转晚期胚胎发生丰富蛋白(LEA)基因棉花及抗旱性分析

本研究将紫杆柽柳(Tamarix and rossowii Litv)晚期胚胎发生丰富蛋白(LEADQ663481)基因导入新疆早熟棉新陆早18号,通过冬季海南加代、夏季新疆继代的方法获得T3代转基因棉花株系。从40株大田卡那霉素检测阳性植株中,经过PCR筛选证明3株为阳性的转化株。在室内条件下,对转化株幼苗进行水培实验,并用12%(w/v)PEG-6000处理12h模拟干旱胁迫。结果显示,干旱胁迫之后,转LEA基因棉花基因表达量显著增加;丙二醛生成量显著降低;游离脯氨酸、可溶性糖、可溶性蛋白的生成量显著增加;棉花表型分析也证明了转LEA基因棉花抗旱性有提高。培养45d后,转LEA基因棉花的生物量高于非转基因棉花。本研究结果表明,在干旱胁迫条件下,转LEA基因棉花表现出了优良的生长和生理优势,显示出转LEA基因棉花能提高棉花的抗旱能力。

Transgenic Cotton with Late Embryogenesis Abundant Protein(LEA) Gene and its Drought Tolerance

The open reading frames of Late Embryogenesis Abundant Protein(LEA DQ663481) Gene,from Tamarix and rossowii Litv,were introduced into the Xinjiang early-maturing cotton,Xinluzao18.T3 transgenic cotton plants were obtained through generation-adding in Hainan during winter and subculture in Xinjiang during summer from 40 plants with kanamycin positive resistance in the field,three individual positive transgenic cotton plants were obtained through PCR identification.These growing cotton shoots were cultured in room by hydroponic system and had been treated by 12%(w/v) PEG-6000 for 12 hours to simulate drought stress.Real-time quantitative RT-PCR analysis indicates the expression of LEA gene is higher in transgenic plants than in non-transgenic ones after that treatment.The contents of proline,soluble proteins and soluble sugar are also significantly higher in transgenic plants under drought stress.On the contrary,the malonyldiadehyde(MDA) content is significantly lower.The phenotypes of transgenic plants also indicate that LEA gene enhance their drought resistance.In addition,the height and fresh weight of transgenic plants after having been cultivated for 45 days are much higher than those of non-transgenic plants.These results demonstrate that the LEA gene is expressed well in the cotton plants,and could be used in genetic engineering for cotton to increase drought resistance.