An RNA polymerase II-and AGO4-associated protein acts in RNA-directed DNA methylation
Type
ArticleAuthors
Gao, ZhihuanLiu, Hai-Liang
Daxinger, Lucia
Pontes, Olga
He, Xinjian
Qian, Weiqiang
Lin, Huixin
Xie, Mingtang
Lorkovic, Zdravko J.
Zhang, ShouDong
Miki, Daisuke
Zhan, Xianqiang
Pontier, Dominique
Lagrange, Thierry
Jin, Hailing
Matzke, Antonius J.
Matzke, Marjori
Pikaard, Craig S.
Zhu, Jian-Kang
KAUST Department
Plant Stress Genomics Research LabDate
2010-04-21Metadata
Show full item recordAbstract
DNA 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.Citation
Gao 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.Publisher
Springer NatureJournal
NatureISSN
00280836PubMed ID
20410883PubMed Central ID
PMC2865564Handle URI
http://hdl.handle.net/10754/325291Scopus Count
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