生长素调控m6A修饰的机制研究

植物m6A修饰功能十分重要，已经被发现有调节生长发育等多方面功能。m6A修饰是动态变化的，而调控这一动态变化的机制还知之甚少。我们前期研究发现生长素能引发m6A修饰的上调，这一变化与两个蛋白相关：生长素感知复合体成员TMK4和m6A甲基转移酶复合体成员FIP37，它们能直接相互作用。同时，m6A修饰的缺失会影响生长素信号传递，暗示m6A修饰是生长素信号通路的重要一环。本研究拟用拟南芥为材料，运用多种生化手段验证TMK4与FIP37的相互作用，结合蛋白质谱研究TMK4对FIP37的磷酸化修饰，通过遗传证据揭示磷酸化对FIP37功能的影响。采用MeRIP-seq技术分析生长素对m6A修饰分布的影响，阐明m6A修饰对生长素信号传递的转录后调节。本项目旨在明确生长素对m6A修饰的影响，揭示TMK4感知生长素信号并通过磷酸化FIP37对其活性进行调节，进而在转录后水平精细调控生长素信号通路的机制。

It has been extensively reported that the function of N6-methyladenosine RNA modification (m6A) in plants is very important and diverse. m6A is highly dynamic, however, little is known about how the dynamics is achieved. We have found auxin could induce up-regulation of m6A. TMK4, a transmembrane kinase which is a component of auxin sensing complex, and FIP37, a core component of m6A methyltransferase complex, were found to be closely related to auxin triggered m6A up-regulation, they could interact with each other. We also found the transduction of auxin signal was dependent on m6A modification. Using Arabidopsis as a model system, we intend to apply multiple biochemical technics to verify the interaction between TMK4 and FIP37. To explore the phosphorylation of FIP37 catalyzed by TMK4, LC-MS and genetic analysis will be used. We plan to use MeRIP-seq to study auxin dependent transcriptome-wide m6A reprogramming. The mechanism of regulation of auxin signaling pathway by m6A will also be studied. Based on this project, we hope to find whether auxin can influence m6A modification, illuminate how TMK4 regulates activity of FIP37 by phosphorylation after sensing the auxin signal and explore the post-transcriptional regulation of auxin signaling pathway by m6A.