Transcriptional Mechanisms Governing Beta Cell Differentiation

胰岛β细胞分泌胰岛素的绝对或相对不足是其发病的基础。 大多数形式的糖尿病。治疗或治愈糖尿病的有希望的新方法将会出现 从尝试中总结出非β细胞类型中的β细胞基因表达模式。长距离的 这项正在进行的拨款申请的目标是定义转录的生化机制 在发育和成熟的β细胞中，因子指导基因的表达。在本申请中，我们建议 继续我们已发表的关于β细胞转录因子Nkx6.1潜在机制的研究 和PDX-1，从而将β细胞基因调控的既定概念与令人兴奋的和新兴的 转录复合体形成和染色质结构中的主题。Nkx6.1和PDX-1是必需的 包括胚胎发育和β细胞的最终功能。我们假设这些因素 参与负责染色质重塑的关键转录复合体和 随后基础转录机制的招募。这些影响会导致激活或 沉默导致正常β细胞发育和功能的选择性基因。为了检验这一假设， 我们的具体目标是系统地分析由 PDX-1和Nkx6.1(目标1)，这些络合物对染色质结构的影响(目标2)，以及它们的 对基本转录机制的招募/激活的影响(目标3)。 目的1：鉴定涉及PDX-1和Nkx6.1的转录复合体，并确定它们是如何调节的 目的基因在β细胞中的表达。 目的2：确定PDX-1和Nkx6.1复合体在调控靶基因染色质结构中的作用 目的3.确定PDX-1和Nkx6.1复合体在基础转录招募中的作用 机械 我们建议在这两种细胞系中结合使用生化分析和活细胞成像技术。 和主要的孤立小岛，以满足这些目标中的每一个。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的框架

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