Characterizing new redox roles for protein ubiquitination in human cells

项目总结 人类细胞由于暴露在太阳紫外线辐射下而不断受到氧化应激的影响 水和大气中的污染物。以应对氧化应激的危害，氧化应激可导致细胞 功能障碍和死亡，细胞必须重新编程基因表达，并调整蛋白质生产和 退化。泛素是一种重要的蛋白质修饰物，它控制着许多蛋白质的命运和功能， 并在环境压力下重塑蛋白质组。为了应对氧化压力，数以千计的蛋白质 积累泛素修饰，并参与支持细胞生存的各种功能。我的实验室 发现了一种新的依赖泛素的途径来调节酵母中的蛋白质生产；然而，人们知之甚少 关于这一途径在人类细胞中的重要性和调控。此外，要修改大量的 含有泛素的蛋白质，人类细胞依赖于数百种泛素酶选择性地识别它们的 专门的目标。然而，每种泛素酶对细胞抗逆性的贡献很大程度上是 未知。拟议项目的目的是确定和描述泛素作为大师的作用。 应激反应的调节器。在目标1中，我们将研究局部泛素的分子细节 氧化应激下的堆积，包括何时、为什么和如何发生。在目标2中，我们将调查 使用针对功能域的基因组编辑方法研究细胞对应激反应的不同方面 &gt；700泛素酶。因为氧化应激是各种人类疾病的根本原因，例如 衰老、肿瘤进展和退行性疾病，我们的研究将提供对泛素的新理解 在促进细胞健康方面的作用。明确这些途径的重要性和生理作用 泛素酶将为药物开发提供几种途径，它将使我们了解 细胞抗逆过程中蛋白质泛素化的酶调控基本原理。

PROJECT SUMMARY Human cells are constantly subjected to oxidative stress due to the exposure to solar UV radiation and to pollutants in the water and in the atmosphere. To cope with the harms of oxidative stress that can lead to cellular malfunction and death, cells must reprogram gene expression and adjust the dynamics of protein production and degradation. Ubiquitin is a prominent protein modifier that controls the fate and the function of numerous proteins, and reshapes the proteome during environmental stresses. In response to oxidative stress, thousands of proteins accumulate ubiquitin modification and are involved in a variety of functions that support cellular survival. My lab discovered a new ubiquitin-dependent pathway that regulates protein production in yeast; however little is known about the importance and regulation of this pathway in human cells. In addition, to modify a large number of proteins with ubiquitin, human cells rely on hundreds of ubiquitin enzymes that selectively recognize their dedicated targets. However, the contribution of each ubiquitin enzyme to cellular resistance to stress is largely unknown. The purpose of the proposed project is to identify and characterize the roles of ubiquitin as a master regulator of the stress response. In Aim 1, we will investigate the molecular details of localized ubiquitin accumulation under oxidative stress, including when, why, and how it occurs. In Aim 2, we will investigate different aspects of cellular response to stress using genome editing methodologies targeting functional domains of > 700 ubiquitin enzymes. As oxidative stress is the underlying cause of a variety of human conditions such as aging, tumor progression, and degenerative disease, our research will provide a new understanding of ubiquitin function in the promotion of cellular health. Defining the importance of these pathways and the physiological role of ubiquitin enzymes will provide several avenues for drug development and it will allow us to learn the fundamental principles of the enzymatic regulation of protein ubiquitination during cellular resistance to stress.