Transcriptional Mechanisms Governing Beta Cell Differentiation

控制β细胞分化的转录机制

• 批准号: 7476165
• 负责人: Raghavendra G Mirmira
• 金额: $ 3.73万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7476165
• 关键词: Address; Applications Grants; Beta Cell; Biochemical; Biological Assay; Cell Differentiation process; Cell Line; Cell Nucleus; Cells; Chromatin; Chromatin Structure; Classification; Complex; Development; Diabetes Mellitus; Embryonic Development; Euchromatin; Event; Fluorescence; Gene Expression; Gene Expression Regulation; Gene Targeting; Genes; Genetic Transcription; Heterochromatin; Holoenzymes; Imaging Techniques; In Vitro; Insulin; Islets of Langerhans; Lead; Life; Link; Mammalian Cell; Mediating; Molecular; Nature; Pathogenesis; Pattern; Proteins; Publishing; RNA Polymerase II; RNA Processing; Range; Rate; Recruitment Activity; Relative (related person); Research Personnel; Role; Small Interfering RNA; Structure of beta Cell of islet; Testing; Transcription Coactivator; base; cell type; cellular imaging; chromatin immunoprecipitation; chromatin remodeling; cofactor; concept; homeodomain; insulin secretion; islet; novel strategies; physical state; programs; research study; transcription factor

The absolute or relative deficiency of insulin secretion by the pancreatic beta cell underlies the pathogenesis of most forms of diabetes mellitus. Promising new approaches to the treatment or cure of diabetes will come from attempts recapitulate beta cell gene expression patterns in non-beta cell types. The long-range objective of this ongoing grant application is to define the biochemical mechanisms by which transcription factors direct gene expression in the developing and mature beta cell. In this application, we propose to extend upon our published studies of the mechanisms underlying the beta cell transcription factors Nkx6.1 and Pdx-1, and thereby merge established concepts in beta cell gene regulation with exciting and emerging themes in transcriptional complex formation and chromatin structure. Nkx6.1 and Pdx-1 are necessary for both the embryonic development and eventual function of beta cells. We hypothesize that these factors participate in key transcriptional complexes that are responsible for the remodeling of chromatin and the subsequent recruitment of basal transcriptional machinery. These effects result in either the activation or silencing of selective genes that lead to normal beta cell development and function. To test this hypothesis, our specific aims are directed toward a systematic analysis of the transcriptional complexes mediated by Pdx-1 and Nkx6.1 (Aim 1), the consequences of these complexes on chromatin structure (Aim 2), and their effects on the recruitment/activation of basal transcriptional machinery (Aim 3). Aim 1: Characterize transcriptional complexes involving Pdx-1 and Nkx6.1 and determine how they regulate target gene expression in the beta cell. Aim 2: Determine the role of Pdx-1 and Nkx6.1 complexes in modulating chromatin structure at target genes Aim 3. Determine the role of Pdx-1 and Nkx6.1 complexes in the recruitment of basal transcriptional machinery We propose to use a combination of biochemical assays and live cell imaging techniques in both cell lines and primary isolated islets to address each of these aims. We believe that the proposed studies will provide the frameworkfor elucidating the molecular events governing b cell development and function

胰腺β细胞分泌胰岛素的绝对或相对不足是发病机制的基础 大多数糖尿病的症状。治疗或治愈糖尿病的有希望的新方法将会出现 从尝试概括非β细胞类型中的β细胞基因表达模式。远程 这项正在进行的拨款申请的目的是确定转录的生化机制， 这些因子指导发育和成熟的β细胞中的基因表达。在本申请中，我们建议 扩展我们发表的β细胞转录因子Nkx6.1的机制的研究 和Pdx-1，从而将β细胞基因调控中已建立的概念与令人兴奋的和新兴的概念相结合， 转录复合体形成和染色质结构的主题。Nkx6.1和Pdx-1是必要的， 胚胎发育和β细胞的最终功能。我们假设这些因素 参与关键的转录复合物，负责染色质的重塑和 随后募集基础转录机器。这些效应导致激活或 沉默导致正常β细胞发育和功能的选择性基因。为了验证这个假设， 我们的具体目标是系统地分析转录复合物， Pdx-1和Nkx6.1（目的1），这些复合物对染色质结构的影响（目的2），以及它们对染色质结构的影响。 对基础转录机制的募集/激活的影响（目的3）。 目的1：表征涉及Pdx-1和Nkx6.1的转录复合物，并确定它们如何调节 β细胞中的靶基因表达。 目的2：确定Pdx-1和Nkx6.1复合物在调节靶基因染色质结构中的作用 目标3.确定Pdx-1和Nkx6.1复合物在基础转录因子的募集中的作用。 机械 我们建议在两种细胞系中使用生物化学测定和活细胞成像技术的组合 和主要的孤立小岛来实现这些目标。我们相信，拟议的研究将提供 阐明控制B细胞发育和功能的分子事件