miR395a-MdWRKY26调控苹果植物耐盐的分子机制

The molecular mechanism of miR 395 a-MdWRKY 26 regulating salt tolerance in apple plants

【目的】为了揭示miR 395 a-MdWRKY 26表达模式在盐处理下调控苹果耐盐性的分子机制,并且为苹果耐盐新品种的选育提供基础。【方法】以‘嘎啦’野生型苹果苗和通过稳定遗传转化方法得到的miR 395 a-OE、miR 395 a-RNAi、MdWRKY 26-OE、MdWRKY 26-RNAi转基因苹果苗为试验材料,对其进行200 mM的NaCl处理,观察表型并且用RT-qPCR检测盐处理下的表达量,用紫外分光光度计法测量丙二醛含量。【结果】结果表明,200 mM的NaCl处理后,与对照相比,miR 395 a-OE和MdWRKY 26-RNAi转基因植株受到的伤害程度较高,对盐更敏感;而MdWRKY 26-OE和miR 395 a-RNAi转基因植株受到的损害程度较轻,表明植株MdWRKY 26-OE和miR 395 a-RNAi转基因植株具有耐盐性。【结论】通过耐盐性分析,得到miR 395 a基因负调控苹果耐盐性,而MdWRKY 26基因发挥正调控作用。揭示了miR 395 a-MdWRKY 26调控苹果耐盐性的分子机理,可以减弱植物在盐处理下受到的伤害。

[Objective]In order to reveal the molecular mechanism of miR 395a-MdWRKY26 expression pattern downregulating salt tolerance in apples under salt treatment,and to provide a basis for the breeding of new salt tolerant apple varieties.[Methods]Wild type apple seedlings of'Gala'and transgenic apple seedlings of miR 395a-OE,miR 395a-RNAi,MdWRKY26-OE,and MdWRKY26-RNAi obtained through stable genetic transformation were used as experimental materials.They were treated with 200 mM NaCl to observe the phenotype and detect the expression level under salt treatment using RT qPCR.The content of malondialdehyde was measured using UV spectrophotometer.[Results]The results showed that after 200 mM NaCl treatment,compared with the control,miR 395a-OE and MdWRKY26-RNAi transgenic plants were more susceptible to damage and were more sensitive to salt;The damage to the MdWRKY26-OE and miR 395a RNAi transgenic plants was relatively mild,indicating that the MdWRKY26-OE and miR 395a RNAi transgenic plants have salt tolerance.[Conclusion]Through salt tolerance analysis,it was found that the miR395a gene negatively regulates salt tolerance in apples,while the MdWRKY26 gene plays a positive regulatory role.The molecular mechanism of miR 395a-MdWRKY26 regulating salt tolerance in apples has been revealed,which can weaken the damage to plants under salt treatment.