《植物生理学报》 2017, 53(4): 713-720

LEAFY启动子中W-box对LEAFY表达及拟南芥开花的影响

乔龙飞, 于延冲^*

青岛农业大学生命科学学院, 山东省植物生物技术重点实验室, 山东青岛 266109

通信作者：于延冲；E-mail: fuhuodeyihui@163.com

摘　要：

LEAFY (LFY)基因是影响植物开花发育的关键基因。本文克隆了正常的和W-box突变的2种LFY启动子, 构建2种启动子驱动LFY基因组DNA表达的载体, 导入拟南芥突变体lfy-2, 获得pLFY::gLFY lfy-2和mpLFY::gLFY lfy-2转基因纯系。开花时间分析发现, 前者与Col-0基本一致, 而后者开花较前者和Col-0晚; 花发育分析发现, pLFY::gLFY lfy-2花发育正常, mpLFY::gLFY lfy-2成花率88.3%, 仍有约12%的花发育异常, 类似于lfy-2的异常花。另外, 构建获得LFY::GUS和mLFY::GUS转基因纯系, GUS染色结果表明, 在拟南芥发育早期(萌发后8 d), 突变W-box影响了LFY的表达部位; 萌发后10和12 d时, 这种突变不再影响其表达部位, 而影响其表达量。以上结果表明, LFY启动子W-box的突变会造成LFY水平的下降, 进而影响其正常功能的行使。

关键词：拟南芥; LFY; 启动子; 开花; W-box

收稿：2016-10-17   修定：2017-02-28

资助：国家自然科学基金青年科学基金(31600224)和青岛农业大学高层次人才启动基金(1116018)。

Effect of W-box in LEAFY promoter on LEAFY expression and Arabidopsis flowering

QIAO Long-Fei, YU Yan-Chong^*

Shandong Key Laboratory of Plant Biotechnology, College of Life Sciences, Qingdao Agricultural University, Qingdao, Shandong 266109, China

Corresponding author: YU Yan-Chong; E-mail: fuhuodeyihui@163.com

Abstract:

LEAFY (LFY) is the key gene affecting plant flowering. In this study, native and W-box mutated LFY promoter were cloned and used to drive LFY genome DNA, then the constructions were transformed into lfy-2 mutant, finally, pLFY::gLFY lfy-2 and mpLFY::gLFY lfy-2 homozygous lines were obtained. Flowering time analysis indicated that the former flowered similarly to Col-0, while the latter flowered later than the former and Col-0. Flower development analysis showed that pLFY::gLFY lfy-2 developed normally, mpLFY::gLFY lfy-2 had 88.3% normal flower, about 12% flower developed abnormally, which liked the abnormal flower of lfy-2. In addition, LFY::GUS and mLFY::GUS homozygous lines were constructed. GUS staining showed that at 8 day after germination, mutated W-box affected the expression localization of LFY, at 10 and 12 day, this mutation no longer affected its expression localization but its transcription level. These results suggested that W-box mutatation of LFY promoter resulted in decreasing its transcription level, thereby affecting its function.

Key words: Arabidopsis thaliana; LFY; promoter; flowering; W-box