Efficient Silencing of Endogenous MicroRNAs Using Artificial MicroRNAs in Arabidopsis thaliana

• Published in: Molecular plant 2011, Vol.4 (1), p.157-170
• Main Authors: Eamens, Andrew L., Agius, Claire, Smith, Neil A., Waterhouse, Peter M., Wang, Ming-Bo
• Format: Article
• Language: English
• Subjects: Arabidopsis - genetics; Arabidopsis - metabolism; artificial microRNA; Base Sequence; Gene Expression Regulation, Plant; Gene Silencing; MicroRNA; MicroRNAs - chemical synthesis; MicroRNAs - chemistry; MicroRNAs - genetics; MicroRNAs - metabolism; miRNA; Molecular Sequence Data; Nucleic Acid Conformation; RNA silencing; RNA, Plant - chemistry; RNA, Plant - genetics; RNA, Plant - metabolism; RNA沉默; 人工; 微RNA; 拟南芥; 植物细胞; 高效利用
• ISSN: 1674-2052; 1752-9867
• DOI: 10.1093/mp/ssq061

We report here that the expression of endogenous microRNAs （miRNAs） can be efficiently silenced in Arabi- dopsis thaliana （Arabidopsis） using artificial miRNA （amiRNA） technology. We demonstrate that an amiRNA designed to target a mature miRNA directs silencing against all miRNA family members, whereas an amiRNA designed to target the stem-loop region of a miRNA precursor transcript directs silencing against only the individual family member targeted. Furthermore, our results indicate that amiRNAs targeting both the mature miRNA and stem-loop sequence direct RNA silencing through cleavage of the miRNA precursor transcript, which presumably occurs in the nucleus of a plant cell during the initial stages of miRNA biogenesis. This suggests that small RNA （sRNA）-guided RNA cleavage in plants occurs not only in the cytoplasm, but also in the nucleus. Many plant miRNA gene families have been identified via sequencing and bio- informatic analysis, but, to date, only a small tranche of these have been functionally characterized due to a lack of ef- fective forward or reverse genetic tools. Our findings therefore provide a new and powerful reverse-genetic tool for the analysis of miRNA function in plants.