AGING EFFECT ON PROTEIN S THIOLATION/DETHIOLATION

我们的长期目标是了解这种蛋白质的功能 保护反应蛋白巯基的抗氧化系统 防止氧化损伤，即蛋白质S-硫基化/去硫化 保护系统。此应用程序是一个为期一年的试点项目，以 研究蛋白质S-硫代/去硫基化在血管紧张素转换酶中的作用 衰老动物模型。我们将i)确定衰老是否导致 大鼠蛋白质S-硫代化增加，识别个体 用一种新提出的方法修饰蛋白质，以及 不可逆修饰形式的碳酸酐酶III是一种 S保护不足的后果--硫代化/去硫代化； 2)确定脱硫醇系统，即谷氧还蛋白 和硫氧还蛋白，由于老化而效果较差；以及 3)开发一种产生谷胱甘肽抗体的方法，该抗体可以 用于检测蛋白质结合的谷胱甘肽，即S-谷胱甘肽 蛋白质，在未来的实验中。这些实验是我们第一次 蛋白质抗氧化系统功能关系的探讨 (S-硫代化/去硫代化)改变信号转导，以及 衰老动物模型中的基因转录。该提案的基础是 关于最近一篇关于碳的S-谷胱甘肽增加的报道 老年大鼠肝脏中的脱水酶III。这一独特的结果 这表明蛋白质抗氧化系统在 年龄较大的动物，可能导致不可逆转的改变 这些蛋白质的(氧化)以及增加的S-硫代化 一些重要的半胱氨酸蛋白质。既然我们建议 脂肪，ADP-核糖化，半胱氨酸- 细胞凋亡中介导的蛋白分解和氧化还原控制 转录均受S-硫代化/去硫代化保护 抗氧化剂系统，其保护作用的任何丧失 对老年人正常的细胞功能肯定是有害的 动物。这些实验描述了评估两种蛋白质S- 老年动物的硫代化和不可逆氧化。

Our long term goal is to understand the function of the protein antioxidant system that protects reactive protein sulfhydryl groups from oxidative damage, i.e, the protein S-thiolation/ dethiolation protection system. This application is a one year pilot project to investigate the role of protein S-thiolation/dethiolation in an aging animal model. We will I) determine whether aging causes increased protein S-thiolation in rats, identifying individual modified proteins by a newly proposed method, and whether irreversibly modified forms of carbonic anhydrase III are a consequence of inadequate protection by S-thiolation/dethiolation; 2) determine whether the dethiolation system, i.e., glutaredoxin and thioredoxin, is less effective as a consequence of aging; and 3) develop a method to produce an antibody to glutathione that can be used to detect protein-bound glutathione, i.e., S-glutathiolated proteins, in future experiments. These experiments are our first attempt to relate the function of the protein antioxidant system (S-thiolation/dethiolation) to altered signal transduction, and gene transcription in an aging animal model. The proposal is based on a recent report of increased S-glutathiolation of carbonic anhydrase III in the liver of older rats. This unique result suggests that the protein antioxidant system is less effective in older animals, potentially leading to irreversible modification (oxidation) of these proteins as well as increased S-thiolation of a number o important protein cysteines. Since we propose that the cysteines required for lipidation, ADP-ribosylation, cysteine- mediated proteolysis in apoptosis, and redox control of transcription are all protected by the S-thiolation/dethiolation antioxidant system, any loss of the protective role it performs would certainly be detrimental to proper cell functions in aged animals. The experiments describe methods to assess both protein S- thiolation and irreversible oxidation in older animals.