Notch 2 and Notch 1/3 segregate to neuronal and glial lineages of the developing olfactory epithelium.
The murine olfactory epithelium (OE) generates olfactory receptor neurons (ORNs) throughout development and into adulthood, but only a few of the factors regulating olfactory neuro- and glio-genesis have been delineated. Notch receptors maintain CNS neuronal progenitors and drive glial differentiation, and the Notch effectors Hes 1 and 5 are expressed in the OE, but the Notch receptors that stimulate Hes gene activation in defined lineages during OE development have not been determined. Here, we first use RT-PCR to reveal which Notch receptors and ligands are expressed in the developing and adult OE. This is followed by immunofluorescent detection, combined with lineage-specific markers to define the stage-specific developmental expression of different Notch family members. We show that throughout development, Notch 1 and 3 are expressed in cells retained within the lamina propria, where Notch 3 is expressed in olfactory ensheathing cells (OECs). In contrast, Notch 2 is expressed in apical embryonic and early postnatal OE neuronal progenitors. In postnatal and adult OE, Notch 1 is expressed predominantly in Bowman's glands, and Notch 2 in sustentacular cells. Notch 2 and Notch 1/3 may, therefore, have different roles in the commitment and differentiation of neuronal and glial lineages of the OE during development, and the maintenance of non-neuronal phenotypes postnatally.
Carson
Christine
C
Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
Murdoch
Barbara
B
Roskams
A Jane
AJ
D000818:Animals; D019070:Cell Lineage / Q000502:physiology*; D051379:Mice; D009457:Neuroglia / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D009831:Olfactory Mucosa / Q000166:cytology / Q000196:embryology*; D051881:Receptor, Notch1 / Q000378:metabolism*; D051883:Receptor, Notch2 / Q000378:metabolism*; D000071656:Receptor, Notch3; D051880:Receptors, Notch / Q000378:metabolism*
C497762:Notch1 protein, mouse; C497765:Notch2 protein, mouse; C499373:Notch3 protein, mouse; D051881:Receptor, Notch1; D051883:Receptor, Notch2; D000071656:Receptor, Notch3; D051880:Receptors, Notch