title: Methylation as a crucial step in plant microRNA biogenesis.
abstract: Methylation on the base or the ribose is prevalent in eukaryotic ribosomal RNAs (rRNAs) and is thought to be crucial for ribosome biogenesis and function. Artificially introduced 2'-O-methyl groups in small interfering RNAs (siRNAs) can stabilize siRNAs in serum without affecting their activities in RNA interference in mammalian cells. Here, we show that plant microRNAs (miRNAs) have a naturally occurring methyl group on the ribose of the last nucleotide. Whereas methylation of rRNAs depends on guide RNAs, the methyltransferase protein HEN1 is sufficient to methylate miRNA/miRNA* duplexes. Our studies uncover a new and crucial step in plant miRNA biogenesis and have profound implications in the function of miRNAs.
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Yang
authors.forename: Junjie
authors.initials: J
authors.lastname: Li
authors.forename: Svetlana
authors.initials: S
authors.lastname: Minakhina
authors.forename: Maocheng
authors.initials: M
authors.lastname: Yang
authors.forename: Richard W
authors.initials: RW
authors.lastname: Padgett
authors.forename: Ruth
authors.initials: R
authors.lastname: Steward
authors.forename: Xuemei
authors.initials: X
authors.lastname: Chen
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D013058:Mass Spectrometry; D008745:Methylation; D035683:MicroRNAs / Q000737:chemistry / Q000378:metabolism*; D016376:Oligonucleotides, Antisense; D018749:RNA, Plant / Q000737:chemistry / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000737:chemistry / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012266:Ribose / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D029681:Arabidopsis Proteins; C450825:HEN1 protein, Arabidopsis; D035683:MicroRNAs; D016376:Oligonucleotides, Antisense; D018749:RNA, Plant; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D012266:Ribose