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Small RNAs guide histone methylation in Arabidopsis embryos.

ABSTRACT: Epigenetic reprogramming occurs during gametogenesis as well as during embryogenesis to reset the genome for early development. In flowering plants, many heterochromatic marks are maintained in sperm, but asymmetric DNA methylation is mostly lost. Asymmetric DNA methylation is dependent on small RNA but the re-establishment of silencing in embryo is not well understood. Here we demonstrate that small RNAs direct the histone H3 lysine 9 dimethylation during Arabidopsis thaliana embryonic development, together with asymmetric DNA methylation. This de novo silencing mechanism depends on the catalytic domain of SUVH9, a Su(Var)3-9 homolog thought to be catalytically inactive.

SUBMITTER: Parent JS

PROVIDER: S-EPMC8168562 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Small RNAs guide histone methylation in <i>Arabidopsis</i> embryos.

Parent Jean-Sébastien JS Cahn Jonathan J Herridge Rowan P RP Grimanelli Daniel D Martienssen Robert A RA

Genes & development 20210520 11-12

Epigenetic reprogramming occurs during gametogenesis as well as during embryogenesis to reset the genome for early development. In flowering plants, many heterochromatic marks are maintained in sperm, but asymmetric DNA methylation is mostly lost. Asymmetric DNA methylation is dependent on small RNA but the re-establishment of silencing in embryo is not well understood. Here we demonstrate that small RNAs direct the histone H3 lysine 9 dimethylation during <i>Arabidopsis thaliana</i> embryonic d ...[more]

PMID: 34016690

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