A comprehensive analysis of precursor microRNA cleavage by human Dicer

作者：Feng Yong; Zhang Xiaoxiao; Graves Paul; Zeng Yan^*

来源：RNA-A Publication of the RNA Society, 2012, 18(11): 2083-2092.

DOI：10.1261/rna.033688.112

• Dicer
• pre-miRNA
• RNA binding
• RNA processing
• secondary structure

Dicer cleaves double-stranded RNAs (dsRNAs) or precursor microRNAs (pre-miRNAs) to yield similar to 22-nt RNA duplexes. The pre-miRNA structure requirement for human Dicer activity is incompletely understood. By large-scale in vitro dicing assays and mutagenesis studies, we showed that human Dicer cleaves most, although not all, of the 161 tested human pre-miRNAs efficiently. The stable association of RNAs with Dicer, as examined by gel shift assays, appears important but is not sufficient for cleavage. Human Dicer tolerates remarkable structural variation in its pre-miRNA substrates, although the dsRNA feature in the stem region and the 2-nt 3'; -overhang structure in a pre-miRNA contribute to its binding and cleavage by Dicer, and a large terminal loop further enhances pre-miRNA cleavage. Dicer binding protects the terminal loop from digestion by S1 nuclease, suggesting that Dicer interacts directly with the terminal loop region.

• 出版日期2012-11
• 单位武汉大学