Abstract
BackgroundLack of appropriate tools and techniques to study fate and functional integration of newly generated neurons has so far hindered understanding of neurogenesis' relevance under physiological and pathological conditions. Current analyses are either dependent on mitotic labeling, for example BrdU-incorporation or retroviral infection, or on the detection of transient immature neuronal markers. Here, we report a transgenic mouse model (DCX-CreERT2) for time-resolved fate analysis of newly generated neurons. This model is based on the expression of a tamoxifen-inducible Cre recombinase under the control of a doublecortin (DCX) promoter, which is specific for immature neuronal cells in the CNS.ResultsIn the DCX-CreERT2 transgenic mice, expression of CreERT2 was restricted to DCX+ cells. In the CNS of transgenic embryos and adult DCX-CreERT2 mice, tamoxifen administration caused the transient translocation of CreERT2 to the nucleus, allowing for the recombination of loxP-flanked sequences. In our system, tamoxifen administration at E14.5 resulted in reporter gene activation throughout the developing CNS of transgenic embryos. In the adult CNS, neurogenic regions were the primary sites of tamoxifen-induced reporter gene activation. In addition, reporter expression could also be detected outside of neurogenic regions in cells physiologically expressing DCX (e.g. piriform cortex, corpus callosum, hypothalamus). Four weeks after recombination, the vast majority of reporter-expressing cells were found to co-express NeuN, revealing the neuronal fate of DCX+ cells upon maturation.ConclusionsThis first validation demonstrates that our new DCX-CreERT2 transgenic mouse model constitutes a powerful tool to investigate neurogenesis, migration and their long-term fate of neuronal precursors. Moreover, it allows for a targeted activation or deletion of specific genes in neuronal precursors and will thereby contribute to unravel the molecular mechanisms controlling neurogenesis.
Highlights
Lack of appropriate tools and techniques to study fate and functional integration of newly generated neurons has so far hindered understanding of neurogenesis’ relevance under physiological and pathological conditions
Transgenic models have been generated based on cell-type specific promoters such as nestin, GLAST, PLP, or DCX to investigate the biology of neural stem cells, radial glia, oligodendroglial precursors and neuronal precursors, respectively [11,17,18,19,20,21]
Generation of transgenic Dcx-CreERT2 mice We previously demonstrated that a 3509-bp DCX genomic fragment could properly drive expression of reporter genes in neuronal precursors and immature neurons in vitro and in vivo [9,10]
Summary
Lack of appropriate tools and techniques to study fate and functional integration of newly generated neurons has so far hindered understanding of neurogenesis’ relevance under physiological and pathological conditions. We report a transgenic mouse model (DCX-CreERT2) for time-resolved fate analysis of newly generated neurons This model is based on the expression of a tamoxifen-inducible Cre recombinase under the control of a doublecortin (DCX) promoter, which is specific for immature neuronal cells in the CNS. Transgenic models have been generated based on cell-type specific promoters such as nestin, GLAST, PLP (proteolipid protein), or DCX to investigate the biology of neural stem cells, radial glia, oligodendroglial precursors and neuronal precursors, respectively [11,17,18,19,20,21] These reporter mice are not suitable for long-term studies such as fate tracing or studies on the long-term functional integration of the newly generated neurons. The lack of suitable models to study neuronal precursors’ long-term fate still constitutes a major deficit
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.
