate G protein signaling is B-blackade, we will have demonstrated proof-of concept for the development of an entirely novel class of receptor blockers. We believe these data will provide considerable impetus for the development of novel p-arrestin-biased therapeutic agents to treat human heart failure.

摘要 B-抑制蛋白是在激动剂刺激后被募集到G蛋白偶联受体（GCPR）的多功能蛋白质。虽然β-抑制蛋白的经典作用是介导受体脱敏，但该PPG的研究人员最近的工作表明，β-抑制蛋白可以在不存在β-抑制蛋白的情况下刺激信号传导。 经典的G蛋白激活。B-抑制蛋白介导的信号传导独立于G蛋白的存在需要受体采用多种“活性”构象或“配体选择性状态”。独特的能力 促进优先B-抑制蛋白信号传导的配体-受体构象是一个新兴的概念，称为“偏向信号传导”。β-肾上腺素能受体的β-an-estin偏性信号转导的分子机制 （PAR）的受体及其在心脏中的生理后果尚不清楚。在该提议中，我们将测试以下假设：突变体P1和P2可以被工程化，其将选择性地刺激不依赖于G蛋白活化的β-抑制蛋白偏向性信号传导，并且β-抑制蛋白偏向性信号传导将促进心肌细胞存活以限制响应于病理刺激的心力衰竭的发展。因此，研究的具体目标是： 目的1：构建对β-arrestin募集有选择性偏好的Bp 1 AR突变体。 目的2：确定激活机制 以及在没有G蛋白激活的情况下由P1 AR和B2 AR突变体激活的信号通路。 目标3：在成年心肌细胞中测试p-抑制蛋白偏置的BP 2AR TYY和B1 AR突变体是否响应激动剂刺激和缺血激活心脏保护信号。 目标4：为了在体内测试B-抑制蛋白偏向的Bp 2AR TYY和P1 AR突变体在病理应激条件下是否具有心脏保护途径的活性。 通过探索这些目标，我们将确定的途径，G蛋白不依赖激活的BAR可能导致刺激的心脏保护信号。如果我们的假设是正确的，我们将表明， PARS选择性激活B-抑制蛋白信号通路，具有心脏保护作用。由于根据定义，不刺激G蛋白信号传导的配体的施用是B-黑色素，因此我们将证明开发全新类别的受体阻断剂的概念验证。我们相信，这些数据将提供相当大的推动力的发展，新的p-抑制蛋白偏向治疗药物，以治疗人类心力衰竭。