The coordination of S-sulfhydration, S-nitrosylation, and phosphorylation of endothelial nitric oxide synthase by hydrogen sulfide
The coordination of S-sulfhydration, S-nitrosylation, and phosphorylation of endothelial nitric oxide synthase by hydrogen sulfide
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DOI：
10.1126/scisignal.2005478
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发表时间：
2014-09-09
影响因子：
7.3
通讯作者：
Wang, Rui
中科院分区：
文献类型：
--
作者：
Altaany, Zaid;Ju, YoungJun;Wang, Rui
由胱硫醚γ-裂解酶（CSE）产生的气体传递剂硫化氢（H2S）通过S-巯基化和潜在的其他机制修饰蛋白质来发出信号。H2S的靶蛋白是内皮型一氧化氮合酶（eNOS），一种产生一氧化氮（NO）的酶，其引起血管舒张。我们研究了硫化氢诱导的S-巯基化是否影响eNOS的S-亚硝基化和磷酸化，以及这些翻译后修饰对eNOS活性变化的功能影响。在体外实验中，不同的NO供体诱导eNOS的S-亚硝基化而不影响其S-巯基化，而H2S供体硫氢化钠（NaHS）降低eNOS的S-亚硝基化。Cys（443）是eNOS中主要的S-巯基化位点，也是可被S-亚硝基化的位点之一。磷酸化增加eNOS活性。尽管表达eNOS的HEK-293细胞暴露于NaHS或血管内皮生长因子（VEGF）触发野生型和C443 G-eNOS的磷酸化，但VEGF不影响eNOS的S-硫氢化，并且不能磷酸化的eNOS突变体仍然是S-硫氢化的。eNOS可以单体或二聚体形式存在于细胞中，但只有eNOS二聚体产生NO。在野生型小鼠中，eNOS蛋白主要是二聚体，而来自CSE敲除（KO）小鼠、S-亚硝基化eNOS和异源表达的C443 G-eNOS的eNOS主要是单体。相应地，CSE-KO内皮细胞中NO的基础产生低于野生型内皮细胞。我们的数据表明，H2S通过诱导eNOS的S-巯基化，促进其磷酸化，抑制其S-亚硝基化和增加eNOS二聚化来增加eNOS活性，而NO通过促进eNOS单体的形成来降低eNOS活性。
The gasotransmitter hydrogen sulfide (H2S), which is generated by cystathionine gamma-lyase (CSE), signals by modifying proteins through S-sulfhydration and potentially other mechanisms. A target protein for H2S is endothelial nitric oxide synthase (eNOS), an enzyme that generates nitric oxide (NO), which causes vasodilation. We investigated whether H2S-induced S-sulfhydration affected the S-nitrosylation and phosphorylation of eNOS and the functional effects of changes in these posttranslational modifications on eNOS activity. In vitro, different NO donors induced the S-nitrosylation of eNOS without affecting its S-sulfhydration, whereas the H2S donor sodium hydrosulfide (NaHS) decreased the S-nitrosylation of eNOS. Cys(443) was the primary S-sulfhydration site in eNOS and was one site that could be S-nitrosylated. Phosphorylation increases eNOS activity. Although exposure of eNOS-expressing HEK-293 cells to NaHS or vascular endothelial growth factor (VEGF) triggered the phosphorylation of wild-type and C443G-eNOS, VEGF did not affect the S-sulfhydration of eNOS and a mutant of eNOS that could not be phosphorylated was still S-sulfhydrated. eNOS can be present in cells in monomeric or dimeric form, but only eNOS dimers produce NO. In wild-type mice, eNOS proteins were predominantly dimerized, whereas eNOS from CSE-knockout (KO) mice, S-nitrosylated eNOS, and heterologously expressed C443G-eNOS was mostly monomeric. Accordingly, basal production of NO was lower in CSE-KO endothelial cells than in wild-type endothelial cells. Our data suggest that H2S increases eNOS activity by inducing the S-sulfhydration of eNOS, promoting its phosphorylation, inhibiting its S-nitrosylation, and increasing eNOS dimerization, whereas NO decreases eNOS activity by promoting the formation of eNOS monomers.