A novel role for human sulfiredoxin in the reversal of glutathionylation
A novel role for human sulfiredoxin in the reversal of glutathionylation
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DOI：
10.1158/0008-5472.can-06-0484
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发表时间：
2006-07-01
期刊：
影响因子：
11.2
通讯作者：
Tew, Kenneth D.
中科院分区：
文献类型：
--
作者：
Findlay, Victoria J.;Townsend, Danyelle M.;Tew, Kenneth D.
通过与谷胱甘肽形成二硫键（谷胱甘肽化）对蛋白质半胱氨酸残基进行修饰是一种可逆的翻译后修饰，对于控制氧化和/或亚硝化应激后的细胞信号转导事件至关重要。在这里，我们表明，人硫氧还蛋白（真核生物中保守的一种小氧化还原蛋白）可以通过催化许多不同蛋白质响应氧化和/或亚硝化应激的去谷胱甘肽作用，充当细胞中氧化还原激活硫醇开关的新型调节剂。肌动蛋白和蛋白酪氨酸磷酸酶 1B 在体外被鉴定为硫氧还蛋白 I (Srx1) 依赖性去谷胱甘肽化的靶标，并通过二维凝胶电泳分析在体内得到证实。此外，我们还发现 Srx1 依赖性去谷胱甘肽作用通过恢复磷酸酶活性而具有功能相关性。人硫氧还蛋白含有一个在所有家族成员中都是保守的半胱氨酸残基 (Cys(99))。半胱氨酸残基的突变抑制去谷胱甘肽化，但不影响其结合细胞内蛋白质的能力。此外，硫氧还蛋白在反应过程中不是GS(-)部分的受体分子。使用二维凝胶电泳，我们鉴定了体内多个蛋白质靶标，这些蛋白质靶标在氧化和/或亚硝化应激后被硫氧还蛋白去谷胱甘肽化。硫氧还蛋白的这种新型去谷胱甘肽功能表明它在氧化还原控制中发挥着核心作用，对细胞信号传导具有潜在影响。
Modification of protein cysteine residues by disulfide formation with glutathione (glutathionylation) is a reversible posttranslational modification of critical importance in controlling cell signaling events following oxidative and/or nitrosative stress. Here, we show that human sulfiredoxin, a small redox protein conserved in eukaryotes, can act as a novel regulator of the redox-activated thiol switch in cells by catalyzing deglutathionylation of a number of distinct proteins in response to oxidative and/or nitrosative stress. Actin and protein tyrosine phosphatase 1B were identified in vitro as targets of sulfiredoxin I (Srx1)-dependent deglutathionylation and confirmed in vivo by two-dimensional gel electrophoresis analysis. In addition, we show that Srx1-dependent deglutathionylation is functionally relevant through restoration of phosphatase activity. Human sulfiredoxin contains one cysteine residue (Cys(99)) that is conserved in all family members. Mutation of the cysteine residue inhibits deglutathionylation but did not affect its capacity to bind intracellular proteins. Furthermore, sulfiredoxin is not an acceptor molecule for the GS(-) moiety during the reaction process. Using two-dimensional gel electrophoresis, we identified multiple protein targets in vivo that are deglutathionylated by sulfiredoxin following oxidative and/or nitrosative stress. This novel deglutathionylation function of sulfiredoxin suggests it has a central role in redox control with potential implications in cell signaling.