| First Author | Gustus KC | Year | 2018 |
| Journal | Hippocampus | Volume | 28 |
| Issue | 10 | Pages | 735-744 |
| PubMed ID | 29995325 | Mgi Jnum | J:284899 |
| Mgi Id | MGI:6392537 | Doi | 10.1002/hipo.23008 |
| Citation | Gustus KC, et al. (2018) Genetic inactivation of synaptosomal-associated protein 25 (SNAP-25) in adult hippocampal neural progenitors impairs pattern discrimination learning but not survival or structural maturation of newborn dentate granule cells. Hippocampus 28(10):735-744 |
| abstractText | Adult neurogenesis is necessary for proper cognition and behavior, however, the mechanisms that underlie the integration and maturation of newborn neurons into the pre-existing hippocampal circuit are not entirely known. In this study, we sought to determine the role of action potential (AP)-dependent synaptic transmission by adult-generated dentate granule cells (DGCs) in their survival and function within the existing circuitry. We used a triple transgenic mouse (NestinCreER(T2) :Snap25(fl/fl) : tdTomato) to inducibly inactivate AP-dependent synaptic transmission within adult hippocampal progenitors and their progeny. Behavioral testing in a hippocampal-dependent A/B contextual fear-discrimination task revealed impaired discrimination learning in mice harboring SNAP-25-deficient adult-generated dentate granule cells (DGCs). Despite poor performance on this neurogenesis-dependent task, the production and survival of newborn DGCs was quantitatively unaltered in tamoxifen-treated NestinCreER(T2) :Snap25(fl/fl) : tdTomato SNAP compared to tamoxifen-treated NestinCreER(T2) :Snap25(wt/wt) : tdTomato control mice. Although SNAP-25-deficient adult DGCs displayed a small but statistically significant enhancement in proximal dendritic branching, their overall dendritic length and distal branching complexity was unchanged. SNAP-25-deficient newborn DGCs also displayed robust efferent mossy fiber output to CA3, with normal linear density of large mossy fiber terminals (LMTs). These studies suggest that AP-dependent neurotransmitter release by newborn DGCs is not essential for their survival or rudimentary structural maturation within the adult hippocampus. |
