A role for RNAi in the selective correction of DNA methylation defects.
DNA methylation is essential for silencing transposable elements and some genes in higher eukaryotes, which suggests that this modification must be tightly controlled. However, accidental changes in DNA methylation can be transmitted through mitosis (as in cancer) or meiosis, leading to epiallelic variation. We demonstrated the existence of an efficient mechanism that protects against transgenerational loss of DNA methylation in Arabidopsis. Remethylation is specific to the subset of heavily methylated repeats that are targeted by the RNA interference (RNAi) machinery. This process does not spread into flanking regions, is usually progressive over several generations, and faithfully restores wild-type methylation over target sequences in an RNAi-dependent manner. Our findings suggest an important role for RNAi in protecting genomes against long-term epigenetic defects.
Teixeira
Felipe Karam
FK
Unité de Recherche en Génomique Végétale, CNRS UMR 8114, Institut National de la Recherche Argonomique UMR 1165, Université d'Evry Val d'Essonne, 91057 Evry Cedex, France.
Heredia
Fabiana
F
Sarazin
Alexis
A
Roudier
François
F
Boccara
Martine
M
Ciaudo
Constance
C
Cruaud
Corinne
C
Poulain
Julie
J
Berdasco
Maria
M
Fraga
Mario F
MF
Voinnet
Olivier
O
Wincker
Patrick
P
Esteller
Manel
M
Colot
Vincent
V
D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003433:Crosses, Genetic; D019175:DNA Methylation; D004251:DNA Transposable Elements; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D018745:Genome, Plant; D009154:Mutation; D034622:RNA Interference; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; C118957:DDM1 protein, Arabidopsis; D004251:DNA Transposable Elements; D018744:DNA, Plant; D004268:DNA-Binding Proteins; D018749:RNA, Plant; D034741:RNA, Small Interfering; D014157:Transcription Factors; D012324:RNA-Dependent RNA Polymerase