Wang Lanlan, Yao Yuxi, Wang Jiayu, Cui Jinghui, Wang Xuhao, Li Xuemei, Li Yueying, Ma Lianju
College of Life Science, Shenyang Normal University, Shenyang, Liaoning 110034, China.
Ecotoxicol Environ Saf. 2023 Feb;251:114515. doi: 10.1016/j.ecoenv.2023.114515. Epub 2023 Jan 9.
Rice seedlings were exposed to two CO concentrations (400 ± 20 and 800 ± 20 μmol mol) and three PbNO concentrations (0, 50 and 100 µmol L) for 10 days to explore the regulatory mechanisms of elevated CO for Pb stress resistance. Electrical conductivity, MDA content, SOD, POD, CAT activities and metabolomics changes were studied. Results showed that: Pb stress damaged cell membrane system, electrical conductivity and MDA content increased 49.34 % and 73.27 %, respectively, and some antioxidant enzymes activities increased. Sugar, polyol, amino acid metabolism and fatty acid β-oxidation were all enhanced to improve osmotic adjustments, maintain cell membrane stability, supply energy, nitrogen assimilates and antioxidant capacity; Under composite treatments, cell membrane damage was reduced, activities of protective enzymes increased compared with only Pb stress, POD activity increased the most (49.14 %) under severe Pb composite treatment. High CO caused the enhance of cells antioxidant capacity, TCA cycle intermediate products contents and fatty acid desaturation under mild Pb stress. Many sugars, polyols and amino acids contents were increased as osmotic regulatory substances by high CO under severe Pb stress; Secondary metabolites played an important role under Pb stress and composite treatments. The object of this study is to provide a possible molecular mechanism of rice response to Pb stress under high CO in the future.
将水稻幼苗暴露于两种CO浓度（400±20和800±20 μmol mol）和三种PbNO浓度（0、50和100 µmol L）下10天，以探究高浓度CO对铅胁迫抗性的调控机制。研究了电导率、丙二醛（MDA）含量、超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）活性以及代谢组学变化。结果表明：铅胁迫破坏了细胞膜系统，电导率和MDA含量分别增加了49.34%和73.27%，一些抗氧化酶活性增加。糖、多元醇、氨基酸代谢以及脂肪酸β-氧化均增强，以改善渗透调节、维持细胞膜稳定性、提供能量、氮同化产物和抗氧化能力；在复合处理下，细胞膜损伤减轻，与仅铅胁迫相比，保护酶活性增加，在重度铅复合处理下POD活性增加最多（49.14%）。在轻度铅胁迫下，高浓度CO导致细胞抗氧化能力增强、三羧酸循环中间产物含量增加以及脂肪酸去饱和；在重度铅胁迫下，高浓度CO使许多糖、多元醇和氨基酸含量作为渗透调节物质增加；次生代谢产物在铅胁迫和复合处理下发挥重要作用。本研究的目的是为未来水稻在高浓度CO下对铅胁迫的响应提供一种可能的分子机制。
