Abstract:
During the development of the mammalian Central Nervous System (CNS), neurons undergo morphological changes in response to different sensory experiences to maintain proper neuronal networks (Zillies, 1992; Fuchs and Flügge, 2014). Previous research from our lab has identified Rem2, a member of the RGK family of small Ras-like GTPases, as an activity-regulated gene important for regulating neuronal morphology. Specifically, knockdown of Rem2 results in a decreased number of dendritic spines but an increased number of dendritic branches, suggesting that Rem2 is both a positive regulator of synapse formation and a negative regulator of dendritic complexity (Ghiretti and Paradis, 2011; Moore et al. 2013). The goal of this study was to elucidate the role of Rem2 in vivo and determine the relationship between neuronal activity, Rem2 and its effects on neuronal morphology. Our findings show that Rem2 is not an important factor in regulating both dendritic complexity and dendritic spine formation in vivo. However, by manipulating sensory experience through dark rearing, we found that activity is important for spine distribution and causes a significant increase in spine density of wildtype mice at more distal regions along the dendrite.