Repression of CHROMOMETHYLASE 3 prevents epigenetic collateral damage in Arabidopsis

eLife

Ranjith K Papareddy¹  Katalin Páldi¹  Anna D Smolka¹  Claude Becker²  Patrick Hüther²  Michael D Nodine³ 

[1] Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, Vienna, Austria;Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, Vienna, Austria;Genetics, LMU Biocenter, Ludwig-Maximilians University, Martinsried, Germany;Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna Biocenter (VBC), Dr. Bohr-Gasse 3, Vienna, Austria;Laboratory of Molecular Biology, Wageningen University, Wageningen, Netherlands;

关键词: DNA methylation;    chromatin;    microRNA;    gene regulation;    epimutation;    A. thaliana;   

DOI  :  10.7554/eLife.69396

来源: eLife Sciences Publications, Ltd

【 摘 要 】

DNA methylation has evolved to silence mutagenic transposable elements (TEs) while typically avoiding the targeting of endogenous genes. Mechanisms that prevent DNA methyltransferases from ectopically methylating genes are expected to be of prime importance during periods of dynamic cell cycle activities including plant embryogenesis. However, virtually nothing is known regarding how DNA methyltransferase activities are precisely regulated during embryogenesis to prevent the induction of potentially deleterious and mitotically stable genic epimutations. Here, we report that microRNA-mediated repression of CHROMOMETHYLASE 3 (CMT3) and the chromatin features that CMT3 prefers help prevent ectopic methylation of thousands of genes during embryogenesis that can persist for weeks afterwards. Our results are also consistent with CMT3-induced ectopic methylation of promoters or bodies of genes undergoing transcriptional activation reducing their expression. Therefore, the repression of CMT3 prevents epigenetic collateral damage on endogenous genes. We also provide a model that may help reconcile conflicting viewpoints regarding the functions of gene-body methylation that occurs in nearly all flowering plants.

【 授权许可】

CC BY