为了考察AMP(Adenosine 5’-monophosphate)对铝耐受型丹波黑大豆(RB)柠檬酸的分泌及铝抗性的影响,在50 mmol·L^-1铝溶液中添加100 mmol·L^-1AMP共处理RB,结果表明RB根的相对生长率显著小于单独用50 mmol·L^-1铝胁迫处理的植株。免疫共沉淀分析显示铝胁迫下AMP的存在降低RB根中14-3-3蛋白与磷酸化质膜H+-ATP酶的相互作用,使根尖质膜H+-ATP酶活性降低约1倍,氢泵活性和H+分泌能力显著降低,根柠檬酸的分泌量减少约1倍。说明铝胁迫下AMP通过抑制14-3-3蛋白和质膜H+-ATP酶的互作来减少RB根尖的氢泵活性和柠檬酸分泌作用,从而降低RB根的相对生长率及其对铝胁迫的耐受性。
To investigate the effect of Adenosine 5'-monophosphate( AMP) on the citrate secretion and Al-resistance of Alresistant Tamba black soybean( RB). RB was cotreated with AMP and 50 mmol·L^-1Al. The results showed that the relate root growth rate of RB co-treated with 100 mmol·L^-1AMP and 50 mmol·L^-1Al for 8 h was significantly lower than that of the plants treated with 50 mmol · L^-1Al alone. Co-immunoprecipitation showed that the presence of AMP under Al stress decreased the Al-enhanced interaction of PM H+-ATPase and 14-3-3 protein in root tips of RB,which reduced PM H+-ATPase activity by approximately 1-fold and thereby led to a significant decrease in H+efflux and citrate secretion( approximately 1-fold) in RB roots. Those results indicated that AMP decreases H+activity and citrate exudation in RB via its inhibition on the interaction between 14-3-3 protein and PM H+-ATPase under Al stress,thereby reducing the relate root growth rate of RB and its Al-tolerance.