CK磷酸化转录延伸因子ELF调节拟南芥开花时间的分子机理

开花是高等植物营养生长至生殖生长过程转变过程，由内在生理状态和外界环境共同调控完成。拟南芥作为重要的模式植物，其一系列开花的基因已经相继被分离和克隆，然而转录延伸因子如何调控拟南芥开花还知之甚少。前人的研究显示，转录延伸因子是介导转录与组蛋白修饰的重要因子，我们的结果显示，转录延伸因子ELF与蛋白激酶CK直接相互作用，并且ELF的CTR结构域的苏氨酸能被CK特异地磷酸化，elf和ck突变体都具有开化早的表型，并共同调节下游基因FLC和MAF的表达水平和H3K4甲基化水平。在前期明确的分子特征与生理分析鉴定的基础之上，本申请拟从转录延伸因子突变体elf入手，着重解析延伸因子在拟南芥的开花途径的调控作用，阐述转录延伸因子调控植物开花的分子机理，研究转录延伸因子参与组蛋白修饰的方式。

Plant development progresses through distinct phases: vegetative growth, followed by is productive phase. Flower is transition from vegetative phases to reproductive phase in higher plant, which is controlled by the genetic background and environmental condition. Although a series of genes involved in flower pathway were characterized, little is known about transcriptional elongation factors. The previous results indicate transcriptional elongation factor mediate the transcriptional efficiency and histone modifications. Our preliminary results show that ELF，a transcriptional elongation factor, interact with CK kinase. Furthermore, CK can phosphorylated the threonine site of CTR domain of ELF. Most interestingly, loss-of-function of ELF and CK have early flowering phenotype owing to attenuated expression level and H3K4me3 at FLC and MAF loci in both mutants. Take together, our project is to understand the molecular mechanism of ELF in flowering time and histone modifications.