摘要
植物中RNA介导的胞嘧啶甲基化(RdDM)在调节基因表达、调控转座子的活动和防御病毒等方面发挥重要作用。水杨酸(salicylic acid, SA)是一个重要的信号分子,能够诱导抗性基因的表达。SA途径能被RNA病毒激活,但其分子机制并不清楚。本研究中,我们证明了由RNA病毒编码的HC-Pro蛋白(Hepercomponent protease)在SA途径ACD6启动子区的DNA去甲基化过程中起作用。植物中HC-Pro的过表达增加了SA途径防御基因ACD6和PR5的表达。研究结果揭示了在HC-Pro转基因拟南芥中HC-Pro干扰DNA甲基化并激活SA途径,并阐明了RNA病毒激活SA途径的分子机制,为研究植物病毒与宿主互作的分子机制提供了研究依据。
RNA mediated cytosine methylated(RdDM) in plants plays an important role in regulating gene expression, the activity of transposons and defending against viruses. Salicylic acid(SA) is an important signalling molecule, which can induce the expression of resistance genes. SA pathway can be activated by RNA viruses, but the molecular mechanism was not clear. In this study, we demonstrated that heper-component protease(HC-Pro) encoded by RNA virus played a role in DNA demethylation at the promoter of ACD6 in the SA pathway. The overexpression of HC-Pro in plants increases the expression of defence genes ACD6 and PR5 in the SA pathway. The results revealed that HC-Pro interfered in DNA methylation and activated the SA pathway in HC-Pro transgenic Arabidopsis thaliana, and clarified the molecular mechanism that the SA pathway was activated by RNA viruses, and provided research basis for studying the molecular mechanism of the interaction between plant viruses and hosts.
引文
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