p66Shc Signaling Functions in Cardiomyocytes

p66Shc 心肌细胞中的信号传导功能

• 批准号: 8235812
• 负责人: Susan F Steinberg
• 金额: $ 39.85万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-15 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8235812
• 关键词: Ablation; Adrenergic Receptor; Animal Model; Antioxidants; Apoptosis; Apoptotic; Attention; Awareness; Binding; Biochemical; Cardiac; Cardiac Myocytes; Cardiomyopathies; Cardiovascular Diseases; Cardiovascular system; Caveolae; Cell Death; Cells; Data; Deterioration; Development; Etiology; Event; Evolution; Failure; Functional disorder; Gene Expression; Gene Silencing; Generations; Genes; Genetic; Goals; Growth; Heart; Heart Diseases; Heart Hypertrophy; Heart failure; Hypertrophy; Knock-out; Lead; Link; Longevity; Measurable; Mitochondria; Modeling; Modification; Molecular; Mus; Natural History; Oxidation-Reduction; Oxidative Stress; Pathogenesis; Pathway interactions; Phenotype; Phosphorylation; Predisposition; Production; Property; Protein Isoforms; Protein Kinase C; Proteins; Proto-Oncogene Proteins c-akt; RNA Interference; Reactive Oxygen Species; Regulation; Regulatory Pathway; Relative (related person); Role; Signal Transduction; Small Interfering RNA; Stimulus; Testing; Therapeutic; adapter protein; adenoviral-mediated; aging gene; base; biological adaptation to stress; diabetic; in vivo; novel; novel therapeutics; overexpression; p66(ShcA) protein; prevent; protein structure; public health relevance; receptor; response

DESCRIPTION (provided by applicant): p66Shc has recently emerged as a master regulator of reactive oxygen species (ROS) production and cardiovascular oxidative stress responses. While a role for p66Shc as an 'aging' gene that amplifies ROS generation in mitochondria and leads to measurable changes in lifespan in animal models is convincing, there is almost no information on p66Shc functions in cardiomyocytes. Preliminary studies in this application implicate p66Shc as a target of an adrenergic receptor pathway involving ROS and PKC that is localized to caveolae and regulates AKT-FOXO3a phosphorylation and anti-oxidant gene expression. We identify an effect of the G1q-dependent hypertrophy pathway to increase p66Shc expression and target p66Shc to mitochondria where it is predicted to increase ROS generation. We identify a role for protein kinase C-4 (PKC4) and PKC5 to influence p66Shc phosphorylation and localization. p66Shc regulation by PKC4 is particularly noteworthy, as PKC4 also participates in mitochondrial events that control ROS accumulation and apoptosis. Studies in this application will consider the role of p66Shc as a G1q-induced gene product that cooperates with PKC to influence the evolution of cardiac failure phenotypes. Specific aim I will identify p66Shc activation mechanisms and p66Shc signaling functions in cardiomyocytes. The goal is to determine whether p66Shc participates in ROS-regulatory signaling mechanisms in caveolae and mitochondria that influence growth and/or apoptosis. Most studies do not resolve the signaling functions of p66Shc versus the smaller p46/p52Shc isoforms (that do not regulate Redox signaling). Studies in Specific Aim II will use p66Shc knockout models, siRNA gene silencing, and adenoviral mediated overexpression strategies to resolve the specific functions of p66Shc (and critical determinants within the p66Shc protein structure) in mechanisms that regulate ROS production and cardiomyocyte growth/apoptosis. Studies in Specific Aim III will focus on the role of PKC4 to cooperate with p66Shc to control cardiomyocyte remodeling. These studies are based upon preliminary data showing that PKC4 is a p66Shc binding partner that influences p66Shc-S36 phosphorylation and p66Shc subcellular targeting. Finally, studies in Specific Aim IV will examine whether p66Shc gene silencing prevents the structural remodeling and functional deterioration that develops in selected models of cardiac hypertrophy/failure. Evidence that p66Shc contributes to the etiology and/or pathogenesis of cardiac dysfunction would provide the basis for future research focusing on p66Shc as an 'aging gene' that influences the evolution of cardiovascular disorders associated with oxidative stress (ischemic, diabetic, atherosclerotic, hypertensive, and hypertrophic heart disease). The long-term goal of such studies would be to develop novel therapeutic strategies that prevent p66Shc expression or interdict p66Shc function that afford cardioprotection. PUBLIC HEALTH RELEVANCE: Studies in this application focus on p66Shc, an adapter protein that acts as a master regulator of oxidative stress responses and life span in animal models. Based upon the growing awareness that oxidative stress contributes to the evolution of ischemic, diabetic, hypertensive, and/or atherosclerotic heart diseases (i.e., oxidative stress is important regardless of etiology) and our recent studies showing that cardiac hypertrophy leads to increased p66Shc expression and enhanced p66Shc function in cardiomyocytes, studies in this application will examine the role of p66Shc-dependent Redox-regulatory mechanisms in cardiomyocyte growth and apoptosis responses. The long-term goal is to expose novel molecular strategies that can be used to reduce p66Shc expression and/or interdict p66Shc actions to prevent or slow the natural history of clinically important cardiovascular disorders.

