外源CO及NO对干旱胁迫下水稻糊粉层细胞死亡的影响

采用荧光显微技术结合药理学方法,以水稻(Oryza sativa L.)种子及其糊粉层为实验材料,研究外源CO、NO对干旱胁迫下水稻种子萌发过程中糊粉层细胞DNA降解及死亡的影响。结果表明:(1)干旱胁迫促进糊粉层细胞的死亡,且近胚端糊粉层细胞的死亡进程早于远胚端的细胞。(2)外源CO及NO供体处理能缓解干旱胁迫下水稻糊粉层细胞DNA的降解,延迟细胞死亡进程;CO专一性抑制剂及NO清除剂能逆转CO及NO的效应,缩短细胞死亡进程。(3)外源CO及NO供体促进干旱胁迫下水稻种子的萌发,CO专一性抑制剂及NO清除剂能抑制干旱胁迫下水稻种子的萌发。(4)CO合成酶抑制剂并不能抑制外源NO对干旱胁迫伤害的缓解效应,即CO能通过NO介导调节干旱胁迫下水稻种子糊粉层细胞的死亡及种子萌发。

Effects of Carbon Monoxide and Nitric Oxide on the Death of Rice Aleurone Cells during Drought Stress

Using fluorescence microscopy combined with pharmacological methods,we studied the effects of exogenous CO and NO on the DNA degradation and survival rate of aleurone cells in germinating rice (Oryza sativa L.) seeds and its aleurone layers under drought stress.The results showed:(1)The treatment of drought stress promoted the aleurone cells death,and the death of aleurone cells near the embryo occurred earlier than those in the far embryo.(2)Exogenous CO and NO donors alleviated the degradation of DNA in rice aleurone cells under drought stress,and delaying the process of cell death.Meanwhile,effects of CO and NO were reversed by CO specific inhibitor and NO scavenger,and shortening the process of cell death.(3)Exogenous CO and NO donor promoted the germination of rice seeds under drought stress.However,CO specific inhibitor and NO scavengers inhibited the germination of rice seed under drought stress.(4)The experimental results also revealed that CO mediated by NO regulated the aleurone cells death and germination of rice seeds under drought stress.