GENE REGULATION DURING MACROPHAGE ACTIVATION

该项目将研究基因调控过程中的 巨噬细胞(MP)由强刺激性干扰素-γ(干扰素-γ)激活 Gamma)。在过去的几年里，我们在克隆方面取得了成功 MP对干扰素-γ的反应所表达的一些基因。它 我们的信念是，理解对这种 诱导基因将提供对这些分子变化的理解 参与开发一种激活的MP。一种模式基因 在这些研究中发现，MAG-1具有组织特异性和 干扰素-γ和IS刺激特异性表达的研究 在不同分化阶段的MP中有差异表达。 该基因的表达受一条意想不到的干扰素途径控制。 伽马介导的转录调控。基于这些初始的 现在，我们建议从三个方面探讨干扰素-γ- 刺激MP激活反应。我们会辨认抄本 负责干扰素-γ介导的基因诱导的因子(S) 使用MAG-1启动子区域作为我们的 模特。我们将使用各种分子方法来表征 与关键启动子元件结合的因子对干扰素-γ的反应 并确定这些因素与这些蛋白质之间的关系 被证明参与了经典的干扰素-α或干扰素-γ介导的 转录调控途径。然后我们将分析 MAG-1基因在干扰素诱导的激活反应中的作用 通过该基因在正常不表达的MP中的表达 或通过抑制基因表达。基因表达的影响 然后将监测MP激活响应的各个方面。 我们还将剖析差异调控的分子基础。 MP成熟过程中基因表达的变化。这些研究将使用 MP细胞系和原代骨髓来源MP作为化学靶点的研究 或细胞因子诱导分化。然后，我们将检查这些更改 在干扰素-γ介导的转录调控和基因诱导中 在MP发育的不同阶段表达。这样做的结果 这项工作将提供有关分子机制的新信息 控制干扰素-γ诱导MP活化的机制。

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.