An RNA polymerase II-and AGO4-associated protein acts in RNA-directed DNA methylation
Lorkovic, Zdravko J.
Matzke, Antonius J.
Pikaard, Craig S.
KAUST DepartmentAcademic Affairs
Biological and Environmental Science and Engineering (BESE) Division
Center for Desert Agriculture
Office of the VP
Plant Stress Genomics Research Lab
Online Publication Date2010-04-21
Print Publication Date2010-05
Permanent link to this recordhttp://hdl.handle.net/10754/325291
MetadataShow full item record
AbstractDNA methylation is an important epigenetic mark in many eukaryotes. In plants, 24-nucleotide small interfering RNAs (siRNAs) bound to the effector protein, Argonaute 4 (AGO4), can direct de novo DNA methylation by the methyltransferase DRM2 (refs 2, 4-6). Here we report a new regulator of RNA-directed DNA methylation (RdDM) in Arabidopsis: RDM1. Loss-of-function mutations in the RDM1 gene impair the accumulation of 24-nucleotide siRNAs, reduce DNA methylation, and release transcriptional gene silencing at RdDM target loci. RDM1 encodes a small protein that seems to bind single-stranded methyl DNA, and associates and co-localizes with RNA polymerase II (Pol II, also known as NRPB), AGO4 and DRM2 in the nucleus. Our results indicate that RDM1 is a component of the RdDM effector complex and may have a role in linking siRNA production with pre-existing or de novo cytosine methylation. Our results also indicate that, although RDM1 and Pol V (also known as NRPE) may function together at some RdDM target sites in the peri-nucleolar siRNA processing centre, Pol II rather than Pol V is associated with the RdDM effector complex at target sites in the nucleoplasm. © 2010 Macmillan Publishers Limited. All rights reserved.
CitationGao Z, Liu H-L, Daxinger L, Pontes O, He X, et al. (2010) An RNA polymerase II- and AGO4-associated protein acts in RNA-directed DNA methylation. Nature 465: 106-109. doi:10.1038/nature09025.
PubMed Central IDPMC2865564
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