ER81 and CaMKIV identify anatomically and phenotypically defined subsets of mouse olfactory bulb interneurons.
The mechanisms underlying dopamine (DA) phenotypic differentiation in the olfactory bulb (OB) have not yet been fully elucidated and are the subject of some controversy. OB DA interneurons destined for the glomerular layer were shown to originate in the subventricular zone (SVZ) and in the rostral migratory stream (RMS). The current study investigated whether calcium/calmodulin-dependent protein kinase IV (CaMKIV) either alone or together with the Ets transcription factor ER81 was necessary for phenotypic determination during migration of progenitors. In most brain areas, including the OB, CaMKIV and ER81 displayed a reciprocal distribution. In the SVZ, only ER81 could be demonstrated. In the RMS, a subpopulation of progenitors contained ER81, but few, if any, contained CaMKIV. In OB, CaMKIV expression, restricted to deep granule cells, showed limited overlap with ER81. ER81 expression was weak in deep granule cells. Strong labeling occurred in the mitral and glomerular layers, where ER81 colabeled dopaminergic periglomerular cells that expressed either tyrosine hydroxylase (TH) or green fluorescent protein, the latter reporter gene under control of 9-kb of 5' TH promoter. Odor deprivation resulted in a significant 5.2-fold decline in TH immunoreactivity, but ER81 exhibited a relatively small 1.7-fold decline in immunoreactivity. TH expression as well as brain and bulb size were unchanged in CaMKIV knockout mice. These data suggest that ER81 may be required but is not sufficient for DA neuron differentiation and that CaMKIV is not directly involved in TH gene regulation.
Saino-Saito
Sachiko
S
Department of Anatomy and Cell Biology, Yamagata University School of Medicine, Yamagata, Japan 990-9585.
Cave
John W
JW
Akiba
Yosuke
Y
Sasaki
Hayato
H
Goto
Kaoru
K
Kobayashi
Kazuto
K
Berlin
Roseann
R
Baker
Harriet
H
D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D054734:Calcium-Calmodulin-Dependent Protein Kinase Type 4; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004298:Dopamine / Q000096:biosynthesis; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D007150:Immunohistochemistry; D007395:Interneurons / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008822:Mice, Transgenic; D009830:Olfactory Bulb / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism*; D010641:Phenotype; D012683:Sensory Deprivation / Q000502:physiology; D012903:Smell / Q000502:physiology; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D013687:Telencephalon / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics / Q000378:metabolism
D015415:Biomarkers; D004268:DNA-Binding Proteins; C490641:Etv1 protein, mouse; D014157:Transcription Factors; D014446:Tyrosine 3-Monooxygenase; D054734:Calcium-Calmodulin-Dependent Protein Kinase Type 4; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C517685:Camk4 protein, mouse; D004298:Dopamine