PDF(Pubmed)
Abstract：
Plants respond more efficiently when confronted with previous similar stress. In the case of pathogens, this memory of a previous infection confers resistance to future ones, which possesses a high potential for agricultural purposes. Some of the defense elements involved in this resistance phenotype, as well as epigenetic mechanisms participating in the maintenance of the memory, are currently known. However, the intracellular cascade from pathogen perception until the establishment of the epigenetic memory is still unexplored. Here, through the induction of mitochondrial stress by exogenous applications of Antimycin A in Arabidopsis thaliana plants, we discovered and characterized a role of mitochondrial stress in plant-induced resistance. Mitochondrial stress-induced resistance (MS-IR) is effective locally, systemically, within generation and transgenerationally. Mechanistically, MS-IR seems to be mediated by priming of defense gene transcription caused by epigenetic changes. On one hand, we observed an increment in the deposition of H3K4me3 (a positive epigenetic mark) at the promoter region of the primed genes, and, on the other hand, the DNA (de)methylation machinery seems to be required for the transmission of MS-IR to the following generations. Finally, we observed that MS-IR is broad spectrum, restricting the colonization by pathogens from different kingdoms and lifestyles. Altogether, this evidence positions mitochondria as a prominent organelle in environment sensing, acting as an integrating platform to process external and internal signals, triggering the appropriate response, and inducing the epigenetic memory of the stress to better react against future stressful conditions.
摘要：
当面对先前类似的胁迫时，植物的反应更有效。在病原体的情况下，这种对先前感染的记忆赋予了对未来感染的抵抗力，具有很高的农业潜力。这种抗性表型涉及的一些防御要素，以及参与维持记忆的表观遗传机制，目前已知。然而,从病原体感知到建立表观遗传记忆的细胞内级联仍未被探索。这里,通过在拟南芥植物中外源施用抗霉素A诱导线粒体胁迫，我们发现并表征了线粒体胁迫在植物诱导抗性中的作用。线粒体应激诱导的抗性（MS-IR）是局部有效的，系统性地,代代相传。机械上,MS-IR似乎是由表观遗传变化引起的防御基因转录的启动介导的。一方面,我们观察到H3K4me3（阳性表观遗传标记）在引物基因启动子区域的沉积增加，and,另一方面,DNA（去）甲基化机制似乎是MS-IR传递给后代所必需的。最后,我们观察到MS-IR是广谱的，限制来自不同王国和生活方式的病原体定植。总之,这一证据将线粒体定位为环境感知中的重要细胞器，充当处理外部和内部信号的集成平台，触发适当的响应，并诱导压力的表观遗传记忆，以更好地应对未来的压力条件。
