Skip to main content
. Author manuscript; available in PMC: 2015 Jan 27.
Published in final edited form as: Natl Sci Rev. 2014 Jun;1(2):219–229. doi: 10.1093/nsr/nwu003

Figure 2. Maintenance of DNA methylation in different sequence contexts in Arabidopsis.

Figure 2

The maintenance of cytosine methylation in the CG sequence context requires DNA METHYLTRANSFERASE 1 (MET1). CHG methylation is mainly maintained by CHROMOMETHYLASE 3 (CMT3), which is guided by the histone H3K9me2 mark. DOMAINS REARRANGED METHYLTRANSFERASE 2 (DRM2) mediates the maintenance of CHH methylation at euchromatic short TEs or the edges of heterochromatic long TEs through the RNA-directed DNA methylation (RdDM) pathway. At the bodies of heterochromatic long TEs where the RdDM machineries cannot access, cytosine methylation in the CHH sequence context is maintained by CHROMOMETHYLASE 2 (CMT2). Crosstalks also exist between different DNA methylation pathways. Maintenance of CHH methylation at some loci requires CMT3 while maintenance of CHG methylation at some loci requires the RdDM pathway.