5HTR3A-driven GFP labels immature olfactory sensory neurons.
The ionotropic serotonin receptor, 5-HT3, is expressed by many developing neurons within the central nervous system. Since the olfactory epithelium continues to generate new olfactory sensory neurons (OSNs) throughout life, we investigated the possibility that 5-HT3is expressed in the adult epithelium. Using a transgenic mouse in which the promoter for the 5-HT3asubunit drives expression of green fluorescent protein (GFP), we assessed the expression of this marker in the olfactory epithelium of adult mice. Both the native 5-HT3amRNA and GFP are expressed within globose basal cells of the olfactory and vomeronasal epithelium in adult mice. Whereas the 5-HT3amRNA disappears relatively quickly after final cell division, the GFP label persists for about 5 days, thereby labeling immature OSNs in both the main olfactory system and vomeronasal organ. The GFP-labeled cells include both proliferative globose basal cells as well as immature OSNs exhibiting the hallmarks of ongoing differentiation including GAP43, PGP9.5, but the absence of olfactory marker protein. Some of the GFP-labeled OSNs show characteristics of more mature yet still developing OSNs including the presence of cilia extending from the apical knob and expression of NaV1.5, a component of the transduction cascade. These findings suggest that 5-HT3ais indicative of a proliferative or developmental state, regardless of age, and that the 5-HT3AGFP mice may prove useful for future studies of neurogenesis in the olfactory epithelium. J. Comp. Neurol. 525:1743-1755, 2017. © 2016 Wiley Periodicals, Inc.
Department of Cell and Developmental Biology, Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado.|Program in Neuroscience, University of Colorado School of Medicine, Aurora, Colorado.
Thomas E
http://orcid.org/0000-0001-5923-5099
TE
Finger
Department of Cell and Developmental Biology, Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado.|Program in Neuroscience, University of Colorado School of Medicine, Aurora, Colorado.|Departments of Neurosurgery and Neuroscience, Yale University School of Medicine, New Haven, Connecticut.
Dianna L
DL
Bartel
Department of Cell and Developmental Biology, Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado.
Nicole
N
Shultz
Department of Cell and Developmental Biology, Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado.|Program in Neuroscience, University of Colorado School of Medicine, Aurora, Colorado.
Noah B
NB
Goodson
Departments of Neurosurgery and Neuroscience, Yale University School of Medicine, New Haven, Connecticut.|Interdepartmental Neuroscience Graduate Program, Yale University, New Haven, Connecticut.
Charles A
CA
Greer
D053687:Adult Stem Cells / Q000166:cytology; D000818:Animals; D049452:Green Fluorescent Proteins; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008822:Mice, Transgenic; D046529:Microscopy, Electron, Transmission; D058953:Neural Stem Cells / Q000166:cytology* / Q000378:metabolism; D055495:Neurogenesis / Q000502:physiology*; D018034:Olfactory Receptor Neurons / Q000166:cytology*; D044406:Receptors, Serotonin, 5-HT3 / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D044406:Receptors, Serotonin, 5-HT3; D049452:Green Fluorescent Proteins
GAP43; OMP; RRID: AB_10000240; RRID: AB_177503; RRID: AB_2107282; RRID: AB_2314700; RRID: AB_2315774; RRID: AB_2336231; RRID: AB_2336819; RRID: AB_2340375; RRID: AB_2532919; RRID: AB_2534013; RRID: AB_2534017; RRID: AB_310177; RRID: AB_477413; RRID: AB_796160; neurogenesis; olfactory; serotonin; vomeronasal