The Effects of Low Temperature on the Global Increase of N6-methyldeoxyadenosine in Arabidopsis thaliana and Rice
N6-methyldeoxyadenosine (6mA) is a newly-discovered DNA modification that plays a role in regulating plant adaptation to abiotic stresses. However, the changes and molecular regulatory mechanisms of N6-methyldeoxyadenosine under cold stress in plants remain uncertain. Here, we found the global level of 6mA in both Arabidopsis and rice are raised after cold treatment. Genome-wide profiling of 6mA revealed that 6mA peaks are primarily distributed within gene body regions under both normal and low-temperature conditions. Additionally, genes that were up-methylated were enriched in various biological processes, while down-methylated genes did not exhibit any significant enrichment. Association analysis showed that 6mA was positively correlated with gene expression level and 6mA-containing genes displayed a significantly higher expression level than non-6mA-containing genes. Joint analysis of the 6mA methylome and transcriptome of Arabidopsis and rice revealed that the fluctuations in 6mA levels caused by exposure to cold did not correlate with the changes of transcript levels in response to low temperatures. Moreover, we found that 6mA modified orthologous genes exhibit high expression levels. However, upon cold treatment, only a small amount of differentially 6mA-methylated orthologous genes were shared between Arabidopsis and rice. In sum, this study profiled the changes of 6mA in response to cold temperature and has unlocked the potential of this DNA modification in regulating the expression of stress-related genes. Overall design: Comparative gene expression profiling analysis of 6mA-IP-seq ang RNA-seq data for Low Temperature in Arabidopsis thaliana and Rice.