Methylation as a crucial step in plant microRNA biogenesis.
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.
Yu
Bin
B
Waksman Institute, Rutgers University, Piscataway, NJ 08854, USA.
Yang
Zhiyong
Z
Li
Junjie
J
Minakhina
Svetlana
S
Yang
Maocheng
M
Padgett
Richard W
RW
Steward
Ruth
R
Chen
Xuemei
X
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
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