Epigenetic Reprogramming of Cellular Age

细胞年龄的表观遗传重编程

• 批准号: 10516941
• 负责人: THOMAS A. RANDO
• 金额: $ 45.93万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10516941
• 关键词: ATAC-seq; Acceleration; Address; Affect; Age; Aging; Biological; Biological Assay; Blood; Cell Aging; Cell Communication; Cells; ChIP-seq; Characteristics; Complement; DNA Methylation; Data; Enzymes; Epigenetic Process; Exhibits; Exposure to; Generations; Genetic; Genetic Transcription; Genetic study; Goals; Heterochromatin; Histones; Homeostasis; In Vitro; Intervention; Knock-out; Laboratory Animals; Liver; Longevity; Lysine; Mediating; Mediator of activation protein; Methylation; Methyltransferase; Molecular; Molecular Mechanisms of Action; Molecular Profiling; Mus; Muscle; Muscle Cells; Muscle satellite cell; Nucleosomes; Parabiosis; Pathway interactions; Pharmacology; Pharmacology Study; Phenotype; Plasma; Population; Process; Protocols documentation; Publishing; Rejuvenation; Reporting; Role; Serum; System; Testing; Tissues; age effect; aged; base; cell age; cell growth regulation; demethylation; epigenome; experimental study; histone demethylase; histone methyltransferase; histone modification; in vitro Model; in vivo; in vivo evaluation; induced pluripotent stem cell; inhibitor; interest; methylation pattern; muscle aging; repaired; response; restoration; single-cell RNA sequencing; stem cell aging; tool; transcriptome

PROJECT SUMMARY Current ideas that systemic factors regulate the aging of cells and tissues, in terms of both promoting and reversing the aging process, have emerged from studies of heterochronic parabiosis (HP) and heterochronic blood exchange (HBE) protocols. Our lab performed the first HP studies in order to assess cellular aging and rejuvenation as it relates to tissue homeostasis and repair and in terms of molecular determinants of cellular age. Initially, we focused changes in muscle stem cells (MuSCs), but we and others later explored these phenotypic changes in many different cell populations. Since then, we have explored the molecular mechanisms by which systemic factors might influence the aging process. Based on numerous lines of evidence, we have hypothesized that the alteration in cellular aging features is due to a form of epigenetic reprogramming that is akin to that which occurs during induced pluripotent stem cell generation but without the loss of cellular differentiation. A general feature of cellular aging is the loss of heterochromatin and subsequent dysregulation of transcriptional stability. Heterochromatin is prominently associated with specific histone modifications, most notably by di- and tri-methylation of lysine 9 on histone 3 (H3K9me2 and H3K9me3, respectively). In Preliminary Studies, we have shown the H3K9me3 and heterochromatin can be regulated in MuSCs, with loss of both leading to features seen in aging cells. Based on these data and related published findings, the primary hypothesis of this proposal is that a primary mediator of HP and HBE transposition of aging phenotypes to young and old cells is the regulation of the cellular epigenome, and with a specific focus on H3K9 methylation and heterochromatin formation. To test this hypothesis, this proposal is divided into three Specific Aims. Aim 1: To assess the transcriptional and epigenetic signature of MuSCs in response to HP. We will establish HP and control pairs, and we will assess the MuSC molecular signatures compared to control mice in assays of the transcriptome and the epigenome. Aim 2: To examine the epigenetic mechanisms underlying the transposition of aging phenotypes in MuSCs. Using genetic and pharmacologic tools, we will modulate H3K9 methylation in young and old MuSCs exposed to young or old serum in vitro. We will test for the effect of changes in H3K9 methylation on the phenotypic changes of MuSCs previously described in response to heterochronic serum exposure. Aim 3: To test in vivo for the essential roles of H3K9 methyltransferase and demethylase activities in mediating the effects of HP on MuSCs. We will use genetic and pharmacologic tools to modulate H3K9 methylation in MuSCs in vivo. We will assess epigenetic and heterochromatin status, as well as the functional changes in MuSCs in response to HP. Together, these studies will elucidate molecular mechanisms of epigenetic programming of age in response to HP and HBE.

项目总结 目前的观点认为，系统性因素通过促进和促进细胞和组织的衰老来调节细胞和组织的衰老 逆转衰老过程的研究出现了异慢性异型共生(HP)和异型共生 血液交换(HBE)协议。我们的实验室进行了第一次惠普研究，以评估细胞老化和 返老还童，因为它与组织的动态平衡和修复以及细胞年龄的分子决定因素有关。 最初，我们关注肌肉干细胞(MuSCs)的变化，但后来我们和其他人探索了这些表型 许多不同细胞群的变化。从那时起，我们一直在探索 系统性因素可能影响衰老过程。基于大量证据，我们假设 细胞衰老特征的改变是由于一种形式的表观遗传重新编程，类似于 发生在诱导多能干细胞生成过程中，但不会丧失细胞分化。 细胞衰老的一个普遍特征是异染色质的丢失和随之而来的 转录稳定性。异染色质与特定的组蛋白修饰显著相关，大多数 特别是通过组蛋白3(分别为H3K9me2和H3K9me3)上赖氨酸9的二甲基化和三甲基化。在预赛中 研究表明，H3K9me3和异染色质在MUSCs中可以调节，但两者都失去了领先的 与衰老细胞中的特征有关。根据这些数据和相关发表的研究结果，初步假设 这一建议是Hp和HBE的主要介体将衰老表型转位到年轻和老年细胞 是对细胞表观基因组的调节，并特别关注H3K9甲基化和异染色质 队形。 为了检验这一假设，这一提议被分为三个具体目标。目标1：评估转录 和MUSCs对幽门螺杆菌的表观遗传特征。我们将建立HP和CONTROL对，我们将评估 在转录组和表观基因组分析中，MUSC的分子特征与对照小鼠进行了比较。 目的：研究骨髓间充质干细胞衰老表型易位的表观遗传学机制。 利用遗传和药理学工具，我们将调节暴露在年轻和老年MSC中的H3K9甲基化 对年轻或老年血清的体外研究。我们将测试H3K9甲基化变化对表型的影响 上述MUSCs在异种血清暴露下的变化。目标3：体内试验 H3K9甲基转移酶和去甲基酶活性在幽门螺杆菌感染中的重要作用 多用途干细胞。我们将使用遗传和药理学工具在体内调节MUSCs中的H3K9甲基化。我们会 评估表观遗传学和异染色质状态，以及幽门螺杆菌感染后MUSCs的功能变化。 总之，这些研究将阐明AGE的表观遗传编程响应的分子机制 惠普和HBE。