乙醛脱氢酶基因(ALDH)转化番茄的研究

Studies on Transformation of Aldehyde dehydrogenase(ALDH) into Tomato

为了培育抗旱、耐盐番茄新品种,以拓宽番茄新的种质资源,为充分利用中国盐碱地资源奠定基础。以乙醛脱氢酶基因(ALDH)为目的基因,构建pBI-ALDH植物表达载体,经发根农杆菌(Agrobacterium rhizogens)介导采用共培养法转化番茄,通过分子生物学技术(PCR、Southern杂交、RT-PCR)和抗逆相关生理指标测定(相对电导率及丙二醛含量)相结合的方法对转基因番茄植株进行检测。研究结果表明:ALDH基因导入并整合到番茄的基因组中,在转录水平上可以稳定表达;在干旱、高盐和低温胁迫条件下,转基因植株较对照株的相对电导率和丙二醛含量均有所降低,证明转基因番茄植株的质膜受损程度有所降低;另外研究的转化率为10.78%。以上结果说明:转ALDH基因番茄对环境胁迫造成的伤害具有较强的抗性,即ALDH基因具有提高植物抗氧化胁迫的功能。

The study aimed to cultivate the new varieties tolerant to drought and salt in order to broaden the new tomato germplasm resources, establishing the foundation of making full use of saline-alkali soil resources in China. The aldehyde dehydrogenase gene （ALDH） was inserted into the pBI121 to obtain the pBI-ALDH plant expression vector, which was transformed into the tomato mediated by Agrobacterium rhizogenes using the co-culture method. The transgenic tomato plants were detected by molecular biology techniques （PCR, Southern blot , RT-PCR） and resistance-correlated physiological indices （relative electric conductivity and malondialdehyde content）. The results showed that ALDH gene had been integrated into the tomato genome and expressed stably at the transcriptional level; compared with the control plants, the relative electronic conductivity and MDA content of the transgenic plants both reduced under drought, high-salt and hypothermia stress conditions, which proved that the damage of the transgenic tomato plants plasma membrane was decreased; and the transformation rate was 10.78%. These results showed that the transgenic tomato plants with ALDH gene had stronger resistance to the damage caused by the environmental stress, which indicated that ALDHgene had increased the antioxidant capacity.