title: Olfactory sensory neuron-specific and sexually dimorphic expression of protocadherin 20.
abstract: Olfactory sensory axons navigate from the nasal cavity to the olfactory bulb and sort from among 1,000 different odorant receptor-expressing types to converge upon the same two or three glomeruli. To achieve this task during development, it is likely that multiple classes of regulatory molecules, including cell adhesion molecules, are involved. Cell adhesion molecules have been shown to be important in controlling axon guidance, fasciculation, and synapse formation. To gain further understanding of the involvement of adhesion molecules in olfactory circuitry development, we examined the dynamic and cell type specific expression of a novel protocadherin, PCDH20, in the olfactory system. PCDH20 is specifically expressed in newly differentiated olfactory sensory neurons and their axons during development. PCDH20 expression is down-regulated in the adult olfactory system, except in a small olfactory sensory neuron population. These small, discrete numbers of PCDH20-positive glomeruli in the adult olfactory bulb are consistently clustered in the ventral-caudal region in both male and female mice. However, adult males have higher numbers of PCDH20-positive glomeruli with a broader distribution, whereas adult females have fewer PCDH20-positive glomeruli with a more restricted distribution. The gender difference in PCDH20 expression may reflect olfactory receptor expression differences for gender-specific social discrimination.
authors: Department of Cell Biology and Human Anatomy, University of California at Davis, School of Medicine, Davis, California 95616, USA.
authors: Wooje
authors: W
authors: Lee
authors: Ting-Wen
authors: TW
authors: Cheng
authors: Qizhi
authors: Q
authors: Gong
mesh_terms: D000367:Age Factors; D000818:Animals; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D015536:Down-Regulation / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009475:Neurons, Afferent / Q000378:metabolism*; D009830:Olfactory Bulb / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D018034:Olfactory Receptor Neurons / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism; D000091363:Protocadherins; D012333:RNA, Messenger / Q000378:metabolism; D012727:Sex Characteristics; D019147:Vomeronasal Organ / Q000166:cytology / Q000254:growth & development / Q000502:physiology
chemical_list: D015820:Cadherins; D009419:Nerve Tissue Proteins; C527873:PCDH20 protein, mouse; D000091363:Protocadherins; D012333:RNA, Messenger