title: A SNF2-like protein facilitates dynamic control of DNA methylation.
abstract: DRD1 is a SNF2-like protein previously identified in a screen for mutants defective in RNA-directed DNA methylation of a seed promoter in Arabidopsis. Although the initial study established a role for DRD1 in RNA-directed DNA methylation, it did not address whether DRD1 is needed for de novo or maintenance methylation, or whether it is required for methylation of other target sequences. We show here that DRD1 is essential for RNA-directed de novo methylation and acts on different target promoters. In addition, an unanticipated role for DRD1 in erasure of CG methylation was shown when investigating maintenance methylation after segregating away the silencing trigger. DRD1 is unique among known SNF2-like proteins in facilitating not only de novo methylation of target sequences in response to RNA signals, but also loss of methylation when the silencing inducer is withdrawn. The opposing roles of DRD1 could contribute to the dynamic regulation of DNA methylation.
authors.affiliation: Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, UZA2, Pharmazie Zentrum, Althanstrasse 14/2D-541, 1090 Vienna, Austria.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Kanno
authors.forename: Werner
authors.initials: W
authors.lastname: Aufsatz
authors.forename: Estelle
authors.initials: E
authors.lastname: Jaligot
authors.forename: Michael Florian
authors.initials: MF
authors.lastname: Mette
authors.forename: Marjori
authors.initials: M
authors.lastname: Matzke
authors.forename: Antonius J M
authors.initials: AJ
authors.lastname: Matzke
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D018899:CpG Islands; D019175:DNA Methylation; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000502:physiology*; D020868:Gene Silencing; D011401:Promoter Regions, Genetic / Q000235:genetics; D018749:RNA, Plant / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018749:RNA, Plant; D000594:Amino Acid Oxidoreductases; C021883:nopaline synthase; D012321:DNA-Directed RNA Polymerases; C504888:DRD1 protein, Arabidopsis