Abstract
Olfactory bulb (OB) neurogenesis generates neurons that use GABA or dopamine as their neurotransmitters throughout life. Regionalized stem cell populations in the periventricular zone (PVZ) of the lateral ventricles (LVs) have been shown to be at the basis of neuronal diversity in the system. For example dopaminergic neurons arise predominantly from neural stem cells (NSCs) residing in the dorsal PVZ and depend on the expression of the transcription factors Pax6 and Dlx2 for their specification. In addition, Dlx2 is required for neurogenesis in general. Using targeted in vivo electroporation combined with immuno-fluorescence imaging and microarray analysis, we provide here detailed spatial and temporal expression data with cellular resolution in this system. We find that all along the neurogenic process Pax6 expression remains restricted to the dorsal PVZ, whereas nearly all neuroblasts express Dlx2, including those of the dorsal lineage, which are switched on for Dlx2 when they enter the rostral migratory stream (RMS). These data allow to explain and precise the functions of these two genes in postnatal OB neurogenesis.
Highlights
Neurogenesis persists in the postnatal and adult mouse olfactory bulb (OB)
To analyze the time course and extent of Pax6 expression in the dorsal periventricular zone (PVZ) we used in vivo electroporation
This technique allows discriminating dorsally vs. laterally generated cells in the rostral migratory stream (RMS) and OB, these cells are intermingled in both structures
Summary
Neurogenesis persists in the postnatal and adult mouse olfactory bulb (OB). In this system, neuroblasts are generated in the periventricular zone (PVZ) of the lateral ventricles (LVs). After a phase of amplification they migrate along the rostral migratory stream (RMS) to differentiate into OB interneurons that play a major role in olfactory function (Lledo et al, 2006). The newly generated interneurons in the OB present a large diversity of phenotypes. It has been shown that this phenotypic diversity relies on the spatial distribution of the corresponding neural stem cells (NSCs) in the germinal zone, the PVZ (Merkle et al, 2007). It has been recently shown that Shh signaling in the most ventral part of PVZ controls differentiation of a particular OB neuronal subtype that is characterized by calbindin expression (Ihrie et al, 2011)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
