Epigenetic regulation of lens fiber cell differentiation: The role of DNA methyla

晶状体纤维细胞分化的表观遗传调控：DNA甲基化的作用

基本信息

批准号：
8229812
负责人：
MICHAEL L ROBINSON
金额：
$ 21.3万
依托单位：
MIAMI UNIVERSITY OXFORD
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-03-01 至 2014-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8229812
关键词：
Address Candidate Disease Gene Cell Cycle Cell Differentiation process Cell division Cells CpG dinucleotide Crystallins Cytosine DNA DNA Maintenance DNA Methylation DNA Methyltransferase DNA Modification Methylases DNA Modification Process Development E-Cadherin Enzymes Epigenetic Process Epithelial Epithelial Cells Epithelium Equilibrium Filament Gene Expression Gene Expression Profile Gene Expression Regulation Generations Genes Genetic Guanosine Histones Knock-out Knowledge Lens Fiber Maintenance Mammalian Cell Mammals Medicine Methylation Methyltransferase Modification Molecular Profiling Mus Mutation Organism Partner in relationship Patients Phenotype Play Pluripotent Stem Cells Proteins RNA RNA Sequences Regulation Relative (related person)Reporting Repression Role Stem cells Tissue-Specific Gene Expression Vertebrates Zebrafish cell type demethylation ds-DNA fiber cell filensin gene repression lens mutant next generation preference prevent promoter research study transcription factor

项目摘要

DESCRIPTION (provided by applicant): Lens fiber cell differentiation involves a coordinated change in gene expression. A number of genes including Pax6, FoxE3 and E-cadherin are expressed in lens epithelial cells but down-regulated in lens fiber cells. Conversely many other genes including Aquaporin0, 2- and 3-crystallins and lens-specific beaded filament proteins CP49 and filensin are not expressed in lens epithelial cells but are turned on in lens fiber cells. In recent years it has become increasingly clear that epigenetic modification (reversible covalent modification of DNA or histone proteins) of chromosomal DNA plays a major role in gene regulation. Among the best studied epigenetic modifications is methylation of cytosine in CpG dinucleotides in DNA. Methylation of DNA in mammalian cells is accomplished by Dnmt1, which is responsible for maintaining epigenetic methylation through cell divisions, and Dnmt3a and Dnmt3b, which are responsible for creating de novo methylation changes during development. Promoter DNA methylation is associated with transcriptional repression of genes. Despite the wealth of knowledge of transcription factors involved in lens development, very little is known about the epigenetic regulation of lens fiber cell differentiation. Recent evidence suggests that Dnmt1 and Dnmt3 activity are specifically required for lens development in zebrafish. We hypothesize that the balance between promoter methylation and demethylation is required for proper lens fiber cell differentiation, and that this balance will require the activity of both maintenance and de novo methylation activity. We propose that maintenance methylation will be required to prevent the expression of genes associated with fiber cell differentiation in the lens epithelium and that de novo methylation will be required to repress the expression of lens epithelial genes during fiber cell differentiation. We will investigate the role of DNA methylation in fiber cell differentiation using both conditional genetic strategies in mice lacking maintenance or de novo methylases in the lens lineage. We will use histological, immunological and high throughput next generation sequencing strategies to comprehensively investigate how DNA methylation influences lens fiber cell differentiation. PUBLIC HEALTH RELEVANCE: Recent experiments demonstrating that epigenetic reprogramming can convert differentiated cell types into pluripotent stem cells makes clear the critical importance for understanding the epigenetic regulation of the differentiated phenotype. We propose that the lens represents a unique opportunity to understand how epigenetic DNA methylation regulates differentiation. This understanding will be important not only for lens development, but for a global understanding of how to manipulate differentiated states, which is critical for the generation of patient-specific stem cells in medicine.

描述（由申请人提供）：镜头纤维细胞分化涉及基因表达的协调变化。包括PAX6，FOXE3和E-钙粘着蛋白在内的许多基因在晶状体上皮细胞中表达，但在晶状体纤维细胞中下调。相反，许多其他基因在内的基因，包括Aquaporin0，2-和3-晶格蛋白以及特异性珠丝蛋白CP49和FILENSIN在晶状体上皮细胞中未表达，但在透镜纤维细胞中打开。近年来，越来越清楚的是，染色体DNA的表观遗传修饰（可逆的DNA或组蛋白蛋白的可逆共价修饰）在基因调节中起主要作用。在DNA中，最佳研究表观遗传修饰是胞嘧啶的甲基化。 DNMT1在哺乳动物细胞中DNA的甲基化完成，该DNMT1负责通过细胞分裂维持表观遗传甲基化，而DNMT3A和DNMT3B则负责在发育过程中产生从头甲基化的变化。启动子DNA甲基化与基因的转录抑制有关。尽管对晶状体发育中涉及的转录因子有丰富的了解，但对晶状体纤维细胞分化的表观遗传调节知之甚少。最近的证据表明，DNMT1和DNMT3活性是斑马鱼晶状体发展所需的。我们假设启动子甲基化和脱甲基化之间的平衡是正确的晶状体纤维细胞分化所必需的，并且这种平衡将需要维护和从头甲基化活性的活性。我们建议需要维持甲基化以防止晶状体上皮中与纤维细胞分化相关的基因的表达，并且需要从头甲基化来抑制纤维细胞分化过程中晶状体上皮基因的表达。我们将使用透镜谱系中缺乏维持或从头甲基酶的小鼠中使用条件遗传策略来研究DNA甲基化在纤维细胞分化中的作用。我们将使用组织学，免疫学和高通量下一代测序策略来全面研究DNA甲基化如何影响透镜纤维细胞分化。公共卫生相关性：最近的实验表明，表观遗传重编程可以将分化的细胞类型转换为多能干细胞，这清楚地清楚了了解分化表型的表观遗传调节至关重要的重要性。我们建议镜头代表了一个独特的机会，可以理解表观遗传学DNA甲基化如何调节分化。这种理解不仅对晶状体的发展至关重要，而且对于如何操纵分化状态的全球理解，这对于医学中患者特异性干细胞的产生至关重要。