Regualtion of visceral smooth muscle-specific gene expression during development.

发育过程中内脏平滑肌特异性基因表达的调节。

• 批准号: 7628017
• 负责人: BRIAN Paul HERRING
• 金额: $ 31.54万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-30 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7628017
• 关键词: Affect; Attenuated; Binding; Binding Sites; Biological Assay; Biological Models; Co-Immunoprecipitations; Contractile Proteins; Crohn' s disease; Data; Defect; Development; Disease; Dominant-Negative Mutation; Family member; Future; Gallbladder; Gastrointestinal tract structure; Gene Expression; Genes; Genetic Transcription; Goals; Indium; Inflammatory Bowel Diseases; Intestinal Diseases; Knowledge; Lead; Ligands; Link; Longitudinal Studies; MADH4 gene; Mediating; Megacolon; Mus; Pathology; Physiological; Play; Property; Protein Binding; Proteins; Publishing; Reporter; Reporter Genes; Role; Small Interfering RNA; Smooth Muscle; Smooth Muscle Myocytes; System; Systems Analysis; Testing; Therapeutic Agents; Tissues; Trans-Activators; Transgenes; Visceral; cell motility; design; factor A; gastrointestinal; in vivo; inhibitor/antagonist; knockout gene; myocardin; promoter; protein function; research study; telokin; transcription factor

DESCRIPTION (provided by applicant): Smooth muscle cells (SMCs) in different tissues express distinct groups of proteins that give each tissue unique physiological properties. However, few studies have comprehensively defined the transcription regulatory networks that are responsible for these tissue-specific properties of SMCs. Experiments described in this proposal will begin to fill this gap in our knowledge by defining the transcription regulatory networks that direct gene expression in SMCs in different tissues of the GI tract. Unraveling these mechanisms is crucial for understanding the pathology of many intestinal diseases that are associated with altered contractility resulting from changes in expression of smooth muscle-specific proteins. Our preliminary studies have demonstrated that the telokin promoter provides a unique model system for the analysis of transcription factors that regulate gene expression, specifically in GI SMCs. We propose that Sox and SMAD proteins, which bind to the -190 to -90 region of the telokin promoter, collaborate with SRF and other factors that bind to the AT/CArG (-90 to -56) region, to drive telokin expression specifically in SMCs of the GI tract. Three specific aims are proposed to test this hypothesis. For Aim 1, the physiological roles of Sox and SMAD proteins in regulating telokin expression will be determined. In addition, the importance of the Sox and SMAD binding sites in the telokin promoter for expression in GI SMC in vivo will be confirmed. Our previous studies have identified several trans-acting factors that bind to the AT/CArG elements in the telokin promoter. Experiments described in Aim 2 will determine which of these factors cooperate with Sox and SMAD proteins to direct telokin gene expression in GI SMC. One of the proteins that binds to the AT/CArG region is Foxf1 and as published and preliminary data suggest that Foxf1 plays an important role in GI tract development, the function of this protein will be further investigated in mice harboring a smooth muscle-specific knockout of the gene (Aim 3). Together these studies will allow us to identify the transcription regulatory network that controls expression of contractile proteins in GI smooth muscle tissues. Future studies, will examine how expression of these transcription factors is altered in diseases that affect GI motility. This will allow us to link changes in specific transcription factors to altered expression of contractile proteins and subsequent altered contractility of diseased tissue. Project Narrative: The goal of our studies is to identify the transcription factors that control the differentiation state of gastrointestinal smooth muscle cells. The differentiation state of smooth muscle is altered, resulting in impaired contractility, in numerous pathological conditions such as Crohns disease, inflammatory bowel disease, idiopathic megacolon and Hirschsprungs disease. Identifying the transcription factors that are dysregulated is an essential step towards designing appropriate therapeutic agents to treat the motility defects that occur in these diseases.

描述（由申请人提供）：不同组织中的平滑肌细胞（SMC）表达不同的蛋白质组，这些蛋白质组赋予每个组织独特的生理特性。然而，很少有研究已经全面定义了负责这些组织特异性的SMC的转录调控网络。本提案中描述的实验将开始通过定义指导胃肠道不同组织中SMC基因表达的转录调控网络来填补我们知识中的这一空白。解开这些机制对于理解许多肠道疾病的病理学至关重要，这些疾病与平滑肌特异性蛋白表达变化引起的收缩性改变有关。我们的初步研究表明，telokin启动子提供了一个独特的模型系统，用于分析转录因子，调节基因的表达，特别是在胃肠道平滑肌细胞。我们提出，Sox和SMAD蛋白，结合到-190到-90区域的telokin启动子，与SRF和其他因子，结合到AT/CArG（-90到-56）区域，以驱动telokin表达特异性在胃肠道的SMC。提出了三个具体目标来检验这一假设。对于目标1，将确定Sox和SMAD蛋白在调节端蛋白表达中的生理作用。此外，将证实在体内GI SMC中表达的端蛋白启动子中的Sox和SMAD结合位点的重要性。我们以前的研究已经确定了几个反式作用因子结合的AT/CArG元件在telokin启动子。目的2中描述的实验将确定这些因子中的哪一个与Sox和SMAD蛋白合作来指导GI SMC中的telokin基因表达。结合AT/CArG区域的蛋白质之一是Foxf 1，已发表的初步数据表明Foxf 1在胃肠道发育中起重要作用，将在携带平滑肌特异性基因敲除的小鼠中进一步研究该蛋白质的功能（目的3）。总之，这些研究将使我们能够确定控制胃肠道平滑肌组织中收缩蛋白表达的转录调控网络。未来的研究，将检查这些转录因子的表达是如何改变的疾病，影响胃肠道运动。这将使我们能够将特定转录因子的变化与收缩蛋白表达的改变以及随后病变组织收缩性的改变联系起来。 项目叙述：本研究的目的是鉴定调控胃肠平滑肌细胞分化状态的转录因子。平滑肌的分化状态改变，导致收缩性受损，在许多病理条件下，如克罗恩病，炎性肠病，特发性巨结肠和Hirschsprungs病。鉴定失调的转录因子是设计适当的治疗剂以治疗这些疾病中发生的运动缺陷的重要步骤。