Regulation of Age-Associated Heterochromatin Formation

年龄相关异染色质形成的调节

• 批准号: 8721818
• 负责人: Jill Kreiling
• 金额: $ 11.63万
• 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/8721818
• 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.

这项指导研究科学家发展奖的申请是为了促进吉尔·克雷林博士的 过渡到衰老生物学领域的独立研究者。她的长期目标包括建立 一个独立的研究计划，旨在促进我们对异质变化的理解， 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 开发和培训计划，包括培训实验室技术和生物信息学 分析；大学和校外课程；参加研讨会，会议和会议；和培训 授予写作和实验室管理技能。该计划将在 主要导师约翰·塞迪维（John Sedivy）博士，他是老化生物学领域的专家 经过全基因组研究分析的经验。彼得·亚当斯（Peter Adams）博士，染色质领域的领导者 生物学将与专门从事RNA生物学的Robert Reenan博士一起担任联合学。此外， 查尔斯·劳伦斯（Charles Lawrence）博士将通过生物信息学分析的生物信息学方法提供指导。那里 是越来越多的证据表明，染色质在正常衰老期间经历重组。这是 伴随着基因表达的相应变化。可以合理地期望这两个 过程可以连接。但是，这种广泛重排的表观遗传机制 染色质实际上是未知的。在此应用中，我们建议研究调节年龄的机制 有效组织中相关的异染色质形成。我们的初步数据表明增加 辅导性异染色质在小鼠和小鼠和 狒狒骨骼肌。最近的证据表明，小型非编码RNA（NCRNA）在 抑制性异染色质标记的沉积。许多miRNA（NCRNA的子类）的合成是 由PolyComb组（PCG）抑制作用，我们的初步数据表明PCG减少 在老动物中镇压。我们将研究NCRNA在与年龄相关的调节中的作用 来自小鼠和恒河猴的骨骼肌和心肌的异染色质形成。特别是我们会的 将特定的NCRNA与年龄相关的异染色质形成相关，我们将研究 NCRNA基因中存在的调节元件。我们的假设是：与年龄相关的PCG减少 抑制导致某些miRNA基因的激活，其产物触发了与年龄相关的 基因组上特定部位的异染色质形成。特定目标1：我们将开始这些研究 通过识别特定的染色质状态，这些染色质与有丝分裂后组织中年龄相关的特定染色质。此外，我们将 确定某些饮食干预措施（卡路里限制和白藜芦醇）是否会延迟该年龄的发作 相关表型。特定目的2：此信息将用于设计芯片序列测定法以确定 基因组的区域易于与年龄相关的异染色质形成。 NCRNA种群 将以转录组的RNA-seq为特征，以识别受年龄相关增加的NCRNA 在表达中。 ncRNA的序列显示出年龄依赖于年龄的上调 基因组的序列显示与年龄相关的异染色质，以确定RNA-的潜在位点 沉默标记的依赖沉积。特定目的3：将研究PCG抑制的标记 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，以确定是否存在可能调节表达的PCG抑制元件。 最后，我们将通过培养的人成纤维细胞中的机械研究来验证我们的结果，以表明 特异性NCRNA的表达受到年轻细胞中PCG调节的抑制 老年细胞导致NCRNA表达和与年龄相关的异染色质形成。一起 该项目将扩大我们对年龄调节所涉及的机制和过程的理解。 相关的异染色质形成。