Hydrogen sulfide (H₂S) is an important gaseous signal molecule which participates in various abiotic stress responses. However, the underlying mechanism of H₂S associated salt tolerance remains elusive. In this study, sodium hydrosulfide (NaHS, donor of H₂S) was used to investigate the protective role of H₂S against salt stress at the biochemical and proteomic levels. Antioxidant activity and differentially expressed proteins (DEPs) of rice seedlings treated by NaCl or/and exogenous H₂S were investigated by the methods of biochemical approaches and comparative proteomic analysis. The protein-protein interaction (PPI) analysis was used for understanding the interaction networks of stress responsive proteins. In addition, relative mRNA levels of eight selected identified DEPs were analyzed by quantitative real-time PCR. The result showed that H₂S alleviated oxidative damage caused by salt stress in rice seedling. The activities of some antioxidant enzymes and glutathione metabolism were mediated by H₂S under salt stress. Proteomics analyses demonstrated that NaHS regulated antioxidant related proteins abundances and affected related enzyme activities under salt stress. Proteins related to light reaction system (PsbQ domain protein, plastocyanin oxidoreductase iron-sulfur protein), Calvin cycle (phosphoglycerate kinase, sedoheptulose-1,7-bisphosphatase precursor, ribulose-1,5-bisphosphate carboxylase/oxygenase) and chlorophyll biosynthesis (glutamate-1-semialdehyde 2,1-aminomutase, coproporphyrinogen III oxidase) are important for NaHS against salt stress. ATP synthesis related proteins, malate dehydrogenase and 2, 3-bisphosphoglycerate-independent phosphoglycerate mutase were up-regulated by NaHS under salt stress. Protein metabolism related proteins and cell structure related proteins were recovered or up-regulated by NaHS under salt stress. The PPI analysis further unraveled a complicated regulation network among above biological processes to enhance the tolerance of rice seedling to salt stress under H₂S treatment. Overall, our results demonstrated that H₂S takes protective roles in salt tolerance by mitigating oxidative stress, recovering photosynthetic capacity, improving primary and energy metabolism, strengthening protein metabolism and consolidating cell structure in rice seedlings.

硫化氢（H ₂ S）是一种重要的气体信号分子，参与各种非生物胁迫反应。然而，H ₂ S 相关耐盐性的潜在机制仍然难以捉摸。在本研究中，硫氢化钠（NaHS，H ₂ S 的供体）被用于研究 H ₂ S 在生化和蛋白质组学水平上对盐胁迫的保护作用。NaCl或/和外源H ₂处理的水稻幼苗的抗氧化活性和差异表达蛋白（DEPs）通过生化方法和比较蛋白质组学分析方法对S进行了研究。蛋白质-蛋白质相互作用 (PPI) 分析用于了解应激反应蛋白的相互作用网络。此外，通过定量实时 PCR 分析了八种选定的已鉴定 DEP 的相对 mRNA 水平。结果表明，H ₂ S减轻了盐胁迫对水稻幼苗的氧化损伤。一些抗氧化酶的活性和谷胱甘肽代谢是由 H ₂介导的S 在盐胁迫下。蛋白质组学分析表明，在盐胁迫下，NaHS 调节抗氧化相关蛋白质的丰度并影响相关酶的活性。与光反应系统（PsbQ 结构域蛋白、质体蓝素氧化还原酶铁硫蛋白）、卡尔文循环（磷酸甘油酸激酶、sedoheptulose-1,7-二磷酸酶前体、核酮糖-1,5-二磷酸羧化酶/加氧酶）和叶绿素生物合成（谷氨酸）相关的蛋白质-1-半醛 2,1-氨基变位酶、粪卟啉原 III 氧化酶）对于 NaHS 对抗盐胁迫很重要。ATP 合成相关蛋白、苹果酸脱氢酶和 2, 3-二磷酸甘油酸非依赖性磷酸甘油酸变位酶在盐胁迫下被 NaHS 上调。盐胁迫下NaHS恢复或上调蛋白质代谢相关蛋白和细胞结构相关蛋白。₂ S处理。总体而言，我们的研究结果表明，H ₂ S 通过减轻氧化应激、恢复光合能力、改善初级和能量代谢、加强蛋白质代谢和巩固水稻幼苗的细胞结构，在耐盐性中发挥保护作用。