The production of somatostatin interneurons in the olfactory bulb is regulated by the transcription factor sp8.

• Main Authors: Xuhua Jiang, Mingguang Zhang, Yan You, Fang Liu
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2013-01-01
• Series: PLoS ONE
• Online Access: http://europepmc.org/articles/PMC3720950?pdf=render

Somatostatin (Som), one of the most concentrated neuropeptides in the brain, is highly expressed in the olfactory bulb (OB). However, the temporal profile by which OB somatostatin-expressing (Som+) interneurons are produced and the molecular mechanisms controlling this profile are totally unknown. In the present study, we found that all the Som+ interneurons in the mouse external plexiform layer (EPL) and the rat glomerular layer (GL) express the transcription factor Sp8.Using the 5-bromo-2'-deoxyuridine (BrdU) birth dating method, combined with immunostaining, we showed that the generation of Som+ interneurons in the mouse and rat OB is confined to the later embryonic and earlier postnatal stages. Within the mouse OB, the production of Som+ interneurons is maximal during late embryogenesis and decreases after birth, whereas the generation of Som+ interneurons is low during embryogenesis and increases gradually after birth in the rat OB. Interestingly, genetic ablation of Sp8 by cre/loxP-based recombination severely reduces the number of Som+ interneurons in the EPL of the mouse OB. Taken together, these results suggest that Sp8 is required for the normal production of Som+ interneurons in the EPL of the mouse OB.