The Neurotrophin Receptor TrkC Contributes to the Development of Diverse Olfactory Bulb Neurons

In mammals, expression of the neurotrophin receptor TrkC begins during early brain development and is present in almost all brain structures. In the olfactory bulb, TrkC expression appears with the generation of the first neurons. Here, we examine the role of TrkC receptors in the development of distinct olfactory bulb cell types in the opossum Monodelphis domestica. We determine that mitral/tufted projecting cells are generated on postnatal days (P) 1-5 and later, starting at P11, periglomerular and granule interneurons are developed. We found that TrkC signaling has no effect on the proliferation of early- and later-born neurons, but has a cell-specific effect on the growth of distinct olfactory bulb cells. Silencing of TrkC expression by shRNA affects the morphometric characteristics of projecting cells. Altogether, our findings show that TrkC signaling contributes to maintaining soma growth and dendritic complexity of projecting mitral/tufted neurons of the olfactory bulb.