描述（由申请人提供）：p66 Shc最近已成为活性氧（ROS）产生和心血管氧化应激反应的主要调节因子。虽然p66 Shc作为一种“衰老”基因的作用是令人信服的，它放大了线粒体中ROS的产生，并导致动物模型中寿命的可测量变化，但几乎没有关于p66 Shc在心肌细胞中功能的信息。本申请的初步研究表明，p66 Shc是肾上腺素能受体途径的靶标，该途径涉及ROS和PKC，其定位于小窝并调节AKT-FOXO 3a磷酸化和抗氧化剂基因表达。我们确定了G1 q依赖性肥大途径增加p66 Shc表达的作用，并将p66 Shc靶向线粒体，预计在线粒体中增加ROS的产生。我们确定了蛋白激酶C-4（PKC 4）和PKC 5的作用，影响p66 Shc磷酸化和定位。PKC 4对p66 Shc的调节尤其值得注意，因为PKC 4也参与控制ROS积累和凋亡的线粒体事件。本申请中的研究将考虑p66 Shc作为G1 q诱导的基因产物与PKC合作影响心力衰竭表型的演变的作用。具体目的我将确定p66 Shc激活机制和p66 Shc信号转导功能在心肌细胞。目的是确定p66 Shc是否参与影响生长和/或凋亡的小窝和线粒体中的ROS调节信号机制。大多数研究没有解决p66 Shc与较小的p46/p52 Shc亚型（不调节氧化还原信号传导）的信号传导功能。特定目标II的研究将使用p66 Shc敲除模型，siRNA基因沉默和腺病毒介导的过表达策略来解决p66 Shc（和p66 Shc蛋白结构中的关键决定因素）在调节ROS产生和心肌细胞生长/凋亡机制中的特定功能。Specific Aim III的研究将重点关注PKC 4与p66 Shc合作控制心肌细胞重塑的作用。这些研究是基于初步数据显示，PKC 4是p66 Shc的结合伴侣，影响p66 Shc-S36磷酸化和p66 Shc亚细胞靶向。最后，特定目标IV的研究将检查p66 Shc基因沉默是否可以防止在选定的心脏肥大/衰竭模型中发生的结构重塑和功能恶化。p66 Shc参与心功能不全的病因和/或发病机制的证据将为未来的研究提供基础，重点是p66 Shc作为一种“衰老基因”，影响与氧化应激相关的心血管疾病（缺血性、糖尿病、动脉粥样硬化、高血压和肥厚性心脏病）的演变。这些研究的长期目标是开发新的治疗策略，防止p66 Shc表达或阻断p66 Shc功能，提供心脏保护。 公共卫生相关性：该应用的研究集中在p66 Shc上，这是一种衔接蛋白，在动物模型中作为氧化应激反应和寿命的主要调节剂。基于氧化应激有助于缺血性、糖尿病、高血压和/或动脉粥样硬化性心脏病（即，氧化应激是重要的，与病因学无关），并且我们最近的研究表明心肌肥大导致心肌细胞中p66 Shc表达增加和p66 Shc功能增强，本申请的研究将检查p66 Shc依赖性氧化还原调节机制在心肌细胞生长和凋亡反应中的作用。长期目标是揭示新的分子策略，可用于减少p66 Shc表达和/或阻断p66 Shc作用，以预防或减缓临床重要心血管疾病的自然史。