Degradation of microRNAs by a family of exoribonucleases in Arabidopsis.
microRNAs (miRNAs) play crucial roles in numerous developmental and metabolic processes in plants and animals. The steady-state levels of miRNAs need to be properly controlled to ensure normal development. Whereas the framework of miRNA biogenesis is established, factors involved in miRNA degradation remain unknown. Here, we show that a family of exoribonucleases encoded by the SMALL RNA DEGRADING NUCLEASE (SDN) genes degrades mature miRNAs in Arabidopsis. SDN1 acts specifically on single-stranded miRNAs in vitro and is sensitive to the 2'-O-methyl modification on the 3' terminal ribose of miRNAs. Simultaneous knockdown of three SDN genes in vivo results in elevated miRNA levels and pleiotropic developmental defects. Therefore, we have uncovered the enzymes that degrade miRNAs and demonstrated that miRNA turnover is crucial for plant development.
Ramachandran
Vanitharani
V
Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California Riverside, Riverside, CA 92521, USA.
Chen
Xuemei
X
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D060565:Argonaute Proteins; D005095:Exoribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017343:Genes, Plant; D026161:MADS Domain Proteins / Q000235:genetics; D008745:Methylation; D035683:MicroRNAs / Q000378:metabolism*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D018749:RNA, Plant / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D013379:Substrate Specificity
C117457:AGO1 protein, Arabidopsis; C091535:AP1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D060565:Argonaute Proteins; D026161:MADS Domain Proteins; D035683:MicroRNAs; D018749:RNA, Plant; D034741:RNA, Small Interfering; D005095:Exoribonucleases; C531524:SDN1 protein, Arabidopsis
RNA. 2004 Dec;10(12):1946-56
15525710
Curr Biol. 2005 Aug 23;15(16):1501-7
16111943
Science. 2005 Feb 11;307(5711):932-5
15705854
Nat Cell Biol. 2007 May;9(5):604-11
17435748
Nature. 2004 Feb 12;427(6975):645-9
14961122
EMBO J. 2000 Mar 15;19(6):1357-65
10716935
Nat Struct Mol Biol. 2008 May;15(5):523-30
18438418
Plant Cell. 2003 Nov;15(11):2730-41
14555699
EMBO J. 1998 Jan 2;17(1):170-80
9427751
Genes Dev. 2002 Jul 1;16(13):1616-26
12101121
Nature. 2003 Sep 18;425(6955):257-63
12931144
Nat Struct Mol Biol. 2008 May;15(5):531-3
18438419
J Biol Chem. 2000 Nov 24;275(47):36957-65
10948199
Plant Cell. 2006 May;18(5):1121-33
16531494
Science. 2004 Mar 26;303(5666):2022-5
12893888
Curr Biol. 2002 Sep 3;12(17):1484-95
12225663
Curr Biol. 2006 Jul 25;16(14):1459-64
16797182