桑树成花素基因FT表达载体的构建及转化拟南芥植株的早花现象

Expression Vector Construction of Mulberry Flowering Locus T Gene and Early Flowering in Transgenic Arabidopsis thaliana

成花素(flowering locus T,FT)是决定植物开花时间的关键信号因子。为研究桑树成花调控机制和FT基因的功能,构建插入桑树FT基因和报告基因GFP的植物双元表达载体p BE2133-FT-GFP,并通过蘸花方法转化拟南芥植株。利用卡那霉素抗性筛选和RT-PCR鉴定获得的转基因拟南芥植株,提取植株总蛋白进行Western blot分析,出现一条符合预期大小的阳性条带,证实桑树FT基因已整合进拟南芥基因组,并成功表达FT蛋白。转基因拟南芥播种25 d,虽然只长出5片幼叶,但却开始抽薹开花,表现出明显的早花性,证明桑树FT基因具有促进早期开花的功能。

In plant,flowering locus T（ FT） is the key signaling factor for determination of flowering time. In order to study the regulation mechanism of mulberry flowering and the function of FT gene,a plant binary expression vector named p BE2133-FT-GFP harboring both mulberry FT gene and GFP reporter gene was constructed and transformed into Arabidopsis thaliana by flower dipping method. Transgenic Arabidopsis thaliana plantlets were obtained through screening by kanamycin resistance and RT-PCR. Western blot analysis of total proteins from transgenic Arabidopsis thalina revealed a positive band of predicted molecular weight,demonstrating that mulberry FT gene had been integrated into genome of Arabidopsis thaliana and successfully expressed. At 25 d after the transgenic Arabidopsis thaliana seeds were sown,the plants began to flower. At this time,the plants had only sprouted out 5 young leaves,displaying obvious early flowering.These data verify that mulberry FT gene can lead to early blossoming.