DNA methylation dynamics during sexual reproduction in Arabidopsis thaliana.
Curr Biol
; 22(19): 1825-30, 2012 Oct 09.
Article
em En
| MEDLINE
| ID: mdl-22940470
ABSTRACT
DNA methylation maintains genome stability and regulates gene expression [1]. In mammals, DNA methylation is reprogrammed in the germline from one generation to the next [2]. In plants, it was considered that patterns of DNA methylation are stably maintained through sexual reproduction [3-6]. However, a recent report showed discrete variations of DNA methylation profiles from mother to daughter plants [7]. The mechanisms that explain these variations have remained unknown. Here, we report that maintenance DNA methyltransferases are barely expressed during Arabidopsis female gametogenesis. In contrast, after fertilization both maintenance and de novo DNA methyltransferases are expressed strongly in the embryo. Embryogenesis is marked by increased de novo DNA methylation, reaching levels that are further maintained in the adult plant. The accumulation of these epigenetic marks after fertilization silences a methylation-sensitive fluorescent reporter. De novo DNA methylation in the embryo provides a mechanism that could account for the gradual remethylation of experimentally demethylated genomes [8, 9]. In conclusion, we uncover that DNA methylation activity fluctuates during sexual reproduction. This cycle likely explains variations of genome-wide patterns of DNA methylation across generations in Arabidopsis [7, 10] and enables a limited degree of reprogramming of the epigenome.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
/
Metilação de DNA
/
Proteínas de Arabidopsis
/
Metiltransferases
Idioma:
En
Revista:
Curr Biol
Assunto da revista:
BIOLOGIA
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Singapura