XB-ART-42435Nucleic Acids Res. April 1, 2011; 39 (7): 2869-79.
MiR-124 regulates early neurogenesis in the optic vesicle and forebrain, targeting NeuroD1.
MicroRNAs (miRNAs) are involved in the fine control of cell proliferation and differentiation during the development of the nervous system. MiR-124, a neural specific miRNA, is expressed from the beginning of eye development in Xenopus, and has been shown to repress cell proliferation in the optic cup, however, its role at earlier developmental stages is unclear. Here, we show that this miRNA exerts a different role in cell proliferation at the optic vesicle stage, the stage which precedes optic cup formation. We show that miR-124 is both necessary and sufficient to promote cell proliferation and repress neurogenesis at the optic vesicle stage, playing an anti-neural role. Loss of miR-124 upregulates expression of neural markers NCAM, N-tubulin while gain of miR-124 downregulates these genes. Furthermore, miR-124 interacts with a conserved miR-124 binding site in the 3''-UTR of NeuroD1 and negatively regulates expression of the proneural marker NeuroD1, a bHLH transcription factor for neuronal differentiation. The miR-124-induced effect on cell proliferation can be antagonized by NeuroD1. These results reveal a novel regulatory role of miR-124 in neural development and uncover a previously unknown interaction between NeuroD1 and miR-124.
PubMed ID: 21131276
PMC ID: PMC3074159
Article link: Nucleic Acids Res.
Genes referenced: ctrl elavl3 lhx2 mut ncam1 neurod1 odc1 pax6 tdrd6 tubb2b twist1
Article Images: [+] show captions
|Figure 6. A putative scheme of the regulatory effect of miR-124 on NeuroD1 in early eye and brain development. NeuroD1, which represses cell proliferation and promotes neuronal differentiation, is one of the target genes of miR-124. The arrow represents promotion; the right angle represents repression.|