Mao Fei, Xie Hairong, Shi Yucheng, Jiang Shasha, Wang Shuai, Wu Yufeng
National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Bioinformatics Center, Academy for Advanced Interdisciplinary Studies, Nanjing Agricultural University, Nanjing 210095, China.
Plants (Basel). 2023 Jun 19;12(12):2373. doi: 10.3390/plants12122373.
N6-methyldeoxyadenosine (6mA) is a recently discovered DNA modification involved in regulating plant adaptation to abiotic stresses. However, the mechanisms and changes of 6mA under cold stress in plants are not yet fully understood. Here, we conducted a genome-wide analysis of 6mA and observed that 6mA peaks were predominantly present within the gene body regions under both normal and cold conditions. In addition, the global level of 6mA increased both in and rice after the cold treatment. The genes that exhibited an up-methylation showed enrichment in various biological processes, whereas there was no significant enrichment observed among the down-methylated genes. The association analysis revealed a positive correlation between the 6mA level and the gene expression level. Joint analysis of the 6mA methylome and transcriptome of and rice unraveled that fluctuations in 6mA levels caused by cold exposure were not correlated to changes in transcript levels. Furthermore, we discovered that orthologous genes modified by 6mA showed high expression levels; however, only a minor amount of differentially 6mA-methylated orthologous genes were shared between and rice under low-temperature conditions. In conclusion, our study provides information on the role of 6mA in response to cold stress and reveals its potential for regulating the expression of stress-related genes.
N6-甲基脱氧腺苷（6mA）是最近发现的一种参与调节植物对非生物胁迫适应性的DNA修饰。然而，植物在冷胁迫下6mA的机制和变化尚未完全了解。在此，我们对6mA进行了全基因组分析，观察到在正常和寒冷条件下，6mA峰主要出现在基因体内区域。此外，冷处理后，拟南芥和水稻中6mA的整体水平均有所增加。表现出甲基化上调的基因在各种生物学过程中富集，而甲基化下调的基因之间未观察到显著富集。关联分析揭示了6mA水平与基因表达水平之间呈正相关。对拟南芥和水稻的6mA甲基化组和转录组进行联合分析发现，冷暴露引起的6mA水平波动与转录水平变化无关。此外，我们发现经6mA修饰的直系同源基因表现出高表达水平；然而，在低温条件下，拟南芥和水稻之间仅共享少量差异6mA甲基化的直系同源基因。总之，我们的研究提供了关于6mA在响应冷胁迫中的作用的信息，并揭示了其调节胁迫相关基因表达的潜力。
