DELLA蛋白缺失对拟南芥干旱胁迫耐受性的影响

Drought Tolerance of DELLA Proteins Deficiency in Arabidopsis

为探索DELLA蛋白缺失对拟南芥耐旱能力的影响,对拟南芥野生型Ler和DELLA蛋白缺失突变体della进行干旱处理,测定存活率、萌发率、离体叶片的失水率、脯氨酸、可溶性糖和丙二醛含量,并对发挥植物细胞脱水保护功能的胚胎晚期丰富蛋白编码基因LEA和ABA应答基因LOX3、COR15b、COR413的表达量进行了检测。结果表明:(1)干旱21d后复水,della突变体的存活率明显高于野生型Ler;(2)della突变体在含甘露醇的固体培养基上的萌发率显著高于Ler;(3)della突变体离体叶片的失水速率明显低于Ler;(4)干旱胁迫后,della突变体脯氨酸、可溶性糖和丙二醛含量的积累低于Ler;(5)干旱胁迫后,della突变体的LEA基因上调表达程度高于Ler,而ABA应答基因上调表达程度低于Ler。研究表明,DELLA蛋白的缺失有助于提高植物抗旱能力。

To explore the effects of DELLA protein deficiency on drought tolerance in Arabidopsis,we treated DELLA proteins deficient mutant dellaby drought stress.The survival rate,germination rate,water loss rate,and contents of proline,soluble sugar,and malondialdehyde were measured.Meanwhile,the gene expression patterns of the late embryogenesis abundant protein coding genes LEAs,which play important roles in dehydration protection of plant cell,and ABA responsive genes,such as LOX3,COR15 b,and COR413,were investigated by qPCR.The results showed that：（1）after 21 days of drought stress and re-watering treatment,the survival rate of della mutant was significantly higher than that of wild type Ler;（2）the germination rate of della mutant was markedly higher than that of Ler on 1/2 MS with mannitol;（3）the water loss speed of leaves detached fromdella mutant was distinctly slower than that of Ler;（4）the contents of proline,soluble sugar,and malondialdehyde in della mutant were lower than that of Ler;（5）the up-regulated expression of LEAgenes in della mutant was higher than that of Ler,while the up-regulated expression of ABA responsive genes was lower.These results suggest that the deficiency of DELLA proteins improves the drought resistance in Arabidopsis.