Department of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 41566, Republic of Korea.
Biomolecules. 2024 Nov 7;14(11):1417. doi: 10.3390/biom14111417.
Nitrogen fixation in legume nodules is crucial for plant growth and development. Therefore, this study aims to investigate the effects of nitric oxide [S-nitrosoglutathione (GSNO)] and silicon [sodium metasilicate (Si)], both individually and in combination, on soybean growth, nodule formation, leghaemoglobin (Lb) synthesis, and potential post-translational modifications. At the V1 stage, soybean plants were treated for 2 weeks with 150 µM GSNO, and Si at concentrations of 1 mM, 2 mM, and 4 mM. The results showed that NO and Si enhance the nodulation process by increasing phenylalanine ammonia-lyase activity and Nod factors (), attracting rhizobia and accelerating nodule formation. This leads to a greater number and larger diameter of nodules. Individually, NO and Si support the synthesis of Lb and leghaemoglobin protein () expression, ferric leghaemoglobin reductases (), and S-nitrosoglutathione reductase (). However, when used in combination, NO and Si inhibit these processes, leading to elevated levels of S-nitrosothiols in the roots and nodules. This combined inhibition may potentially induce post-translational modifications in , pivotal for the reduction of Lb to Lb. These findings underscore the critical role of NO and Si in the nodulation process and provide insight into their combined effects on this essential plant function.
豆科植物根瘤中的氮固定对于植物的生长和发育至关重要。因此，本研究旨在探讨一氧化氮 [S-亚硝基谷胱甘肽 (GSNO)] 和硅（偏硅酸钠 (Si)）单独和联合作用对大豆生长、根瘤形成、豆血红蛋白 (Lb) 合成以及潜在的翻译后修饰的影响。在 V1 期，用 150µM GSNO 和浓度为 1mM、2mM 和 4mM 的 Si 处理大豆植株 2 周。结果表明，NO 和 Si 通过增加苯丙氨酸解氨酶活性和 Nod 因子 () 来促进结瘤过程，吸引根瘤菌并加速根瘤形成，从而导致更多和更大直径的根瘤。单独使用时，NO 和 Si 支持 Lb 和豆血红蛋白蛋白 () 的合成、铁豆血红蛋白还原酶 () 和 S-亚硝基谷胱甘肽还原酶 ()。然而，联合使用时，NO 和 Si 抑制这些过程，导致根和根瘤中 S-亚硝基硫醇水平升高。这种联合抑制可能会诱导在根和根瘤中，对 Lb 还原为 Lb 至关重要的翻译后修饰。这些发现强调了 NO 和 Si 在结瘤过程中的关键作用，并深入了解它们对这一重要植物功能的联合影响。
