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Acknowledgments

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A) A Myc-epitope tagged DRM2 transgene was mutated to introduce amino acid substitutions in the UBA domains or the methyltransferase domain, depicted graphically. (B) Micrographs of intact nuclei stained with DAPI and immunostained using α-Myc antibodies. (C) Southern blots hybridized for the MEA-ISR repeat using DNA digested with the methyl-sensitive restriction enzyme MspI. (D) Graphical representation of bisulfite sequencing of MEA-ISR with % cytosine methylation shown for each genotype. Error bars represent 95% confidence limits (Wilson score interval). CG sequence contexts are shaded dark grey, CHG are shaded light grey and white represents CHH.Slotkin, R. K. & Martienssen, R. Transposable elements and the epigenetic regulation of the genome. Nat. Rev. Genet. 8, 272–285 (2007). DNA methylation at cytosines is an evolutionarily conserved epigenetic mechanism that is required for gene expression and genome stability ( 1– 3). Dysregulation of DNA methylation leads to developmental defects and various diseases in animals, most notably cancer and pleiotropic developmental defects in plants ( 4– 6), highlighting an essential role for DNA methylation in both kingdoms ( 3, 7). Nevertheless, the mechanisms of DNA methylation have diverged between plants and animals ( 3). In animals, de novo DNA methyltransferases DNMT3A and DNMT3B primarily mediate methylation of CpG dinucleotides ( 8, 9), with appreciable levels of CH (H = A, T, or C) methylation identified in oocytes, embryonic stem cells, and neural cells ( 10). Subsequently, CG methylation is maintained by DNA methyltransferase 1 (DNMT1) in a replication-dependent manner ( 11). In contrast, DNA methylation in plants is prevalent in all sequence contexts: CG, CHG, and CHH ( 3). Domains rearranged methyltransferase 2 (DRM2) mediates the establishment of DNA methylation in all three sequence contexts, whereas plant DNA methyltransferase 1 (MET1) and chromomethylase 3 (CMT3) maintain CG and CHG methylation, respectively ( 12– 14). chromomethylase 2 (CMT2) and DRM2 are jointly responsible for maintaining CHH methylation in long heterochromatic transposable elements (TEs) and short euchromatic TEs, respectively ( 15). However, the molecular mechanism underlying the divergent methylation patterns between plants and animals remains unclear.

Zhou, S. et al. Cooperation between the H3K27me3 chromatin mark and non-CG methylation in epigenetic regulation. Plant Physiol. 172, 1131–1141 (2016). Follow the instructions in Integrate the Appstore SDK to add the Appstore SDK into your Android project. setting up an AWS KMS key, see Using AWS KMS with Elastic Transcoder. Streaming DRM-Protected Content

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