Transcriptional events controlling enteroendocrine cell differentiation

控制肠内分泌细胞分化的转录事件

基本信息

批准号：
9160624
负责人：
ANDREW B. LEITER
金额：
$ 37.69万
依托单位：
UNIV OF MASSACHUSETTS MED SCH WORCESTER
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-08-01 至 2020-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9160624
关键词：
Accounting Acetylation Automobile Driving BHLH Protein Binding Binding Sites Biogenic Amines Blood Cataloging Catalogs Cell Differentiation process Cell Line Cell Lineage Cells Chromatin Chromatin Structure Complex DNA Data Desire for food Diabetes Mellitus Disease Eating Endocrine Enhancers Ensure Enteroendocrine Cell Environment Epithelial Cells Event Figs - dietary Gene Expression Gene Expression Profiling Gene Targeting Genes Genetic Transcription Genome Genomics Goals High-Throughput Nucleotide Sequencing Homeostasis Hormones Individual Intestines Islets of Langerhans Knowledge Label Link Maps Mus National Human Genome Research Institute Non-Insulin-Dependent Diabetes Mellitus Obesity Organ PCAF gene Production Proteins Role STC1 gene Site Sp1 Transcription Factor Staging Stem cells Tissue-Specific Gene Expression Tissues Transcript Transcription Coactivator Transgenic Mice Variant Work cell type genome wide association study in vivo insulin secretion intestinal epithelium intestinal homeostasis knock-down member novel novel therapeutics peptide hormone programs protein expression self-renewal transcription factor transcriptome sequencing

项目摘要

Project Description Enteroendocrine cells (EECs) are one of five epithelial cell lineages in the intestine that arise from intestinal stem cells. EECs are notable for their secretion of peptide hormones and biogenic amines. Secreted products regulate food intake, energy homeostasis, insulin secretion and the function of most digestive organs. Relatively little is known about the transcriptional programs that drive enteroendocrine cell differentiation. Until recently, it has difficult to isolate enough EECs for gene expression analysis since EECs represent less than 2% of the intestinal epithelium. The ability to collect fluorescently labeled EECs from transgenic mice combined with technological improvements in high throughput sequencing, make it possible to consider gene expression studies in EECs that previously could not be done. Two basic helix loop helix transcription factors are critical for EEC differentiation. Neurogenin3 (Neurog3) is required for the earliest stages of EEC specification but can give rise to nonendocrine cell types. Expression of the bHLH protein NeuroD1 is expressed in all EECs, restricting cells to an endocrine cell fate. As a relatively weak transcriptional activator, it is not known how NeuroD1 drives cells to become EECs. Our understanding is further limited by the paucity of identified NeuroD1 targets in enteroendocrine cells. An increasing body of information has revealed that tissue specific expression depends on both the local chromatin environment and enhancer occupancy by multiple tissue specific transcription factors. The overall goals of this proposal are to identify NeuroD1 transcriptional targets, to identify other proteins that occupy sites close to NeuroD1, and determine how NeuroD1 activity is influenced by the local chromatin environment. In addition, the contribution of ubiquitously expressed transcription factors bound to nearby sites, to NeuroD1 transcriptional activity will be examined. The goal of Aim 1 is to identify genes that are activated by NeuroD1 in EECs and to identify other transcription factors that bind to DNA in close proximity with NeuroD1 to enhance target gene expression. Studies in Aim 2 will examine the broad role of RREB1 and LSD1, two members of the CtBP co-repressor complex that associate with NeuroD1 to potentiate transcription. The goal of Aim 3 is to determine the importance open chromatin subtypes and enhancer occupancy by multiple transcription factors in NeuroD1 driven tissue specific gene expression. The final goal of Aim3 will be to determine if any identified NeuroD1 enhancer clusters are linked to disease associated variants (SNPs) in the GWAS catalogue. Completion of the proposed studies will expand our knowledge about enteroendocrine cell differentiation and their potential impact on common diseases like diabetes and obesity.

项目描述肠内分泌细胞 (EEC) 是肠道中五种上皮细胞谱系之一，源自肠道干细胞。 EEC 以其分泌肽激素和生物胺而闻名。分泌产物调节食物摄入、能量稳态、胰岛素分泌和大多数消化器官的功能。对于驱动肠内分泌细胞分化的转录程序知之甚少。直到最近，很难分离足够的 EEC 用于基因表达分析，因为 EEC 代表的数量少于 2%的肠上皮。从转基因小鼠中收集荧光标记的 EEC 的能力结合高通量测序技术的进步，使考虑基因以前无法在 EEC 中进行表达研究。两种基本的螺旋环螺旋转录因子对于 EEC 的分化至关重要。 EEC 最早阶段需要 Neurogenin3 (Neurog3) 规范，但可以产生非内分泌细胞类型。 bHLH 蛋白 NeuroD1 的表达是在所有 EEC 中表达，限制细胞的内分泌细胞命运。作为一种相对较弱的转录激活因子，目前尚不清楚 NeuroD1 如何驱动细胞变成 EEC。我们的理解因缺乏而进一步受到限制肠内分泌细胞中已确定的 NeuroD1 靶点。越来越多的信息表明，组织特异性表达取决于局部染色质环境和增强子占据多种组织特异性转录因子。该提案的总体目标是识别 NeuroD1 转录目标，识别占据 NeuroD1 附近位点的其他蛋白质，并确定如何 NeuroD1 活性受局部染色质环境影响。此外，无处不在的贡献表达的转录因子与附近位点结合，对 NeuroD1 转录活性进行检查。这目标 1 的目标是识别 EEC 中由 NeuroD1 激活的基因并识别其他转录与 NeuroD1 非常接近的 DNA 结合的因子，以增强靶基因的表达。目标 2 的研究将检查 RREB1 和 LSD1 的广泛作用，这两个 CtBP 共阻遏物复合体的成员与 NeuroD1 结合以增强转录。目标 3 的目标是确定开放的重要性 NeuroD1驱动的组织特异性中多种转录因子的染色质亚型和增强子占据基因表达。 Aim3 的最终目标是确定是否有任何已识别的 NeuroD1 增强子簇与 GWAS 目录中的疾病相关变异 (SNP) 相关。完成拟议的研究将扩大我们对肠内分泌细胞分化及其对常见疾病潜在影响的了解糖尿病和肥胖症等疾病。