Mechano-Chemical Regulation of GPCR/PKA Signaling During Cell Migration

细胞迁移过程中 GPCR/PKA 信号传导的机械化学调节

• 批准号: 9019564
• 负责人: Alan K Howe
• 金额: $ 35.96万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9019564
• 关键词: Actomyosin; Adenosine; Adenosine A2B Receptor; Cell physiology; Cells; Chemicals; Collection; Couples; Coupling; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Data; Environment; Equilibrium; Event; Extracellular Matrix; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Genetic; Homeostasis; Laboratories; Ligands; Mechanics; Microfluidics; Microscopic; Molecular; Movement; Nature; Pathway interactions; Play; Property; Protein Kinase; Rain; Regulation; Role; Sampling; Shapes; Signal Transduction; Spottings; Stretching; Testing; Walking; base; cell motility; extracellular; inhibitor/antagonist; migration; public health relevance; trafficking

 DESCRIPTION (provided by applicant): Cells maintain a dynamic equilibrium of tension with their microenvironment and this `mechanoreciprocity' controls a wide variety of cellular functions, including cell fate, shape, and movement. Despite this importance, the molecular mechanisms through which cells sense and respond to the mechanical nature of the extracellular matrix are not completely understood. Our laboratory established that the cAMP-dependent protein kinase (PKA) is enriched and activated in the leading edge of cells and that this localization is important for cell migration. In our ongoing efforts to elucidate the mechanis for the spatial regulation of PKA during cell migration, we have recently found that localized PKA activity is regulated by cellular tension. Specifically, leading edge PKA activity is rapidly lost upon inhibition of actomyosin contractility. Moreover, when cells are mechanically stretched, PKA is rapidly and locally activated - in a tension-dependent manner - in the direction of stretch. Finally, inhibition of PKA also blocks durotaxis - cell migration guided by gradients in ECM rigidity and cell-matrix tension. Our current focus is to understand the mechanism that couples cellular tension to localized regulation of PKA. Recent preliminary data establishes that both cellular contractility and localized activation of PKA are dependent on influx of extracellula Ca2+ via the stretch-activated channel TRPM7. Additional data strongly suggest that a G- protein coupled receptor - the A2B adenosine receptor (ADORA2B) - also plays an important role in this mechanism. Based on our observations, we hypothesize that localized activation of PKA in the leading edge of migrating cells is regulated by a mechano-chemical mechanism involving interplay between localized increases in cellular tension, influx of extracellular Ca2+, and activation of ADORA2B. We will test this hypothesis by determining the role of ADORA2B in mechanical activation of PKA during cell migration, delineating the mechanism of mechano-chemical activation/regulation of ADORA2B during cell migration, and determining the mechanistic hierarchy of contractility, Ca2+, and ADORA2B in regulating localized PKA activity and cell migration. At the end of the proposed studies, we will have established a paradigmatic pathway in which localized coupling of cellular mechanics to a GPCR signaling cascade regulates cytoskeletal dynamics and cell motility.

 描述（由申请人提供）：细胞与其微环境保持张力的动态平衡，并且这种“机械互易性”控制着多种细胞功能，包括细胞命运、形状和运动，尽管细胞感知的分子机制很重要。我们的实验室尚未完全了解 cAMP 依赖性蛋白激酶 (PKA) 在细胞前缘的富集和激活，并且这种定位对于细胞迁移非常重要。我们不断努力阐明细胞迁移过程中 PKA 的空间调节机制，最近发现局部 PKA 活性受到细胞张力的调节，特别是，当细胞收缩时，前缘 PKA 活性会迅速丧失。当受到机械拉伸时，PKA 以张力依赖性方式在拉伸方向上快速局部激活。最后，抑制 PKA 还会阻止 durotaxis（由 ECM 刚性和梯度引导的细胞迁移）。我们目前的重点是了解细胞张力与 PKA 局部调节的耦合机制。最近的初步数据表明，细胞收缩性和 PKA 的局部激活都依赖于细胞外 Ca2+ 通过拉伸激活通道 TRPM7 的流入。其他数据强烈表明，G 蛋白偶联受体 - A2B 腺苷受体 (ADORA2B) - 也在这一机制中发挥着重要作用。根据我们的观察，我们捕获了 A2B 腺苷受体的局部激活。迁移细胞前缘的 PKA 受到机械化学机制的调节，该机制涉及细胞张力局部增加、细胞外 Ca2+ 流入和 ADORA2B 激活之间的相互作用。我们将通过确定 ADORA2B 在机械激活中的作用来检验这一假设。细胞迁移过程中的 PKA，描绘细胞迁移过程中 ADORA2B 的机械化学激活/调节机制，并确定收缩性、Ca2+ 和ADORA2B 调节局部 PKA 活性和细胞迁移 在拟议研究结束时，我们将建立一个范式途径，其中细胞力学与 GPCR 信号级联的局部耦合调节细胞骨架动力学和细胞运动。