程序降温处理过程中Nutlin-3对含水生菜种子抗冷性的影响

Effects of Nutlin-3 on chilling resistance of hydrated lettuce seeds(Lactuca sativa)

以含水生菜种子为试验材料,通过添加外源动物泛素E3连接酶抑制剂(Nutlin-3),研究其对程序降温过程中含水生菜种子抗冷性的影响。结果表明:程序降温速率为60℃∕h的条件下,添加Nutlin-3会促进种子的耐冻性,发芽率高于对照组,特别是在-20℃条件下最为明显。说明程序降温过程中,泛素化调节参与了种子的抗冷过程。对泛素相关基因进行实时荧光定量PCR检测发现,在降温至-20℃时,Nutlin-3抑制了泛素相关基因HOS1的表达水平,而促进了冷相关转录因子ICE1的表达水平,E3泛素连接酶基因COP1也受到Nutline-3的促进。同时,Nutlin-3对SOD活性有影响,但是对脯氨酸含量无明显作用。

In order to study the effects of Nutlin-3 on chilling resistance of hydrated Lactuca sativa seeds during programmed cooling,the seeds were imbibed with exogenous animal ubiquitin E3 ligase inhibitors(Nutlin-3)before treated with programmed cooling.The results showed that Nutlin-3 enhanced the freezing tolerance of lettuce seeds after cooling(with the rate of 60℃∕h).i.e,the germination rate of seeds imbibed with Nutlin-3 was higher than that of the control imbibition group,which was the most obvious when the temperature was reduced to be-20℃.This result indicated that in the process of programmed cooling,the regulation of ubiquitination was involved in the freezing resistance of seeds.Real-time quantitative PCR analysis of ubiquitin-related genes indicated that Nutlin-3 inhibited the expression of HOS1 and promoted the expression of anti-freezing factor ICE1 after cooling the seeds to be-20℃,E3 ubiquitin ligase gene COP1 was also promoted by Nutlin-3.At the same time,Nutlin-3 effected SOD activity,but had not effects on proline content in seeds.