细胞外ATP对Cd胁迫下绿豆种子萌发保护机制的研究

Protective Role of Exogenous ATP against Cadmium Toxicity in Roots of Germinating Mung Bean Seeds

为了评价外源ATP对Cd胁迫下绿豆根生长的保护作用,对绿豆细胞死亡程度、根中超氧阴离子(O2.-)及根中O2.-进行了测定。结果表明,ATP(400μM)缓解了Cd(10μM)对根生长的抑制作用,降低了Cd诱导的根尖的细胞死亡。Cd诱导的根的生长抑制部分原因是由于Cd抑制细胞间质O2.-的水平。ATP处理对于Cd胁迫下细胞间质O2.-的水平有提升效果。因此,外源ATP可能通过维持Cd胁迫下细胞内的氧化还原状态而表现出其保护作用。

To evaluate the protective effect of exogenous ATP on the roots of mung bean exposed to Cadmium （Cd）, the cell death degree of mung bean and 02 ＊- of roots of mung bean were determined. The results showed that ATP （400μM） added to the hydroponics solution concurrently with Cd（ 10μM） alleviated roots growth inhibition and rescued mung bean roots from Cd-induced cell death. The supplement with ATP favored the elongation under Cd treatment and reduced Cd-induced cell death in roots. The Cd-mediated roots growth inhibition might at least in part be caused by the Cd inhibition of the apoplastic O2＊ - levels. ATP treatment exhibited a beneficial effects on the main- tenance of nomad amount of O2＊ - under cadmium stress. It indicated that the exogenous ATP-mediated rosponsos actually played a role in reestablishing the original redox state under Cd stress.