p66Shc Signaling Functions in Cardiomyocytes

p66Shc 心肌细胞中的信号传导功能

• 批准号: 7888711
• 负责人: Susan F Steinberg
• 金额: $ 40.21万
• 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/7888711
• 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; Future; 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); Research; 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）：p66Shc最近被认为是活性氧（ROS）产生和心血管氧化应激反应的主要调节因子。虽然在动物模型中，p66Shc作为一种“衰老”基因的作用是令人信服的，它可以放大线粒体中ROS的产生，并导致可测量的寿命变化，但几乎没有关于p66Shc在心肌细胞中的功能的信息。本应用的初步研究表明，p66Shc是一个肾上腺素能受体通路的靶点，该通路涉及ROS和PKC，定位于小窝，调节AKT-FOXO3a磷酸化和抗氧化基因表达。我们发现了g1q依赖性肥大通路增加p66Shc表达的作用，并将p66Shc靶向线粒体，预计会增加ROS的产生。我们确定了蛋白激酶C-4 （PKC4）和PKC5影响p66Shc磷酸化和定位的作用。PKC4对p66Shc的调节尤其值得注意，因为PKC4也参与了控制ROS积累和凋亡的线粒体事件。本研究将考虑p66Shc作为g1q诱导的基因产物，与PKC合作影响心力衰竭表型的进化。我将确定p66Shc在心肌细胞中的激活机制和p66Shc信号功能。目的是确定p66Shc是否参与影响生长和/或凋亡的小泡和线粒体中的ros调节信号机制。大多数研究没有解决p66Shc与较小的p46/p52Shc异构体（不调节氧化还原信号）的信号功能。Specific Aim II的研究将使用p66Shc敲除模型、siRNA基因沉默和腺病毒介导的过表达策略来解决p66Shc（以及p66Shc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PKC4协同p66Shc控制心肌细胞重塑的作用。这些研究基于PKC4是影响p66Shc- s36磷酸化和p66Shc亚细胞靶向的p66Shc结合伙伴的初步数据。最后，Specific Aim IV的研究将检验p66Shc基因沉默是否会阻止某些心脏肥厚/衰竭模型中出现的结构重塑和功能恶化。p66Shc参与心功能障碍的病因和/或发病机制的证据将为未来研究p66Shc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）的演变提供基础。这些研究的长期目标是开发新的治疗策略，防止p66Shc表达或阻断p66Shc功能，从而提供心脏保护。