uORF翻译调控因子在植物抗病反应中的功能研究

翻译调控是控制植物免疫活性的重要途经，上游阅读框uORF是介导该调控的重要RNA元件，但目前对控制uORF功能的基因知之甚少。在病原微生物效应因子引起的免疫激活过程中，uORFs的翻译抑制作用被解除，使得转录因子TBF1积累帮助宿主建立免疫系统。我们已获得含有翻译报告基因uORFs-LUC植株，证明了其荧光水平的变化受到免疫信号调控，并在该遗传背景下通过化学诱变筛选得到了12株荧光增强的突变体。本研究将对其中dst7突变体进行系统研究。该突变体失去了响应免疫激活的翻译调控功能，无法帮助宿主建立免疫系统，我们将进一步利用分子生物学、遗传学、生物化学等手段分析该目标基因DST7参与翻译调控的信号通路。通过以上研究，我们将更加深入理解蛋白质翻译调控机制，并利用该调控机制改良作物的抗病害能力。

Global translational reprogramming is a fundamental layer of immune regulation in plants. It is mediated by the collaborative action between cis-RNA element and trans-acting factors. Upstream open reading frame (uORF) represents as one of the prevalent regulator mRNA cis-element, but the underlying trans-acting factors or the regulators are poorly understood. TBF1, a key transcription factor in plant growth-defense transition, is tightly controlled by uORFs at the translation level. However, this suppression control is alleviated upon the recognition of.pathogen effectors for the establishment of effector-triggered immunity (ETI). This information inspires us to identify uORF regulators which may control immunity through translational reprogramming. With the utilization of translation reporter uORFsTBF1-LUC, we have identified 12 mutants displaying increased LUC fluorescence, indicating the loss of uORF-mediated translational suppression. We will focus on dst7 mutant as it also compromises ETI responses. We propose to perform mass-spectrum to find out the interactors of DST7 and further to illustrate how those interactors participate in uORF-mediated translational control during ETI response. Our results will advance our understanding of translational control mechanisms during immune responses and provide another important layer of immune regulation for engineering disease resistant plants.