BrGRF5基因参与植物生长以及盐和渗透胁迫抗性的调控

BrGRF5 Gene is Involved in the Regulation of Plant Growth and Resistance to Salt and Osmotic Stress

大白菜(Brassica rapa L.ssp.pekinensis)年播种面积约2×10^(6)hm^(2),在保障国民蔬菜正常供应中发挥了重要作用。叶是大白菜的主要食用器官,因此挖掘调控大白菜叶大小发育的关键基因将会对下一步通过基因工程等手段改良大白菜提供帮助。本研究从大白菜自交系‘福山包头’中克隆了一个GRF基因,命名为BrGRF5。通过生物信息学的分析发现,BrGRF5基因含有1个内含子,CDS序列长1044 bp,在进化上BrGRF5与拟南芥AtGRF7处于同一个分支并且二者的氨基酸一致性高达70.7%,暗示二者在功能上可能具有一定的相似性。进一步的研究也证实了上述猜测,在拟南芥中过量表达BrGRF5基因明显促进了转基因植株不同组织器官的增大,但也同时降低了转基因植株对盐和渗透胁迫的抗性,该结果与对AtGRF7的研究结果一致。研究结果将为下一步BrGRF5基因应用于大白菜遗传改良提供一定的基础。

Chinese cabbage(Brassica rapa L.ssp.pekinensis)is one of China's most important vegetable crops,with an annual sown area of about 2×10^(6)hm^(2).Chinese cabbage is a leafy vegetable,and its leaves are the main edible organ.Therefore,it's very important to explore the key gene that's involved in leaf size and developments,and yield of Chinese cabbage using plant biotechnology and genetic engineering technology.In this study,a GRF gene named BrGRF5 was cloned from Chinese cabbage inbred line cultivar'Fushanbaotou'.BrGRF5 gene contains an intron with a length of CDS 1044 bp.Phylogenetic analysis suggested that BrGRF5 and Arabidopsis AtGRF7 have 70.7%amino acid identity and may have close evolutionary and biological functions.Overexpression of BrGRF5 lines significantly enhanced the growth of different tissues and organs of transgenic Arabidopsis,but also reduced the resistance to salt and osmotic stress.The results of this study will provide a basis for the further application of BrGRF5 gene in genetic improvement of Chinese cabbage.