A SUVH-DNAJ/SDJ protein complex activates the expression of promoter-methylated genes in Arabidopsis.

DNA methylation is an epigenetic mark that is involved in regulation of gene expression, gene imprinting, genome stability and many other important biological processes (Zhu 2009; He et al. 2011; Zhang et al. 2018). DNA methylation mark is usually associated with gene silencing when occurring in promoter regions. In plants, DNA methylation can be established and maintained through different DNA methylation pathways, such as RNA-directed DNA methylation (RdDM) pathway; it can also be actively eliminated by ROS1-family mediated DNA demethylation pathway (Zhu 2009; Zhang et al. 2018). To obtain a desirable methylation pattern, plant DNA methylation and demethylation pathways need to function coordinately (Tang et al. 2016). The expression of ROS1 is positively regulated by RdDM components (Li et al., 2012). A previous study raised an important concept of "methyl-state sensor (methylstat)" in plants (Lei et al. 2015).