The Gasotransmitter Hydrogen Sulfide Induces Nrf2-Target Genes by Inactivating the Keap1 Ubiquitin Ligase Substrate Adaptor Through Formation of a Disulfide Bond Between Cys-226 and Cys-613
The Gasotransmitter Hydrogen Sulfide Induces Nrf2-Target Genes by Inactivating the Keap1 Ubiquitin Ligase Substrate Adaptor Through Formation of a Disulfide Bond Between Cys-226 and Cys-613
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DOI：
10.1089/ars.2012.4944
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发表时间：
2013-08-01
影响因子：
6.6
通讯作者：
Hayes, John D.
中科院分区：
文献类型：
--
作者：
Hourihan, John M.;Kenna, J. Gerry;Hayes, John D.
目的：信号分子硫化氢（H2S）保护细胞免受氧化应激，并激活NF-E2 p45相关因子2（Nrf 2），这是一种调节抗氧化基因的转录因子。我们试图确定H2S是否需要Nrf 2来保护免受氧化应激，以及H2S对Nrf 2的激活是否涉及Kelch样ECH相关蛋白-1（Keap 1）的拮抗作用，Keap 1是一种氧化还原敏感的泛素连接酶底物接头，在正常稳态条件下抑制Nrf 2。结果：H2S稳定Nrf 2蛋白并通过抗氧化/亲电响应元件诱导Nrf 2靶基因。在小鼠胚胎成纤维细胞中，H2S防止氧化还原循环剂甲萘醌引起的细胞死亡的能力依赖于Nrf 2。此外，Nrf 2调节参与H2S产生（胱硫醚-β-合酶[Cbs]和胱硫醚-γ-裂解酶[Cse]）和H2S降解（硫化物：醌还原酶样[酵母] [Sqrdl]）的鼠基因。我们发现H2S通过抑制Keap 1稳定Nrf 2，这是一种需要底物接头中氨基酸C226和C613共价修饰的事件。H2S上调Nrf 2部分涉及H2 O2的产生，H2 O2通过刺激C226和C613之间分子内二硫键的形成来抑制Keap 1。Keap 1 C226和C613残基也被H2S硫化，这可能需要还原由H2 O2形成的C226-C613二硫键。创新：H2S和H2 O2上调Nrf 2涉及通过C226和C613的修饰使Keap 1失活。结论：H2S对Keap 1的抑制导致Nrf 2介导的细胞保护基因的诱导。Nrf 2控制Cbs、Cse和Sqrdl，表明Nrf 2和H2S之间存在反馈回路。
Aims: The signaling molecule hydrogen sulfide (H2S) protects cells against oxidative stress and activates NF-E2 p45-related factor 2 (Nrf2), a transcription factor that regulates antioxidant genes. We sought to establish whether H2S requires Nrf2 to protect against oxidative stress, and whether activation of Nrf2 by H2S involves antagonism of Kelch-like ECH-associated protein-1 (Keap1), a redox-sensitive ubiquitin ligase substrate adaptor that represses Nrf2 under normal homeostatic conditions. Results: H2S stabilizes Nrf2 protein and induces Nrf2-target genes via an antioxidant-/electrophile-response element. In mouse embryonic fibroblasts, the ability of H2S to protect against cell death caused by the redox-cycling agent menadione is dependent on Nrf2. Moreover, Nrf2 regulates murine genes involved in the production of H2S (Cystathionine-beta-synthase [Cbs] and Cystathionine-gamma-lyase [Cse]) and the degradation of H2S (Sulfide: quinone reductase-like [yeast] [Sqrdl]). We found that H2S stabilizes Nrf2 through inhibition of Keap1, an event that requires covalent modification of amino acids C226 and C613 in the substrate adaptor. Upregulation of Nrf2 by H2S partially involves the production of H2O2, which inhibits Keap1 by stimulating the formation of an intramolecular disulfide bond between C226 and C613. The Keap1 C226 and C613 residues are also S-sulfhydrated by H2S, and this may entail reduction of the C226-C613 disulfide bridge formed by H2O2. Innovation: Upregulation of Nrf2 by H2S and H2O2 involves inactivation of Keap1 through modification of C226 and C613. Conclusion: Inhibition of Keap1 by H2S leads to Nrf2-mediated induction of cytoprotective genes. Nrf2 controls Cbs, Cse, and Sqrdl, suggesting that a feedback loop exists between Nrf2 and H2S.