Depletion of Human Micro-RNA miR-125b Reveals That It Is Critical for the Proliferation of Differentiated Cells but Not for the Down-regulation of Putative Targets during Differentiation

摘要: Micro-RNAs are small non-coding RNAs that regulate target gene expression post-transcriptionally through base pairing with the messenger RNA. Functional characterization of micro-RNAs awaits robust experimental methods to knock-down a micro-RNA as well assay its function in vivo. In addition recently developed method sequester 2′-O-methyl antisense oligonucleotide, we report interfering RNA against loop region precursor can be used deplete micro-RNA. The depletion miR-125b by this had profound effect on proliferation adult differentiated cancer cells, and defect was rescued co-transfected mature This technique has unique advantages over oligonucleotide determine function, vivo, identify contribution predicted pool given cell. let-7 induced, whereas their putative targets, lin-28 lin-41, decreased during vitro differentiation Tera-2 or embryonic stem cells. Experimental increase decrease concentrations did not, however, affect levels finding is explained fact down-regulation targets appears mostly at transcriptional level these systems. Collectively results reveal importance strategies for directly determining