REGULATION OF VASCULAR SMOOTH MUSCLE MRNA STABILITY

血管平滑肌 mRNA 稳定性的调节

• 批准号: 6330092
• 负责人: Thomas J. Murphy
• 金额: $ 22.21万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2001-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6330092
• 关键词: RNA binding protein; angiotensin receptor; angiotensins; bacteriophage lambda; biological signal transduction; chemical stability; gene expression; genetic techniques; genetic translation; isoproterenol; messenger RNA; molecular cloning; muscle contraction; northern blottings; nucleic acid structure; protein biosynthesis; protein kinase A; receptor expression; site directed mutagenesis; transcription factor; vascular smooth muscle; western blottings; yeasts

Vascular smooth muscle cell (VSMC) populations undergo rearrangements from normal, contractile to pathological states in the course of diseases such as atherosclerosis and hypertension. It is self-evident that altered gene expression patterning not only accompanies this, but is intrinsic to the vascular remodeling process of disease. A picture has emerged in which genes typically associated with contractile function are down-regulated and replaced by those more supportive of a proliferative or pathological state. However, very little is known about mechanisms that regulate these shifts in VSMC gene expression patterns, or whether this represents an orchestrated process. Persistent or skewed exposure to a diverse array of extracellular factors, including growth factors, cytokines, lipids, hormones and neurotransmitters, have been implicated in VSMC dysfunction. This project will explore to what extent diverse extracellular signals may share common molecular mechanisms to down-regulate the expression of contractile- function genes in VSMC. The model system in this project is a microcosm of the vascular remodeling process. It involves cultured VSMC and an examination of the molecular mechanisms responsible for extracellular signal-induced destabilization of the mRNA encoding the angiotensin II AT1-receptor (AT1-R), serving as a prototypic contractile gene. That AT1-R mRNA is destabilized by representative growth factors, by hormones and cAMP-elevating agents, all in a translationally- and transcriptionally-coupled process, which suggests that a factor(s) is(are) induced to mediate this. The aims of this study are: 1) to determine if a common signaling pathway integrates AT1-R mRNA decay induced by diverse classes of extracellular factors; 2) to establish the elements in the AT1-R mRNA molecule necessary for its destabilization in order to understand mechanisms for how specific mRNA's might be targeted by this destabilization process; 3) to determine to what extent AT1-R mRNA destabilizing signals alter translation of the mRNA and to establish the orle of AT1-R mRNA translation in its destabilization; 4) to isolate and clone documented AT1-R mRNA binding proteins induced by extracellular signals, as potential candidate factors involved in VSMC mRNA destabilization. State-of-the-art molecular genetic approaches will be exploited to manipulate VSMC gene expression.

血管平滑肌细胞 (VSMC) 群体发生重排 从正常状态、收缩状态到病理状态 动脉粥样硬化和高血压等疾病。这是不言而喻的 改变基因表达模式不仅伴随着这一点，而且 是疾病血管重塑过程所固有的。 一张图片 已经出现了通常与收缩相关的基因 功能被下调并被更支持的功能所取代 增殖或病理状态。 然而，人们知之甚少 关于调节 VSMC 基因表达变化的机制 模式，或者这是否代表一个精心策划的过程。 持续或偏向地暴露于多种细胞外物质 因子，包括生长因子、细胞因子、脂质、激素和 神经递质，与 VSMC 功能障碍有关。 这 项目将探索不同的细胞外信号在多大程度上可以 具有共同的分子机制来下调表达 VSMC 中的收缩功能基因。 本项目的模型系统 是血管重塑过程的一个缩影。 这涉及到文化 VSMC 和对负责的分子机制的检查 细胞外信号诱导编码 mRNA 的不稳定 血管紧张素 II AT1 受体 (AT1-R)，作为原型收缩 基因。 AT1-R mRNA 因代表性生长因子而不稳定， 通过激素和 cAMP 升高剂，所有这些都以翻译和 转录耦合过程，这表明一个因素 被诱导来调解这一点。 本研究的目的是：1） 确定共同信号通路是否整合 AT1-R mRNA 衰减 由多种细胞外因子诱导； 2）建立 AT1-R mRNA 分子中对其不稳定所必需的元件 为了了解特定 mRNA 的机制 成为这一破坏稳定进程的目标； 3）确定到什么程度 AT1-R mRNA 不稳定信号改变 mRNA 的翻译并 建立AT1-R mRNA翻译在其不稳定中的作用； 4） 分离和克隆记录的 AT1-R mRNA 结合蛋白 细胞外信号，作为参与 VSMC 的潜在候选因素 mRNA 不稳定。 最先进的分子遗传学方法 将被用来操纵 VSMC 基因表达。