Genetic effects on non-CG DNA methylation [Methyl-C-seq]

The epigenome, in particular variation of DNA methylation profiles across individuals, has long been of interest as a modifier of the genetic code, with “mutations” reflecting past environments, stochastic events, or genetic regulation. To address this issue, we dissected an inherited epigenetics mark, mCHG methylation, using conditional GWAS approaches in Arabidopsis thaliana. Our study revealed the genome-wide mCHG levels largely share the variation with de novo methylation and are under the control of major trans-modifiers, including the key regulators CMT2, CMT3, MIR823A, and a novel regulator JMJ26 that specifically regulated RdDM-targeted TEs. Overall design: Methyl-C sequencing of mutants in Arabidopsis thaliana