Dynamics and regulation of cysteine S-sulfhydration in cellular functions

细胞功能中半胱氨酸S-硫酸化的动力学和调节

• 批准号: RGPIN-2016-04051
• 负责人: Yang, Guangdong
• 金额: $ 2.26万
• 依托单位: Laurentian University of Sudbury
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=669170
• 关键词: Dynamics; regulation; cysteine; sulfhydration; cellular

Hydrogen sulfide (H2S) is now considered as an endogenous gasotransmitter in a variety of cellular functions and physiological processes. Cystathionine gamma-lyase (CSE) is a major H2S-producing enzyme in mammalian cells. It is proposed that one of the signaling mechanisms of H2S is through the S-sulfhydration of reactive cysteine residues on target proteins by yielding a hydropersulfide moiety (-SSH), with the potential to confer a functional change. S-sulfhydration modulates diverse cellular pathways, including metabolic pathways, protein degradative processes, DNA damage repair, protein interaction and localization, and stress response pathways. This particular redox modification of cysteine by S-sulfhydration has been achieved using proteomics techniques by coupling a specific enrichment strategy (biotin-switch assay and/or tag-switch assay) with high-throughput mass spectrometry (MS) analysis. Our current understanding of the role of S-sulfhydration as a protein signaling modality is still in its infancy. Little is known about the nature of or even necessity for enzymatic mechanisms that may directly add or remove SH groups from cysteine thiols. *** My long-term goal is to elucidate the biological importance of H2S in order to improve our understanding of the regulation of a multitude of cellular functions, and to better train the next generation of researchers in this field. The short-term goal, through this research program, is to determine the biology and chemistry characteristic of cysteine S-sulfhydration with respect to H2S-regulated actin polymerization and cell migration/gap junction in endothelial cells. Mice deficient for CSE showed endothelial dysfunction, suggesting the importance of H2S in maintenance of endothelial integrity. My preliminary data showed that lack of H2S attenuates actin polymerization and endothelial cell migration. In addition, inhibition of thioredoxin 1 (Trx1) strengthened but knockdown of sulfhydryl oxidase expression inhibited actin S-sulfhydration. The objectives of this program are to 1) investigate the effects of the CSE/H2S system in actin polymerization and endothelial cell migration/gap junction, and explore H2S S-sulfhydration of actin-cofilin-profilin complex and the potential cysteine resides; 2), examine the regulation of Trx1 and sulfhydryl oxidase on actin S-sulfhydration/desulfhydation.******* The fact that a very large number of proteins are basally S-sulfhydrated suggests that S-sulfhydration is an important physiologic and pathologic signal. This program may lead to a breakthrough in the understanding of the biological relevance of H2S signaling in humans, and such an understanding will help reveal a novel physiologic posttranslational modification for proteins, which potentially influences a multitude of biological pathways.*********

硫化氢(H_2S)在多种细胞功能和生理过程中被认为是一种内源性气体递质。胱硫醚-伽马裂解酶(CSE)是哺乳动物细胞中一种主要的硫化氢产生酶。有人提出，H_2S的信号机制之一是通过反应性半胱氨酸残基在靶蛋白上的S-硫水化反应产生过硫化物部分(-SSH)，从而可能导致功能改变。S-硫水化作用调节多种细胞途径，包括代谢途径、蛋白质降解过程、DNA损伤修复、蛋白质相互作用和定位以及应激反应途径。利用蛋白质组学技术，通过将特定的浓缩策略(生物素切换分析和/或标签切换分析)与高通量质谱仪(MS)相结合，实现了S-硫酸水合作用对半胱氨酸的这种特殊的氧化还原修饰。我们目前对S-硫水化作为一种蛋白质信号途径的作用的了解还处于初级阶段。人们对直接从半胱氨酸硫醇中添加或移除SH基团的酶机制的性质甚至必要性知之甚少。*我的长期目标是阐明硫化氢的生物学重要性，以便提高我们对多种细胞功能调节的理解，并更好地培训这一领域的下一代研究人员。通过这项研究计划，短期目标是确定半胱氨酸S-硫酸盐水合作用与硫化氢调节的内皮细胞肌动蛋白聚合和细胞迁移/缝隙连接相关的生物学和化学特性。缺乏CSE的小鼠表现出内皮功能障碍，这表明硫化氢在维持内皮完整性方面的重要性。我的初步数据显示，缺乏硫化氢会抑制肌动蛋白聚合和内皮细胞迁移。此外，硫氧还蛋白1(Trx1)的抑制作用增强，但抑制硫氧还蛋白1(Trx1)的表达可抑制肌动蛋白S的硫代水合作用。本项目的目标是：1)研究CSE/H_2S体系在肌动蛋白聚合和内皮细胞迁移/缝隙连接中的作用，探索肌动蛋白-粘附素-Profilin复合体的H_2S-S水合作用和潜在的半胱氨酸残基；2)研究Trx1和硫基氧化酶对肌动蛋白S-硫酸盐水合/脱硫作用的调节。这一计划可能导致对人类硫化氢信号生物学相关性的理解上的突破，这样的理解将有助于揭示一种新的蛋白质的生理学翻译后修饰，它可能影响许多生物途径。