Fig. 1: Endurance exercise training leads to a reduced mRNA m⁶A methylation level.

a The global mRNA m⁶A level in swimming exercise-trained murine hearts (n = 6 /group). b Metagene profile demonstrating the distribution of m⁶A peaks across mRNA transcripts in the mouse hearts of the swim and control group. UTR, untranslated Region. CDS, coding sequence. c Sequence motif identified consensus motif within m⁶A peaks by MeRIP-seq in control and swim group, respectively. Binomial distribution test (two-sided). d Volcano plot of the m⁶A enrichment in mRNAs of swim and control murine hearts. m⁶A mRNAs with significantly hypermethylated peak (red) and hypomethylated peak (green) enrichment is highlighted (p-value < 0.05, fold change > 1.5). Negative binomial test (two-sided). e Correlation between the level of gene expression and changes in m⁶A modification levels in the swim and control hearts. f Integrative genomics viewer (IGV) tracks revealing the results of meRIP-seq (Red) and RNA-seq (Blue) reads distributions in Mettl14 mRNA of the swim (n = 3 independent biological samples) and control mouse hearts (n = 4 independent biological samples). Plots are the medians of the n replicates presented. g Western blot analyses of METTL14 in whole lysates isolated from the hearts of swim and control murine (n = 6 mice/group). h qPCR analysis of Mettl14 mRNA expression levels in the hearts with or without swim training (n = 6 mice/group). i The methylation levels of Mettl14 mRNA in the swim and control hearts was measured by MazF-qPCR (n = 6 mice/group). The levels of a targeted amplicon (labeled “T”) is measured against a control (labeled “C”) amplicon in a MazF-digested sample and normalized against a non-digested sample. Seq, sequencing. IP, immunoprecipitation. All data are expressed as means ± SD. a, g, h, i Independent-sample t-test, two-sided. Source data are provided as a Source Data file.