RT Journal Article SR Electronic T1 Embryonic and postnatal neurogenesis produce functionally distinct subclasses of dopaminergic neuron JF bioRxiv FD Cold Spring Harbor Laboratory SP 196006 DO 10.1101/196006 A1 Elisa Galliano A1 Eleonora Franzoni A1 Marine Breton A1 Annisa N. Chand A1 Darren J. Byrne A1 Venkatesh N. Murthy A1 Matthew S. Grubb YR 2017 UL http://biorxiv.org/content/early/2017/09/29/196006.abstract AB Most neurogenesis in the mammalian brain is completed embryonically, but in certain areas the production of neurons continues throughout postnatal life. The functional properties of mature postnatally-generated neurons often match those of their embryonically-produced counterparts. However, we show here that in the olfactory bulb (OB), embryonic and postnatal neurogenesis produce functionally distinct subpopulations of dopaminergic (DA) neurons. We define two subclasses of OB DA neuron by the presence or absence of a key subcellular specialisation: the axon initial segment (AIS). Large AIS-positive axon-bearing DA neurons are exclusively produced during early embryonic stages, leaving small anaxonic AIS-negative cells as the only DA subtype generated via adult neurogenesis. These populations are functionally distinct: large DA cells are more excitable, yet display weaker and more broadly-tuned responses to odorant stimuli. Embryonic and postnatal neurogenesis can therefore generate distinct neuronal subclasses, placing important constraints on the functional roles of adult-born neurons in sensory processing.