Mechanisms of cAMP Compartmentation

cAMP 区室的机制

• 批准号: 8733710
• 负责人: ROBERT D HARVEY
• 金额: $ 27.66万
• 依托单位: UNIVERSITY OF NEVADA RENO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8733710
• 关键词: Address; Adrenergic Agents; Adrenergic Receptor; Adult; Affect; Behavior; Biological Models; Biosensor; Buffers; Cardiac Myocytes; Cell membrane; Cells; Cellular Structures; Cholesterol; Complex; Computer Simulation; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cytoplasmic Tail; Cytoskeleton; Data; Diffusion; Disease; Fluorescence Resonance Energy Transfer; Goals; Hormones; Kinetics; Lead; Life; Measurement; Measures; Mechanics; Mediating; Membrane; Metabolic; Methods; Mitochondria; Modeling; Monitor; Muscarinic M2 Receptor; Muscarinics; Muscle Cells; Neurotransmitters; Physiological; Play; Prevention strategy; Problem Solving; Process; Production; Prostaglandin Receptor; Publishing; Rattus; Receptor Activation; Receptor Signaling; Regulation; Role; Sarcoplasmic Reticulum; Second Messenger Systems; Signal Pathway; Signal Transduction; Signaling Molecule; Signaling Protein; Subcellular structure; System; Systems Biology; Testing; Ventricular; adrenergic; base; beta-adrenergic receptor; cell type; innovation; novel strategies; phosphoric diester hydrolase; receptor; receptor-mediated signaling; research study; response; second messenger

DESCRIPTION (provided by applicant): The second messenger cAMP is involved in regulating a variety of responses in virtually every cell in our bodies. One example is the cardiac myocyte, where beta-adrenergic receptors mediate sympathetic effects on electrical, mechanical, and metabolic activity through the production of cAMP. However, there are actually multiple receptors capable of regulating cAMP production in cardiac myocytes, just like many other cells. Even though various receptors may share this common second messenger, they do not all elicit the same functional responses. The common explanation is that cAMP production is compartmentalized, spatially limiting the extent of responses produced by certain receptors. The idea that activation of a receptor does not lead to uniform stimulation or inhibition of cAMP production throughout the cell might seem intuitively obvious, yet it is not fully understood how this is achieved. The common assumption is that phosphodiesterases act as functional barriers to diffusion, creating discrete cAMP signaling domains. We will test the hypothesis that phosphodiesterase activity plays an important role in compartmentation, but not as a barrier to diffusion. We will also test the hypothesis that the cytoskeleton and cholesterol-dependent organization of the plasma membrane play essential roles in this process. The strength of this application lies in the innovative combination of methods that will be used to address these hypotheses. We will employ a systems biology approach that involves the use of multiple fluorescence resonance energy transfer (FRET) based biosensors to monitor cAMP activity in distinct subcellular compartments of live cells, together with quantitative computational modeling of compartmentalized cAMP signaling. The production of cAMP is an important means of eliciting beneficial changes in function of many cell types. However, cAMP-dependent signaling can also produce pathological responses under the right (or wrong) conditions. It has been hypothesized that the difference between the physiological and pathological effects may be a function of appropriate compartmentation of cAMP signaling. Therefore, understanding the contribution of factors that are responsible for coordinating the spatial and temporal distribution of cAMP at the subcellular level could be important for developing new strategies for the prevention or treatment of unfavorable responses associated with many different disease states.

描述（由申请人提供）：第二信使 cAMP 参与调节我们体内几乎每个细胞的多种反应。心肌细胞就是一个例子，其中 β-肾上腺素能受体通过产生 cAMP 介导对电、机械和代谢活动的交感神经作用。然而，就像许多其他细胞一样，实际上有多种受体能够调节心肌细胞中 cAMP 的产生。尽管各种受体可能共享这个共同的第二信使，但它们并不都引起相同的功能反应。常见的解释是 cAMP 的产生是分开的，在空间上限制了某些受体产生的反应程度。受体的激活不会导致整个细胞内 cAMP 产生的均匀刺激或抑制，这一想法在直观上似乎是显而易见的，但尚不完全理解这是如何实现的。普遍的假设是磷酸二酯酶充当扩散的功能屏障，产生离散的 cAMP 信号传导域。我们将检验这样的假设：磷酸二酯酶活性在区室化中发挥重要作用，但不是扩散的障碍。我们还将验证细胞骨架和质膜的胆固醇依赖性组织在此过程中发挥重要作用的假设。该应用程序的优势在于将用于解决这些假设的方法的创新组合。我们将采用系统生物学方法，涉及使用基于多个荧光共振能量转移（FRET）的生物传感器来监测活细胞不同亚细胞区室中的 cAMP 活性，以及​​区室化 cAMP 信号传导的定量计算模型。 cAMP 的产生是引发多种细胞类型功能有益变化的重要手段。然而，cAMP 依赖性信号传导在正确（或错误）条件下也可以产生病理反应。据推测，生理效应和病理效应之间的差异可能是 cAMP 信号传导适当划分的函数。因此，了解在亚细胞水平上协调 cAMP 空间和时间分布的因素的贡献对于制定预防或治疗与许多不同疾病状态相关的不利反应的新策略非常重要。