Functional analysis of microRNAs during the retinoic acid-induced neuronal differentiation of human NT2 cells. Nucleic Acids Res Suppl, 243-244. (suppl volume

MicroRNAs (miRNAs) are phylogenetically widespread small RNAs in animals and plants. These small RNAs can regulate a gene expression at a translational level and play roles during the development of C. elegans, D. melanogaster and plants. Although more than two hundred miRNAs have been found in mammals, the target mRNAs of miRNAs is unknown. Recently, we identified Hesl, bHLH transcriptional repressor, as a target of miR-23 in NT2 cells. In this study, we further investigate that the expression of Hesl is regulated by miR-23 during the retinoic acid (RA)-induced neural differentiation of NT2 cells. Reduction in the level of miR-23 by siRNAs resulted in the accumulation of Hesl in differentiated NT2 cells. Moreover, a reduction in the level of miR-23 by siRNA-miR-23 affected the RA-induced neural differentiation of NT2 cells. Thus, our results indicate that miR-23 has a critical role in the RA-induced neuronal differentiation of NT2 cells