Regulation of Age-Associated Heterochromatin Formation

年龄相关异染色质形成的调节

• 批准号: 8520146
• 负责人: Jill Kreiling
• 金额: $ 11.65万
• 依托单位: BROWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-30 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8520146
• 关键词: Address; Age; Age of Onset; Aging; Aging-Related Process; Animals; BMI1 gene; Beryllium; Binding; Bioinformatics; Biological Assay; Biology; Biology of Aging; Caloric Restriction; Cell Aging; Cells; ChIP-seq; Chromatin; Chromatin Structure; Complex; DNA Sequence Rearrangement; Data; Data Set; Deposition; Dietary Intervention; Elements; Embryo; Epigenetic Process; Extramural Activities; Fibroblasts; Fluorescence Microscopy; Functional RNA; Gene Expression; Gene Expression Profile; Gene Silencing; Genes; Genome; Genomics; Goals; Grant; Heart; Heterochromatin; Histone H2A; Histone H3; Histones; Human; Intervention; Knockout Mice; Laboratories; Lead; Lifting; Lung; Lysine; Macaca mulatta; Mammals; Mentored Research Scientist Development Award; Mentors; Methylation; MicroRNAs; Mitotic; Modification; Mus; Muscle Cells; Myocardium; Organism; PRC1 Protein; Papio; Phenotype; Physiological; Polycomb; Population; Process; Promoter Regions; Proteins; Publications; RNA; Regulation; Regulatory Element; Repression; Research; Research Personnel; Response Elements; Resveratrol; Role; Sequence Analysis; Site; Skeletal Muscle; Small RNA; Structure; Supervision; Techniques; Testing; Tissues; Training; Ubiquitination; Universities; Up-Regulation; Variant; Work; Writing; Yeasts; age related; base; career development; deep sequencing; design; experience; feeding; genome sequencing; genome wide association study; genome-wide; insight; interest; juvenile animal; meetings; normal aging; programs; research study; skills; symposium; transcriptome sequencing

This application for a Mentored Research Scientist Development Award is to facilitate Dr. Jill Kreiling's transition to an independent investigator in the field of aging biology. Her long-term goals include establishing an independent research program focused on advancing our understanding of heterochromatic changes that occur during the natural aging process. To achieve these goals she will follow a structured career development and training plan that includes training practical laboratory techniques and in bioinformatic analyses; university and extramural courses; attending seminars, meetings and conferences; and training in grant writing and laboratory management skills. This plan will be implemented under the supervision of the primary mentor, Dr. John Sedivy, who is an expert in the field of aging biology and has considerable experience with the analysis of genome-wide studies. Dr. Peter Adams, a leader in the field of chromatin biology, will serve as a co-mentor, along with Dr. Robert Reenan who specializes in RNA biology. In addition, Dr. Charles Lawrence will provide guidance with the bioinformatic approach to genome-wide analyses. There is a growing body of evidence that chromatin undergoes reorganization during normal aging. This is accompanied by a corresponding change in gene expression. It is reasonable to expect that these two processes may be connected. However, the epigenetic mechanisms of this extensive rearrangement of the chromatin are virtually unknown. In this application we propose to study the mechanisms that regulate age- associated heterochromatin formation in post-mitotic tissues. Our preliminary data suggest an increase in facultative heterochromatin incorporating the highly repressive histone variant macroH2A in mouse and baboon skeletal muscle. Recent evidence points towards a role of small non-coding RNAs (ncRNAs) in the deposition of repressive heterochromatin marks. The synthesis of many miRNAs (a subclass of ncRNAs) is regulated by Polycomb group (PcG) repression, and our preliminary data suggest a decrease in PcG repression in old animals. We will study the role of ncRNAs in the regulation of age-associated heterochromatin formation in skeletal and cardiac muscle from mice and rhesus monkeys. Specifically we will correlate specific ncRNAs to sites of age associated heterochromatin formation and we will investigate the regulatory elements present in the ncRNA genes. Our hypothesis is: An age-associated reduction in PcG repression leads to activation of certain miRNA genes, whose products trigger age-associated heterochromatin formation at specific sites on the genome. Specific Aim 1: We will begin these studies by identifying the specific chromatin states that correlate with age in post-mitotic tissues. In addition, we will determine if certain dietary interventions (calorie restriction and resveratrol) can delay the onset of this age- associated phenotype. Specific Aim 2: This information will be used to design ChIP-seq assays to determine the regions of the genome susceptible to age-associated heterochromatin formation. The ncRNA populations will be characterized by RNA-seq of the transcriptome to identify ncRNAs subject to age associated increases in expression. The sequences of the ncRNAs showing an age-dependent up-regulation will be correlated with sequences of the genome showing age-associated heterochromatin to determine potential sites of RNA- dependent deposition of silencing marks. Specific Aim 3: Markers of PcG repression will be investigated to determine if there is a decrease in PcG repression with age. The promoter regions of the associated miRNA genes will be analyzed to determine if PcG repressive elements are present that could regulate expression. Finally, we will verify our results with mechanistic studies in cultured human fibroblasts to show that the expression of specific ncRNAs are repressed by PcG regulation in young cells and this repression is lifted in older cells leading to expression of the ncRNA and age-associated heterochromatin formation. Taken together this project will broaden our understanding of the mechanisms and processes involved in the regulation of age- associated heterochromatin formation.

