NFAT Transcription in Vascular Smooth Muscle

说明书(申请人提供)：免疫抑制剂环孢素A (CsA)和FK506会导致一系列严重的副作用，包括受损 心血管功能。这不仅是一个严重的临床问题，而且 表明受免疫抑制剂影响的细胞过程对 维持正常的心血管内环境平衡。通过绑定到任何一个 在两种不同的细胞适配器中，两种药物都能抑制磷酸酶 钙调神经磷酸酶。一个被称为核因子的转录因子家族 激活的T细胞(NFAT)是众所周知的钙调神经磷酸酶底物。虽然 最初被认为是T细胞受限的研究表明，NFAT亚型 广泛分布于全身非淋巴组织。申请人 已经发表了几项研究，支持NFAT可以服务于 作为一种转录效应器，由各种激素引起的信号传递， 血管平滑肌和血管内皮细胞亚群中的类耳壳蛋白和生长因子 内皮细胞。我们推测NFAT参与了信号的调制。 这些生理激动剂诱导的血管基因表达程序 干扰NFAT介导的转录可能有助于 免疫抑制药物毒性。如果是这样的话，总的来说，NFAT很可能是一个关键 重要的动态平衡过程的调节器，其目标将是巨大的 有趣的发现。该项目的总体目标包括推导出 更好地理解NFAT介导的转录是如何在 血管平滑肌细胞背景及其可能参与的基因 监管。为了探索这一点，我们将评估四种不同的NFAT亚型 是差异调节的，并驱动血管基因的独特模式 表情。由于在平滑肌细胞中没有NFAT基因靶点 明确地说，我们将继续进行有力支持 假设NFATs反式激活VSMC中的COX-2和IL-6基因。我们 我还将研究cAMP依赖的激酶通路的共同激活如何调节 NFAT转录。最后，我们将研究 通过研究CsA治疗和NFAT基因切割如何扰乱NFAT的功能 用小鼠模型影响血管功能。该项目将利用 创新高效的重组基因表达技术在培养细胞中的应用 模型，加上最先进的生理评估。我们期望的是 这些发现可能会为NFAT在以下方面的作用提供重要的新见解 血管平滑肌及其与免疫抑制剂诱导的关系 血管功能障碍。

DESCRIPTION (provided by the applicant): The immunosuppressants cyclosporin A (CsA) and FK506 cause a spectrum of serious side effects, including impaired cardiovascular function. This is not only a serious clinical problem, but also indicates that cellular processes affected by immunosuppressant are crucial for the maintenance of normal cardiovascular homeostasis. Through binding to either of two distinct cellular adapters, both drugs inhibit the phosphatase calcineurin. A family of transcription factors termed the nuclear factors of activated T-cells (NFAT) are well-known calcineurin substrates. Although initially considered T-cell restricted, studies indicate that NFAT isoforms are widely distributed in non-lymphoid tissues throughout the body. The applicant has published several studies supporting the general notion that NFAT can serve as a transcriptional effector for signaling evoked by various hormones, autacoids and growth factors within subsets of vascular smooth muscle and endothelial cells. We speculate that NFAT participates in the modulation of vascular gene expression programs elicited by such physiological agonists and that interference with NFAT mediated transcription may contribute to immunosuppressant drug toxicity. If so, on balance, NFAT likely serves as a key regulator of important homeostatic processes, and its targets would be of great interest to discover. General objectives of this project include deriving a better understanding of how NFAT mediated transcription operates in a vasculature smooth muscle cell context, and what genes it may be involved in regulating. To explore this, we will assess whether four distinct NFAT isoforms are differentially regulated and drive unique patterns of vascular gene expression. Since no NFAT gene targets in smooth muscle cells have been definitively described, we will carry forward studies that strongly support the hypothesis that NFATs trans-activate the COX-2 and IL-6 genes within VSMC. We will also study how co-activation of cAMP-dependent kinase pathways modulate NFAT transcription. Lastly, we will examine the physiologic consequences of disrupted NFAT function by studying how CsA treatment and NFAT gene ablation influence vascular function using murine models. The project will exploit innovative and powerful recombinant gene expression techniques in cultured cell models, coupled with state-of-the-art physiological assessments. Our expected findings are likely to provide important new insights into the role of NFAT in vascular smooth muscle and its relationship to immunosuppressant-induced vascular dysfunction.