Are the pathways that protect tissues from mechanical stress lost in ageing?

保护组织免受机械应力的途径是否会因衰老而丧失？

• 批准号: 2282703
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2282703
• 关键词: pathways; protect; tissues; mechanical; stress

The defining qualities of our cells - their physical features and function - can be determined by their surroundings, but the tissue environment can be demanding. Just as our muscles regenerate and are conditioned by exercise to maintain health, our cells have developed mechanisms to protect against damage induced by mechanical stress. A fundamental response to stress is the production of chaperone proteins within our cells. These molecular machines act to limit and reverse damage by refolding the proteins unwound by stress back into functional structures. However, these mechanisms are thought to deteriorate as we age. This loss of function may be compounded by other factors affecting ageing tissue. The extracellular matrix - the material in which cells are embedded - may stiffen and become fibrotic in ageing tissue, changing the ways that tissue-resident cells experience mechanical stresses. A knowledge of the pathways that enable cells to sense and respond to physical signals is therefore key to understanding the ageing process. This project will look at how senescent cells, used as a model of ageing, respond to periods of cyclic straining in two- and three-dimensional environments. It will build on new and exciting findings from the Swift laboratory: (i) that senescent cells lose their ability to 'feel' and respond to the mechanical properties of their environments; (ii) that senescent cells also lose their ability to express protective chaperone proteins when faced with stress; and (iii) that regulation of mechano-sensitivity and chaperone expression are integral to the strain response in healthy (i.e. nonsenescent) cells. The responses of senescent cells will be compared to control cells using combinations of: microscopy, to characterise structural and morphological changes within cells; mass spectrometry proteomics, to identify, in an unbiased way, the stress-regulation pathways abrogated in senescence; and RNA-Seq transcriptomics to establish complete signalling pathways. We will also look for evidence of compromised cellular integrity, such as the accruement of DNA damage. Important pathways will be investigated in more detail by knocking down key proteins, or by expressing proteins in senescent cells to restore function. This 'Underpinning Bioscience' project will take a multidisciplinary approach to deliver fundamental insight into the ageing process in mechanically loaded tissues. It will aim to build a holistic picture of how cells function, from a molecular level to their integration within three-dimensional environments that replicate active, living tissues. The project will deliver on the BBSRC's ENWW remit in two ways: Firstly, it will build on the Swift lab's experience in integrating complex '-omics' datasets with imaging and molecular biology methods to give a complete understanding of the underlying biology. The student will analyse samples using mass spectrometry proteomics and RNA-Seq (with support from Core Facilities), and will interpret the data with assistance from established collaborators with backgrounds in bioinformatics and statistics. Secondly, it is very much an interdisciplinary project that combines methods in molecular and cell biology with biophysics to build an improved understanding of the physiological ageing process. The student will have access to a broad range of tools in biology, physics and engineering laboratories. They will learn how to solve problems in novel ways and will be well placed to take advantage of the exciting and underexploited areas of overlap between disciplines.

我们细胞的定义品质——它们的物理特征和功能——可以由它们的周围环境决定，但组织环境可能要求很高。正如我们的肌肉会再生并通过锻炼来保持健康一样，我们的细胞也发展出了机制来防止机械应力引起的损伤。对压力的基本反应是细胞内伴侣蛋白的产生。这些分子机器通过将因压力而解开的蛋白质重新折叠回功能结构来限制和逆转损伤。然而，这些机制被认为会随着年龄的增长而恶化。这种功能丧失可能会因影响老化组织的其他因素而加剧。细胞外基质（细胞嵌入的材料）可能会在老化组织中变硬并纤维化，从而改变组织驻留细胞经历机械应力的方式。因此，了解细胞感知和响应物理信号的途径是理解衰老过程的关键。 该项目将研究用作衰老模型的衰老细胞如何对二维和三维环境中的循环应变周期做出反应。它将建立在斯威夫特实验室令人兴奋的新发现的基础上：（i）衰老细胞失去“感觉”和对其环境的机械特性做出反应的能力； (ii) 衰老细胞在面临压力时也会失去表达保护性伴侣蛋白的能力； (iii) 机械敏感性和伴侣表达的调节对于健康（即非衰老）细胞的应变反应是不可或缺的。将使用以下组合将衰老细胞的反应与对照细胞进行比较： 显微镜，以表征细胞内的结构和形态变化；质谱蛋白质组学，以公正的方式识别衰老过程中消除的压力调节途径；和RNA-Seq转录组学以建立完整的信号通路。我们还将寻找细胞完整性受损的证据，例如 DNA 损伤的累积。通过敲除关键蛋白质或通过在衰老细胞中表达蛋白质来恢复功能，将更详细地研究重要途径。 这个“基础生物科学”项目将采用多学科方法来提供对机械负载组织老化过程的基本见解。其目标是全面了解细胞如何发挥作用，从分子水平到细胞在复制活性活体组织的三维环境中的整合。该项目将以两种方式履行 BBSRC 的 ENWW 职责：首先，它将建立在 Swift 实验室将复杂的“组学”数据集与成像和分子生物学方法相结合的经验基础上，以全面了解基础生物学。学生将使用质谱蛋白质组学和 RNA-Seq 分析样本（在核心设施的支持下），并将在具有生物信息学和统计学背景的既定合作者的帮助下解释数据。其次，它在很大程度上是一个跨学科项目，将分子和细胞生物学方法与生物物理学相结合，以加深对生理衰老过程的理解。学生将能够使用生物学、物理和工程实验室的各种工具。他们将学习如何以新颖的方式解决问题，并将充分利用学科之间令人兴奋且尚未充分开发的重叠领域。