The interaction between DCL1 and HYL1 is important for efficient and precise processing of pri-miRNA in plant microRNA biogenesis.
It has been reported that some double-stranded RNA (dsRNA) binding proteins interact with small RNA biogenesis-related RNase III enzymes. However, their biological significance is poorly understood. Here we examine the relationship between the Arabidopsis microRNA- (miRNA) producing enzyme DCL1 and the dsRNA binding protein HYL1. In the hyl1-2 mutant, the processing steps of miR163 biogenesis were partially impaired; increased accumulation of pri-miR163 and reduced accumulation of short pre-miR163 and mature miR163 as well as misplaced cleavages in the stem structure of pri-miR163 were detected. These misplaced cleavages were similar to those previously observed in the dcl1-9 mutant, in which the second double-stranded RNA binding domain of the protein was disrupted. An immunoprecipitation assay using Agrobacterium-mediated transient expression in Nicotiana benthamiana showed that HYL1 was able to form a complex with wild-type DCL1 protein, but not with the dcl1-9 mutant protein. We also examined miR164b and miR166a biogenesis in hyl1-2 and dcl1-9. Increased accumulation of pri-miRNAs and reduced accumulation of pre-miRNAs and mature miRNAs were detected. Misplaced cleavage on pri-miR164b was observed only in dcl1-9 but not in hyl1-2, whereas not on pri-miR166a in either mutant. These results indicate that HYL1 has a function in assisting efficient and precise cleavage of pri-miRNA through interaction with DCL1.
Kurihara
Yukio
Y
Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan.
Takashi
Yuasa
Y
Watanabe
Yuichiro
Y
D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D012323:RNA Processing, Post-Transcriptional; D012330:RNA, Double-Stranded / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012231:Rhizobium / Q000235:genetics; D043244:Ribonuclease III / Q000235:genetics / Q000378:metabolism*; D014026:Nicotiana / Q000235:genetics
D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; C420966:HYL1 protein, Arabidopsis; D035683:MicroRNAs; D012330:RNA, Double-Stranded; D016601:RNA-Binding Proteins; C402383:DCL1 protein, Arabidopsis; D043244:Ribonuclease III