GENE REGULATION DURING MACROPHAGE ACTIVATION

该项目将研究基因调控过程中， 巨噬细胞（MP）激活的强效刺激干扰素-γ（IFN-γ） γ）。 在过去的几年里，我们已经成功地克隆了 MP对IFN-γ应答时表达的许多基因。 它 我们坚信，理解这种监管机制， 诱导基因将提供对这些分子变化的理解 参与了一个激活的MP的发展。 一个模型基因 在这些研究中鉴定的MAG-1表现出组织特异性， 刺激特异性表达的IFN-γ， 在不同分化阶段的MP中差异表达。 该基因的表达由IFN-γ的一个意想不到的途径控制。 γ-介导的转录调节。 基于这些初始 研究，我们现在建议探索IFN-γ的三个方面， 刺激MP激活反应。 我们将识别转录 负责IFN-γ介导的基因诱导的因子， 交替信号通路，使用mag-1启动子区域作为我们的 模型 我们将使用各种分子方法来表征 与IFN-γ应答的关键启动子元件结合的因子 并确定这些因素与这些蛋白质的关系 显示参与经典的IFN-α或IFN-γ介导的 转录调控的途径。 然后我们将分析 mag-1基因对IFN-γ诱导的活化反应的贡献 γ，通过该基因在正常非表达MP中的表达， 或通过抑制基因表达。 基因表达的影响 然后将监视MP激活响应的各个方面。 我们还将剖析差异调节的分子基础 MP成熟过程中的基因表达。 这些研究将使用 MP细胞系和原代骨髓来源的MP作为化学治疗的靶点 或细胞因子诱导的分化。 然后我们将研究这些变化 在IFN-γ介导转录调节和基因诱导中 在MP发育的不同阶段表达。 的结果 这项工作将提供有关分子机制的新信息 其控制MP激活的IFN-γ诱导。

This project will examine gene regulation during the process of macrophage (MP) activation by the potent stimulus interferon-gamma (IFN- gamma). Over the past several years, we have been successful in cloning a number of genes that are expressed by MP in response to IFN-gamma. It is our conviction that understanding the mechanisms of regulation of such induced genes will provide an understanding of those molecular changes involved in the development of an activated MP. One model gene identified in these studies, mag-1, exhibits tissue-specific and stimulus-specific expression in response to IFN-gamma and is differentially expressed in MP at distinct differentiation stages. Expression of this gene is controlled by an unexpected pathway of IFN- gamma-mediated transcriptional regulation. Based on these initial studies, we now propose to explore three aspects of the IFN-gamma- stimulated MP activation response. We will identify the transcription factor(s) responsible for IFN-gamma-mediated induction of genes through the alternate signaling pathway, using the mag-1 promoter region as our model. We will use a variety of molecular approaches to characterize the factors binding to the critical promoter element in response to IFN-gamma and to determine the relationship of these factors to those proteins shown to be involved in the classical IFN-alpha- or IFN-gamma-mediated pathways of transcriptional regulation. We then will analyze the contribution of the mag-1 gene to the activation response induced by IFN- gamma, through the expression of this gene in normally non-expressing MP or through inhibition of gene expression. The effect of gene expression on various aspects of the MP activation response will then be monitored. We also will dissect the molecular basis of the differential regulation of gene expression during MP maturation. These studies will use both a MP cell line and primary bone marrow-derived MP as targets of chemical or cytokine induced differentiation. We then will examine the changes in IFN-gamma-mediated transcriptional regulation and induction of gene expression at different stages of MP development. The results of this work will provide novel information concerning the molecular mechanisms that control IFN-gamma induction of MP activation.