Multilevel Regulation of 2-Cys Peroxiredoxin Reaction Cycle by S-Nitrosylation
Multilevel Regulation of 2-Cys Peroxiredoxin Reaction Cycle by S-Nitrosylation
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DOI：
10.1074/jbc.m112.433755
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发表时间：
2013-04-19
影响因子：
4.8
通讯作者：
Benhar, Moran
中科院分区：
文献类型：
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作者：
Engelman, Rotem;Weisman-Shomer, Pnina;Benhar, Moran
S-亚硝基硫醇（S-Nitrosothiols，SNOs）是由一氧化氮（nitric oxide，NO）介导的S-亚硝基化反应和过氧化氢（hydrogen peroxide，H2 O2）形成的一种重要的活性氧，参与多种生理和病理过程。最近的研究表明，SNO和H2 O2的细胞作用和代谢涉及重叠的基于硫醇的机制，但这些反应性物质如何影响彼此的命运和功能还没有很好的理解。在这项研究中，我们研究了NO/SNO可能会影响哺乳动物过氧化物酶-1（Prx 1）的氧化还原循环，Prx 1是2-Cys Prxs的代表，是一组硫氧还蛋白（Trx）依赖性过氧化物酶。我们发现，无论是在无细胞系统中，在细胞中，NO/SNO捐助者，如S-亚硝基半胱氨酸和S-亚硝基谷胱甘肽容易诱导的S-亚硝基化的Prx 1，造成结构和功能的改变。特别是，亚硝基化促进二硫键的形成，涉及对催化半胱氨酸（Cys-52和Cys-173）和破坏的Prx 1的寡聚体结构，导致过氧化物酶活性的损失。一个非常有效的抑制过氧化物酶催化反应的NO/SNO被认为是在采用耦合Prx-Trx系统的测定。在这种情况下，S-亚硝基半胱氨酸（10 μ M）有效地阻止了Trx介导的再生氧化Prx 1。这种效果似乎是由于S-亚硝基半胱氨酸和Prx 1的Trx系统和直接调制的Trx还原酶活性的S-亚硝基半胱氨酸之间的竞争。我们的研究结果，NO/SNO的目标Prx和Trx还原酶可能有影响理解亚硝基化对细胞氧化还原稳态的影响。
S-Nitrosothiols (SNOs), formed by nitric oxide (NO)-mediated S-nitrosylation, and hydrogen peroxide (H2O2), a prominent reactive oxygen species, are implicated in diverse physiological and pathological processes. Recent research has shown that the cellular action and metabolism of SNOs and H2O2 involve overlapping, thiol-based mechanisms, but how these reactive species may affect each other's fate and function is not well understood. In this study we investigated how NO/SNO may affect the redox cycle of mammalian peroxiredoxin-1 (Prx1), a representative of the 2-Cys Prxs, a group of thioredoxin (Trx)-dependent peroxidases. We found that, both in a cell-free system and in cells, NO/SNO donors such as S-nitrosocysteine and S-nitrosoglutathione readily induced the S-nitrosylation of Prx1, causing structural and functional alterations. In particular, nitrosylation promoted disulfide formation involving the pair of catalytic cysteines (Cys-52 and Cys-173) and disrupted the oligomeric structure of Prx1, leading to loss of peroxidase activity. A highly potent inhibition of the peroxidase catalytic reaction by NO/SNO was seen in assays employing the coupled Prx-Trx system. In this setting, S-nitrosocysteine (10 mu M) effectively blocked the Trx-mediated regeneration of oxidized Prx1. This effect appeared to be due to both competition between S-nitrosocysteine and Prx1 for the Trx system and direct modulation by S-nitrosocysteine of Trx reductase activity. Our findings that NO/SNO target both Prx and Trx reductase may have implications for understanding the impact of nitrosylation on cellular redox homeostasis.