REGULATION OF TRYPTASE EXPRESSION IN MAST CELLS

小鼠肥大细胞（MC）表达三种同源的胰蛋白酶（mMCP-6、mMCP-7和mMCP-11），其基因聚集在17号染色体上。mMCP-6和mMCP-7协同作用，以不同的方式调节中性粒细胞和嗜酸性粒细胞向炎症部位的外渗。在mc介导的炎症反应中，mMCP还在组织中凝块形成和纤维蛋白原/整合素依赖的细胞反应的调节中发挥重要作用。由于它们在先天免疫和适应性免疫中的重要性，MC胰蛋白酶在许多水平上受到调节。然而，转录和转录后机制似乎是MC控制它们表达的胰蛋白酶的主要方式。最近在过敏和哮喘患者的血液中发现含有大量胰蛋白酶的细胞，这表明迫切需要在过敏和哮喘患者的血液中含有大量的胰蛋白酶，这表明迫切需要了解这些蛋白酶在正常和病理情况下是如何调节的。因此，项目1的长期目标是在分子水平上了解MC如何控制编码同源但功能不同的胰蛋白酶的转录本的稳态水平。特异性目的1的目的是阐明为什么胰蛋白酶基因聚集在17号染色体上。在这些研究中，基因甲基化和组蛋白活化在胰蛋白酶表达中的作用将被评估。特异性目标2的目标是确定三种胰蛋白酶基因的转录是如何被差异调节的。在这些研究中，将鉴定调节每个基因转录的顺式作用元件和反式作用因子。一个控制元件是否调控培养基因的位点将被确定。特异性目标3的目标是了解MC用来控制的两种非常不同的转录后机制。细胞中功能性和非功能性转录本的稳态水平。在这些研究中，将鉴定三种胰蛋白酶转录本中的顺式作用元件和MC中共同控制每种胰蛋白酶转录本稳定性的反式作用rna结合蛋白。

Mouse mast cells (MC) express three homologous tryptases (designated mMCP-6, mMCP-7, and mMCP-11), whose genes are clustered on chromosome 17. mMCP-6 and mMCP-7 work in concert to differentially regulated the extravasation of neutrophils and eosinophils into inflammatory sites. mMCP also plays an important role in the regulation of clot formation and fibrinogen/integrin-dependent cellular responses in tissue during MC-mediated inflammatory reactions. Because of their importance in innate and adaptive immunity, MC tryptases are regulated at a number of levels. Nevertheless, transcriptional and post-transcriptional mechanisms appear to be the major ways MC control which tryptases they express. The recent identification of cells that contain substantial amounts of tryptase in the blood of patients with allergy and asthma indicates the urgent need contain substantial amounts of tryptase in the blood of patients with allergy and asthma indicates the urgent need to understand how these proteases are regulated in normal and pathologic circumstances. Thus, the long-term objective of Project 1 is to understand the molecular level how MC control the steady-state levels of the transcripts that encode homologous, but functionally distinct, tryptases. The goal of Specific Aim 1 is to elucidate why the tryptase genes are clustered genes are clustered on chromosome 17. In these studies, the role of gene methylation and histone activation in tryptase expression will be evaluated. The goal of Specific Aim 2 is to determine how transcription of the three tryptase genes is differentially regulated. In these studies, the cis-acting elements and trans-acting factors that regulate the transcription of each gene will be identified. Whether or not a locus a control element regulates of the cultured genes will be determined. The goal of Specific Aim 3 is to understand the two very different post-transcription mechanisms the MC uses to control. the steady-state levels of functional and non-functional transcripts in cells. In these studies, the cis-acting elements in the three tryptase transcripts and the trans-acting RNA-binding proteins in the MC that work together to control the stability of each tryptase transcript will be identified.