microRNA-125 distinguishes developmentally generated and adult-born olfactory bulb interneurons.

Publication Type:


Development, Volume 141, Issue 7, p.1580-8 (2014)


Adult Stem Cells, Animals, Animals, Newborn, Biological Markers, Cell Differentiation, Embryonic Stem Cells, Female, Interneurons, Male, Mice, Mice, Inbred C57BL, Mice, Transgenic, MicroRNAs, Neural Stem Cells, Neurogenesis, Olfactory Bulb, Synapses


<p>New neurons, originating from the subventricular zone, are continuously integrating into neuronal circuitry in the olfactory bulb (OB). Using a transgenic sensor mouse, we found that adult-born OB interneurons express microRNA-125 (miR-125), whereas the pre-existing developmentally generated OB interneurons represent a unique population of cells in the adult brain, without miR-125 activity. Stable inhibition of miR-125 in newborn OB neurons resulted in enhanced dendritic morphogenesis, as well as in increased synaptic activation in response to odour sensory stimuli. These data demonstrate that miR-125 controls functional synaptic integration of adult-born OB interneurons. Our results also suggest that absence of an otherwise broadly expressed miRNA is a novel mechanism with which to achieve neuronal subtype specification.</p>