National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, 230036, China.
School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China.
BMC Plant Biol. 2022 Mar 5;22(1):98. doi: 10.1186/s12870-022-03490-3.
Hydrogen sulfide (HS) has been proposed to exert anti-oxidative effect under many environmental stresses; however, how it influences oxidative stress remains largely unclear.
Here, we assessed the effects of HS on oxidative stress responses such as salicylic acid (SA)-dependent cell death, which triggered by increased HO availability in Arabidopsis thaliana catalase-deficient mutants cat2 displaying around 20% wild-type catalase activity. HS generation and its producing enzyme -cysteine desulfhydrase (LCD/DES) were found to transient increase in response to intracellular oxidative stress. Although introducing the mutation of des1, an important LCD, into the cat2 background produced little effect, HS fumigation not only rescued the cell death phenotype of cat2 plant, but also attenuated SA accumulation and oxidation of the glutathione pool. Unexpectedly, the activities of major components of ascorbate-glutathione pathway were less affected by the presence of HS treatment, but decreased glycolate oxidase (GOX) in combination with accumulation of glycolate implied HS treatment impacts the cellular redox homeostasis by repressing the GOX-catalyzed reaction likely via altering the major GOX transcript levels.
Our findings reveal a link between HS and peroxisomal HO production that has implications for the understanding of the multifaceted roles of HS in the regulation of oxidative stress responses.
硫化氢 (HS) 在许多环境胁迫下被提出具有抗氧化作用；然而，它如何影响氧化应激在很大程度上仍不清楚。
在这里，我们评估了 HS 对氧化应激反应的影响，例如水杨酸 (SA) 依赖性细胞死亡，这是由拟南芥过氧化氢酶缺陷突变体 cat2 中 HO 可用性增加引发的，cat2 显示约 20%的野生型过氧化氢酶活性。发现 HS 的产生及其产生酶 -半胱氨酸脱硫酶 (LCD/DES) 会在细胞内氧化应激时短暂增加。尽管将重要的 LCD des1 的突变引入 cat2 背景中几乎没有产生影响，但 HS 熏蒸不仅挽救了 cat2 植物的细胞死亡表型，而且还减弱了 SA 的积累和谷胱甘肽池的氧化。出乎意料的是，HS 处理对抗坏血酸-谷胱甘肽途径的主要成分的活性影响较小，但 GOX 与甘醇酸的积累相结合，暗示 HS 处理通过改变主要 GOX 转录本水平来抑制 GOX 催化的反应，从而可能影响细胞的氧化还原稳态。
我们的发现揭示了 HS 与过氧化物酶体 HO 产生之间的联系，这对理解 HS 在调节氧化应激反应中的多方面作用具有重要意义。
