Genomic Mapping of C-G Epigenetic Programs in Hematovascular Progenitor Cells

血管祖细胞中 C-G 表观遗传程序的基因组图谱

• 批准号: 7486172
• 负责人: Beverly Marie Emerson
• 金额: $ 39.92万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-20 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7486172
• 关键词: Biochemical; Bioinformatics; Biological; Biological Assay; Biological Process; Cell Differentiation process; Cell Lineage; Cells; Characteristics; Chemicals; Chromatin; Cis-Acting Sequence; Code; Commit; Condition; DNA; DNA Methylation; DNA Modification Process; DNA-Protein Interaction; Data; Development; Elements; Epigenetic Process; Functional RNA; Gene Expression; Genes; Genetic Transcription; Genome; Genomics; Goals; Hematological Disease; Hematopoietic; Hematopoietic System; Hot Spot; Immunofluorescence Immunologic; Locus Control Region; Maps; Molecular Profiling; Mus; Output; Pattern; Play; Population; Replacement Therapy; Research Personnel; Role; Site; Somatic Cell; Specific qualifier value; Staging; Stem cells; System; Therapeutic; Tissues; Transplantation; Undifferentiated; Work; base; chromatin immunoprecipitation; embryonic stem cell; epigenomics; insight; mammalian genome; mouse genome; novel; pluripotency; progenitor; programs; promoter; restriction enzyme; tool

DESCRIPTION (provided by applicant): The focus of this proposal is to understand how a pluripotent cell commits to a specific fate at the earliest stages of differentiation. Cell identity is determined by the transcriptional potential of its genomic DNA. This is achieved, in large part, through specific chemical modifications of DNA and chromatin that epigenetically programs gene activity. A critical aspect of epigenetic programming is DNA methylation, which "hard-wires" the genome by limiting transcriptional output to those programs that control cellular specialization. Because this occurs most actively in stem cells, the mouse ES/EB system is especially valuable for capturing the complete and ordered programming of a pluripotent genome in its early stages and in quantities that are amenable to analyses. We propose to purify a discrete population of hematovascular progenitor cells from differentiating mouse ES cells and compare the DNA methylation and RNA expression profiles with those of differentiated progenitors that do not possess a hematovascular potential. In this way, we can discriminate between DNA methylation patterns that are associated with differentiation in general and those that are specific to the hematopoietic lineage. We will use a blended high-throughput epigenetic/genic/bioinformatic platform to identify the initial sites of DNA methylation within a genome as it transitions from pluripotency to a committed state, couple this information with RNA expression analyses, and compare it with similar data obtained from cells of distinct developmental potential. Functional verification of hematovascular-specific methylated DNA regions that we identify will be performed in ES cell differentiation assays to examine the biological role of these regions in cell lineage commitment. By employing genomic tools, we hope to establish a basis for how cells codify their cell fate choices. An important aspect of our work is its possible application to cell replacement therapy for blood diseases. For example, long-term replacement of the hematopoietic system will necessitate transplantation of the most immature cells, such as those derived from hematovascular progenitor cells. Our work will generate biochemical quantities of highly purified populations of this important precursor, which will be used to define its epigenomic signature through DNA methylation and RNA expression profiling. We hope to apply this platform to unambiguously identify the precise epigenetic characteristics of any cell within a population that is to be evaluated for its therapeutic potential.

描述（由申请人提供）：该提案的重点是了解多能细胞如何在分化的最早阶段实现特定的命运。细胞身份由其基因组 DNA 的转录潜力决定。这在很大程度上是通过对 DNA 和染色质进行特定的化学修饰来实现的，这些化学修饰通过表观遗传方式编程基因活性。表观遗传编程的一个关键方面是 DNA 甲基化，它通过限制那些控制细胞特化的程序的转录输出来“硬连接”基因组。由于这种情况在干细胞中最为活跃，因此小鼠 ES/EB 系统对于捕获多能基因组早期阶段的完整有序编程并以易于分析的数量特别有价值。我们建议从分化的小鼠 ES 细胞中纯化出离散的血管祖细胞群，并将 DNA 甲基化和 RNA 表达谱与不具有血管潜能的分化祖细胞的 DNA 甲基化和 RNA 表达谱进行比较。通过这种方式，我们可以区分与一般分化相关的 DNA 甲基化模式和与造血谱系特异的 DNA 甲基化模式。我们将使用混合的高通量表观遗传/基因/生物信息学平台来识别基因组内从多能性转变为定型状态时 DNA 甲基化的初始位点，将该信息与 RNA 表达分析结合起来，并将其与从具有不同发育潜力的细胞获得的类似数据进行比较。我们将在 ES 细胞分化测定中对我们确定的血管特异性甲基化 DNA 区域进行功能验证，以检查这些区域在细胞谱系定型中的生物学作用。通过使用基因组工具，我们希望为细胞如何编码其细胞命运选择奠定基础。我们工作的一个重要方面是其可能应用于血液疾病的细胞替代疗法。例如，造血系统的长期更换将需要移植最不成熟的细胞，例如源自血管祖细胞的细胞。我们的工作将产生这种重要前体的高度纯化群体的生化数量，这些群体将用于通过 DNA 甲基化和 RNA 表达谱来定义其表观基因组特征。我们希望应用这个平台来明确识别群体中任何细胞的精确表观遗传特征，以评估其治疗潜力。