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


Publication Type:

Source:

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

Keywords:

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

Abstract:

<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>