拟南芥CBF_3和COR15a基因对转基因烟草抗寒性的影响

Effects of CBF_3 and COR15a on Cold Resistance of Transgenic Tobacco

为了分析CBF3和COR15a双价基因的抗寒价值,通过模式植物烟草抗寒性的改良,为其他经济作物的抗寒改良提供理论和实践依据。将低温诱导启动子AtRD29a分别控制的拟南芥CBF3低温应答转录激活因子基因和COR15a冷诱导基因一起转入烟草,通过低温处理实验、生理生化指标测定分析转基因烟草的抗寒性。结果表明:外源基因已经整合到烟草基因组中,转基因植株在1℃48 h未出现萎蔫,而非转基因植株1℃12 h即出现萎蔫状态;转基因植株LT50为-1.01℃左右,非转基因植株LT50为0.86℃,转基因植株的细胞膜伤害率比非转基因植株低20%,半致死温度低约1.87℃;转基因植株的POD活性、可溶性糖含量和Pro含量分别是非转基因植株的3.42、2.57、1.23倍。

Cold tolerance and photosynthesis of tobacco at low temperature were expected to be improved as a reference to the improvement of cold tolerance in other crops.And CBF3 cold response transcription activators of Arabidopsis thaliana was controlled by AtRD29a.The exogenous genes were successfully transformed into tobacco.Transgenic tobacco were inproved effectively.Cold tolerance test showed that transgenic plantlet with AtRD29a-CBF3 and AtRD29a-COR15a bivalent gene did not wilt during 48 h at 1 ℃,but non-transgenic plantlet wilt in 12h at 1 ℃.Electric conductivity was measured and described with logistic equation,and the results showed that LT50 of transgenic plantlet was-1.01 ℃,but non-transgenic plantlet was 0.86 ℃.Transgenic plantlet was lower 20 % and 1.87 ℃ than non-transgenic plantlet in cell membrane injury percentage and the semilethal low temperature,respectively.And POD activity,soluble sugar content,and proline content of the former are 3.42,2.57,and 1.23 times than that of the latter.