Department of Plant Physiology, Faculty of Agronomy, Horticulture and Bioengineering, Poznan University of Life Sciences, 60-637 Poznan, Poland.
Department of Plant Ecophysiology, Faculty of Biology, Adam Mickiewicz University in Poznan, 61-614 Poznan, Poland.
Int J Mol Sci. 2022 Apr 6;23(7):4051. doi: 10.3390/ijms23074051.
Nitric oxide (NO) is an essential redox-signaling molecule operating in many physiological and pathophysiological processes. However, evidence on putative NO engagement in plant immunity by affecting defense gene expressions, including histone modifications, is poorly recognized. Exploring the effect of biphasic NO generation regulated by S-nitrosoglutathione reductase (GNSOR) activity after avr inoculation, we showed that the phase of NO decline at 6 h post-inoculation (hpi) was correlated with the rise of defense gene expressions enriched in the TrxG-mediated H3K4me3 active mark in their promoter regions. Here, we report that arginine methyltransferase PRMT5 catalyzing histone H4R3 symmetric dimethylation (H4R3sme2) is necessary to ensure potato resistance to avr . Both the pathogen and S-nitrosoglutathione (GSNO) altered the methylation status of H4R3sme2 by transient reduction in the repressive mark in the promoter of defense genes, and (a resistance marker), thereby elevating their transcription. In turn, the PRMT5-selective inhibitor repressed expression and attenuated the hypersensitive response to the pathogen. In conclusion, we postulate that lowering the NO level (at 6 hpi) might be decisive for facilitating the pathogen-induced upregulation of stress genes via histone lysine methylation and PRMT5 controlling potato immunity to late blight.
一氧化氮（NO）是一种重要的氧化还原信号分子，参与许多生理和病理生理过程。然而，关于 NO 通过影响防御基因表达（包括组蛋白修饰）参与植物免疫的假设，其证据尚未得到充分认识。本研究通过探测 S-亚硝基谷胱甘肽还原酶（GNSOR）活性调控的双相 NO 生成在 avr 接种后对植物防御的影响，发现接种后 6 小时（hpi）NO 下降的阶段与防御基因表达的增加有关，这些防御基因在启动子区域富集了 TrxG 介导的 H3K4me3 活性标记。本研究还报告了精氨酸甲基转移酶 PRMT5 催化组蛋白 H4R3 对称二甲基化（H4R3sme2）对于马铃薯抵抗 avr 至关重要。病原体和 S-亚硝基谷胱甘肽（GSNO）通过短暂降低防御基因启动子中抑制性标记物的方式改变 H4R3sme2 的甲基化状态，和 （抗性标记物），从而提高其转录水平。反过来，PRMT5 选择性抑制剂抑制了 的表达并减弱了对病原体的过敏反应。综上所述，本研究提出，降低 NO 水平（在 6 hpi）可能对于通过组蛋白赖氨酸甲基化和 PRMT5 来促进病原体诱导的应激基因上调从而控制马铃薯晚疫病的免疫至关重要。
