Chen Xinfang, Huang Dengjing, Man Xiaoling, Li Ailing, Fang Hua, Lu Siting, Yang Di, Liao Weibiao
College of Horticulture, Gansu Agricultural University, 1 Yinmen Village, Anning District, Lanzhou, 730070, People's Republic of China.
Plant Cell Rep. 2025 May 9;44(6):117. doi: 10.1007/s00299-025-03509-7.
Using gene silence and heterologously overexpression, hydrogen sulfide synthesis-related genes l-cysteine desulfhydrase and d-cysteine desulfhydrase have been shown to enhance salt tolerance in tomato seedlings. Hydrogen sulfide (HS) plays an important role in alleviating abiotic stress. L-Cysteine desulfhydrase (LCD) and D-cysteine desulfhydrase (DCD) are two important HS synthesis enzymes. Until now, whether and how SlDCD and SlLCD increase salt tolerance in plant are still unknown. Here, we explored the effects of SlDCD and SlLCD on salt tolerance in tomato seedlings by silencing SlDCD and SlLCD and heterologously overexpressing SlDCD and SlLCD. In tomato seedlings, exogenous sodium hydrosulfide (NaHS, a HS donor) increased salt tolerance while decreasing HS synthesis-related enzyme activity, endogenous HS levels, and HS synthesis-related gene expression. Silencing SlDCD and SlLCD inhibited tomato seedling growth under salt stress, increased relative conductivity, MDA, HO, O, Pro, and carotenoid content, Ci and NPQ. In contrast, it decreased the activity of antioxidant enzymes (POD, SOD, CAT and APX) and the expression of related genes (POD, SOD, CAT and APX), chlorophyll content, photosynthetic parameters (Pn, Gs and Tr) and fluorescence parameters (Fv/Fm, φPSII and qP), while exogenous NaHS considerably mitigated the adverse impacts of salt stress in SlDCD and SlLCD silenced-tomato seedlings. Overexpression of SlDCD and SlLCD in Arabidopsis significantly enhanced plant salt tolerance. Taken together, our results indicate that SlDCD and SlLCD could enhance the antioxidant activity and photosynthesis capacity under salt stress, which results improving salt tolerance in tomato seedlings.
通过基因沉默和异源过表达，已证明硫化氢合成相关基因L-半胱氨酸脱硫酶和D-半胱氨酸脱硫酶可增强番茄幼苗的耐盐性。硫化氢（HS）在缓解非生物胁迫中起重要作用。L-半胱氨酸脱硫酶（LCD）和D-半胱氨酸脱硫酶（DCD）是两种重要的HS合成酶。到目前为止，SlDCD和SlLCD是否以及如何提高植物的耐盐性仍然未知。在这里，我们通过沉默SlDCD和SlLCD以及异源过表达SlDCD和SlLCD来探索它们对番茄幼苗耐盐性的影响。在番茄幼苗中，外源硫氢化钠（NaHS，一种HS供体）提高了耐盐性，同时降低了HS合成相关酶活性、内源HS水平和HS合成相关基因表达。沉默SlDCD和SlLCD会抑制盐胁迫下番茄幼苗的生长，增加相对电导率、丙二醛、过氧化氢、超氧阴离子、脯氨酸和类胡萝卜素含量、胞间二氧化碳浓度和非光化学淬灭。相反，它降低了抗氧化酶（POD、SOD、CAT和APX）的活性以及相关基因（POD、SOD、CAT和APX）的表达、叶绿素含量、光合参数（净光合速率、气孔导度和蒸腾速率）和荧光参数（Fv/Fm、光系统II实际光化学效率和光化学淬灭），而外源NaHS显著减轻了盐胁迫对SlDCD和SlLCD沉默番茄幼苗的不利影响。在拟南芥中过表达SlDCD和SlLCD显著增强了植物的耐盐性。综上所述，我们的结果表明，SlDCD和SlLCD可以在盐胁迫下增强抗氧化活性和光合作用能力，从而提高番茄幼苗的耐盐性。
