H2O2作为信号分子参与调控大豆根分泌柠檬酸抗铝毒分子机理仍不清楚。前期研究表明铝胁迫增加敏感型大豆根H2O2积累，降低大豆根质膜H+-ATP酶水解活性和柠檬酸分泌。本研究将使用H2O2及其抑制剂和清除剂改变铝胁迫大豆根中H2O2含量，分析铝胁迫增加大豆根中累积的H2O2是否能调控质膜H+-ATP酶磷酸化水平及其与14-3-3蛋白结合作用；用质膜H+-ATP酶激活剂和抑制剂考察大豆根中H2O2含量的变化与质膜H+-ATP酶水解活性和氢泵活性及其柠檬酸分泌的相关性; 并用H2O2预处理大豆、过表达抗氧化酶和在C末端去掉103个氨基酸的不受磷酸化调控质膜H+-ATP酶的转基因大豆研究H2O2调控作用机理。研究结果将揭示铝胁迫增加大豆根积累H2O2调控柠檬酸分泌的分子机理，丰富和加深我们对植物应答铝胁迫过程中H2O2作用机理的认识，为利用基因工程操作提高植物耐铝能力提供新的策略和基因资源。

The molecular mechanisms of H2O2 as signaling molecule involved in regulating the citric acid secretion of soybean root to resist Al toxicity remains unclear. The results of the preliminary study of this project suggested that Al stress increased H2O2 accumulation and reduced the plasma membrane (PM) ATPase hydrolysis activity as well as citrate secretion in Al-sensitive soybean . This study will apply H2O2 and its production inhibitors as well as its scavengers to alter H2O2 content in soybean roots under Al stress. Then further investigation will be conducted to determine whether the Al-increased H2O2 in soybean roots would play a role in regulation of the PM ATPase phosphorylation level and its interaction with 14-3-3 proteins. Using the activator and inhibitor of PM ATPase, the correlations among changes in H2O2 concentration, PM ATPase hydrolysis activity, H+ pump activity, and citrate secretion in soybean roots will also be analyzed. The function of this mechanism will be studied with H2O2 pretreated soybean roots and transgenic plant overexpressing antioxidant enzymes and a PM ATPase without phosphorylation regulation. The results of these experiments will reveal the molecular mechanism of the H2O2 regulation on PM ATPase hydrolysis activity and citrate secretion in soybean roots under Al stress. The results of this project will be valuable for further understanding the functional mechanism of H2O2 during plant response to Al stress and provide novel strategies and gene resources for genetic engineering to enhance plant Al resistance.