GSE118153 RdDM-independent de novo and heterochromatin DNA methylation by plant CMT and DNMT3 orthologs [Bisulfite-Seq]

Contributors : Rafael Yaari ; Aviva Katz ; Katherine Domb ; Keith D Harris ; Assaf Zemach ; Nir OhadSeries Type : Methylation profiling by high throughput sequencingOrganism : Physcomitrella patensDNA methylation, the addition of a methyl group to a cytosine base, is catalyzed by DNA methyltransferases (DNMTs). DNMTs evolved to mediate methylation at different contexts, genetic elements, and chromatin configurations. Plants encode for four types of DNMTs, namely methyltransferase 1 (MET1), DNA methyltransferase 3 (DNMT3), chromomethylase (CMT), and domain rearranged methyltransferase (DRM). So far, most studies focused on angiosperm DNMTs. Here, we profiled whole genome and de novo methylation activities in the moss plant, Physcomitrella patens, mutated in either of its DNMTs, including in DNMT3, a DNMT that so far never been investigated in plants. We found PpDNMT3b to function as a de novo methylase of CG and CHH sites (H= A, C, or T) and for methylating almost the entire P. patens CHH methylome. We found PpCMT to methylate CHG sites de novo, to maintain all of CHG methylome, and to regulate CHH methylome in a H3K9me2 dependent manner. DRMs and RdDM weakly targets euchromtatic TEs and are not necessarily required for de novo methylation. P. patens diverged from angiosperms about 400 million years ago, which allowed us to decipher the way DNA methylation and DNMTs evolved during plant evolution. De novo methylation in early plants was most likely performed by DNMT3 and ...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Methylation profiling by high throughput sequencing Physcomitrella patens Source Type: research