申请指导研究科学家发展奖是为了促进 Jill Kreiling 博士的 转型为衰老生物学领域的独立研究者。她的长期目标包括建立 一个独立的研究项目，专注于增进我们对异色变化的理解 发生在自然老化过程中。为了实现这些目标，她将遵循结构化的职业生涯 开发和培训计划，包括实用实验室技术和生物信息学方面的培训 分析；大学和校外课程；参加研讨会、会议和大会；和培训 拨款写作和实验室管理技能。本计划将在市人大常委会的监督下实施 首席导师John Sedivy博士，是衰老生物学领域的专家，拥有丰富的研究成果 具有全基因组研究分析的经验。 Peter Adams 博士，染色质领域的领军人物 生物学博士将与专门研究 RNA 生物学的 Robert Reenan 博士一起担任联合导师。此外， 查尔斯·劳伦斯博士将为全基因组分析的生物信息学方法提供指导。那里 越来越多的证据表明染色质在正常衰老过程中会发生重组。这是 伴随着基因表达的相应变化。可以合理地预期这两个 进程可以连接。然而，这种广泛的重排的表观遗传机制 染色质几乎是未知的。在本申请中，我们建议研究调节年龄的机制 有丝分裂后组织中相关的异染色质形成。我们的初步数据表明 小鼠和小鼠体内的兼性异染色质结合了高度抑制的组蛋白变体 MacroH2A 狒狒骨骼肌。最近的证据表明小非编码 RNA (ncRNA) 在 抑制性异染色质标记的沉积。许多 miRNA（ncRNA 的一个子类）的合成是 受 Polycomb 组 (PcG) 抑制调节，我们的初步数据表明 PcG 减少 老年动物的压抑。我们将研究 ncRNA 在年龄相关调节中的作用 小鼠和恒河猴骨骼和心肌中异染色质的形成。具体我们将 将特定的 ncRNA 与年龄相关的异染色质形成位点关联起来，我们将研究 ncRNA 基因中存在的调控元件。我们的假设是： PcG 与年龄相关的减少 抑制会导致某些 miRNA 基因的激活，其产物会触发与年龄相关的 基因组上特定位点形成异染色质。具体目标 1：我们将开始这些研究 通过识别与有丝分裂后组织中的年龄相关的特定染色质状态。此外，我们将 确定某些饮食干预措施（热量限制和白藜芦醇）是否可以延缓该年龄的发生- 相关表型。具体目标 2：该信息将用于设计 ChIP-seq 检测以确定 基因组中容易形成与年龄相关的异染色质的区域。 ncRNA 群体 将通过转录组的 RNA-seq 进行表征，以识别受年龄相关增加影响的 ncRNA 在表达中。显示年龄依赖性上调的 ncRNA 序列将与 显示与年龄相关的异染色质的基因组序列，以确定 RNA-的潜在位点 沉默标记的依赖性沉积。具体目标 3：将研究 PcG 抑制标记物 确定 PcG 抑制是否随着年龄的增长而减少。相关 miRNA 的启动子区域 将分析基因以确定是否存在可以调节表达的 PcG 抑制元件。 最后，我们将通过培养人成纤维细胞的机制研究来验证我们的结果，以表明 年轻细胞中特定 ncRNA 的表达受到 PcG 调节的抑制，并且这种抑制在 老年细胞导致 ncRNA 表达和与年龄相关的异染色质形成。合在一起 该项目将加深我们对年龄调节所涉及的机制和过程的理解 相关异染色质形成。