The vomeronasal organ (VNO) of rodents contains Gαi2 + and Gαo + vomeronasal sensory neurons (VSNs) as the two major neuronal types. Gαo-expressing VSNs localize to the basal portion of the vomeronasal epithelium (basal VSNs), while Gαi2-expressing VSNs localize to the apical territories (apical VSNs). Basal and apical VSNs are continuously formed starting from a common pool of Achaete Scute-like-1 (Ascl-1)-positive neural progenitor cells. However, how the apical or basal cell fate of the VSNs is established has not been fully addressed thus far. By combining single-cell sequencing and mouse genetics we discovered that active Notch signaling plays a pivotal in triggering the Gαo/basal differentiation program. Conversely, Notch signaling loss-of-function prevents the formation of Gαo/basal VSNs. In this presentation, I will illustrate the basic mechanisms controlling the differentiation dichotomy of the vomeronasal sensory neurons. Moreover, I will share some of our new findings about the molecular mechanisms controlling the maturation of the VSNs after the differentiation dichotomy is established.

This research is supported by the National Institute of Deafness and Other Communication Disorders of the National Institutes of Health under the Award R01-DC017149.