CAREER: Understanding the Interdependence of the Microenvironment and Nuclear Organization in Stem Cell Aging

职业：了解干细胞衰老过程中微环境和核组织的相互依赖性

• 批准号: 2045977
• 负责人: Carlos Aguilar
• 金额: $ 51.21万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045977&HistoricalAwards=false
• 关键词: CAREER; Understanding; Interdependence; Microenvironment; Nuclear

The dramatic increase in the elderly population presents new challenges for our society, and a critical effector of healthy lifespan is functioning skeletal muscle. Despite the significant personal and societal costs of age-related muscle atrophy and weakness, only modest progress has been made in understanding this degenerative process. One critical factor is a reduction in number and function of adult stem cells with aging. Hence, a mechanistic understanding of how muscle stem cells become dysfunctional in old age is needed. The research objective of this Faculty Early Career Development (CAREER) project is to establish systems to study how stem cells receive and store information in their nuclei (which contain genetic information and controls and regulates cell activities) during aging. The outcome will be enhanced understanding of the stem cell aging process in a unified and controllable manner. The primary educational objective of this project is to develop a series of stories that focus on introducing concepts of stem cells and genomics to under-represented minority (URM) students in K-3. These stories aim to increase scientific literacy and reduce the language barrier for URM students to engage with STEM principles and genomics at an early age, and positively portray underrepresented Minorities using Integrative Genomics, Human stem cells, and TechnologY (MIGHTY).The investigator's long-term research goal is to develop and optimize technologies and therapeutics that prevent or delay age-related declines in skeletal muscle function that occur in the elderly population. A known critical contributor of sarcopenia (age-induced skeletal muscle wasting) is muscle stem cell dysfunction, which is regulated by the packaging of the genome in the nucleus. Thus, in keeping with the long-term goal, this NSF CAREER project aims to elucidate the sensitive relationship between nuclear organization and the stem cell microenvironment in aging using in situ genome editing, microfluidics, biomaterials and integrative genomic assays. The Research Plan is organized under two objectives. The FIRST Objective is to demonstrate that muscle stem cell dysfunction observed in aging is driven by 3D genome misfolding. An in-situ genome editing (CRISPR-Cas9) system in muscle stem cells will be used to manipulate heterochromatin and hierarchical nuclear organization. High-resolution 3D imaging coupled with epigenomic mapping will be used to contrast the effects of these perturbations with muscle stem cells isolated from different stages of life (youth, middle-age and old age). Successful completion of these experiments will demonstrate how intrinsic alterations through genome folding engender stem cell dysfunction and remodeling of the microenvironment as well as expose the relative susceptibility of each part of the genome to deleterious changes that occur in aging. The SECOND Objective is to establish that the aberrant extracellular matrix produced during aging engenders chromatin defects that regulate muscle stem cell expansion. Envelope muscle stem cells on myofibers with engineered biomaterials that replicate aspects of an aging endomysium will be used to assess the effect on chromatin architecture and stem cell expansion. Extracellular matrix density, elastic moduli, composition and structure surrounding muscle stem cells will be varied to determine how different types of modifications converge onto nuclear organization and impact clonal dynamics. Successful completion of these experiments will reveal how muscle stem cells transduce alterations in their microenvironment into chromatin remodeling during aging and how these adjustments drive variations in proliferative behavior. The ability to make meaningful connections between these innovative engineering systems and critically important biological process in aging will facilitate construction of a molecular-scale, integrated understanding of the stem cell aging process that can help advance therapeutics, and fulfill knowledge gaps.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

老年人口的急剧增长给我们的社会带来了新的挑战，健康寿命的关键效应因素正在发挥骨骼肌的作用。尽管与年龄相关的肌肉萎缩和弱点的个人和社会成本巨大，但在理解这一退化过程时只取得了适度的进步。一个关键因素是衰老成年干细胞的数量和功能减少。 因此，需要对肌肉干细胞在老年中如何功能失调的机械理解。该教师早期职业发展（职业）项目的研究目标是建立系统，以研究干细胞在衰老期间如何在其核中接收和存储信息（其中包含遗传信息和控制并调节细胞活动）。结果将是以统一和可控制的方式增强对干细胞老化过程的理解。该项目的主要教育目标是开发一系列故事，这些故事着重于将干细胞和基因组学概念引入K-3中代表性不足的少数群体（URM）学生。 These stories aim to increase scientific literacy and reduce the language barrier for URM students to engage with STEM principles and genomics at an early age, and positively portray underrepresented Minorities using Integrative Genomics, Human stem cells, and TechnologY (MIGHTY).The investigator's long-term research goal is to develop and optimize technologies and therapeutics that prevent or delay age-related declines in skeletal muscle function that occur in the elderly population.肌肉减少症（年龄引起的骨骼肌浪费）的已知关键因素是肌肉干细胞功能障碍，该功能受基因组在细胞核中的包装进行调节。 因此，为了与长期目标保持一致，该NSF职业项目旨在阐明使用原位基因组编辑，微流体，生物材料和综合基因组学分析的核组织与干细胞微环境之间的敏感关系。研究计划是在两个目标下组织的。 第一个目的是证明衰老中观察到的肌肉干细胞功能障碍是由3D基因组错误折叠驱动的。肌肉干细胞中的原位基因组编辑（CRISPR-CAS9）系统将用于操纵异染色质和分层核组织。高分辨率3D成像与表观基因组映射相结合将用于对比这些扰动的作用与从不同阶段（青年，中年和老年）分离的肌肉干细胞的作用。这些实验的成功完成将证明如何通过基因组折叠导致干细胞功能障碍和微环境的重塑以及揭示基因组每个部分对衰老发生有害变化的相对敏感性的固有改变。第二个目标是确定在老化产生的染色质缺陷中产生的异常细胞外基质会调节肌肉干细胞膨胀。带有工程生物材料的肌纤维上的包膜肌肉干细胞复制衰老内体的各个方面，用于评估对染色质结构和干细胞膨胀的影响。细胞外基质密度，弹性模量，组成和肌肉干细胞周围的结构将变化，以确定不同类型的修饰如何融合到核组织上并影响克隆动力学。这些实验的成功完成将揭示肌肉干细胞在衰老期间如何转化其微环境中的改变其微环境中的染色质重塑，以及这些调整如何驱动增殖行为的变化。在衰老中建立有意义的联系和至关重要的生物学过程之间建立有意义的联系的能力将有助于构建分子规模的，对干细胞老化过程的综合理解，这些过程可以帮助提高治疗障碍，并实现知识差距。该奖项反映了NSF的法定任务，并通过评估基金会的范围来反映出支持者的支持者，并通过基金会的范围进行了评估。