The function of microRNAs (miRNAs) is translational repression or mRNA cleavage of target genes by binding to 3¢-UTRs of target mRNA. In this study, we investigated the functions and the target genes of micro-RNA124a (miR124a), and imaged the miR124a-mediated repression of chromosome 14 open reading frame24(c14orf24, unknown function) during neurogenesis, using noninvasive luciferase systems.