Notch1 and its ligands Delta-like and Jagged are expressed and active in distinct cell populations in the postnatal mouse brain.
Notch signaling plays a pivotal role in the regulation of vertebrate neurogenesis. However, in vitro experiments suggest that Notch1 may also be involved in the regulation of later stages of brain development. We have addressed putative roles in the central nervous system by examining the expression of Notch signaling cascade components in the postnatal mouse brain. In situ mRNA hybridization revealed that Notch1 is associated with cells in the subventricular zone, the dentate gyrus and the rostromigratory stream, all regions of continued neurogenesis in the postnatal brain. In addition, Notch1 is expressed at low levels throughout the cortex and olfactory bulb and shows striking expression in the cerebellar Purkinje cell layer. The Notch ligands, including Delta-like1 and 3 and Jagged1 and Jagged2, show distinct expression patterns in the developing and adult brain overlapping that of Notch1. In addition, the downstream targets of the Notch signaling cascade Hes1, Hes3, Hes5 and the intrinsic Notch regulatory proteins Numb and Numblike also show active signaling in distinct brain regions. Hes5 coincides with the majority of Notch1 expression and can be detected in the cerebral cortex, cerebellum and putative germinal zones. Hes3, on the other hand, shows a restricted expression in cerebellar Purkinje cells. The distribution of Notch1 and its putative ligands suggest distinct roles in specific subsets of cells in the postnatal brain including putative stem cells and differentiated neurons.
Stump
Gila
G
Institute of Cell Biology, Department of Biology, Swiss Federal Institute of Technology, CH-8093 Zurich, Switzerland.
Durrer
André
A
Klein
Anne-Laurence
AL
Lütolf
Simone
S
Suter
Ueli
U
Taylor
Verdon
V
D000818:Animals; D001921:Brain / Q000196:embryology / Q000378:metabolism; D002135:Calcium-Binding Proteins; D002454:Cell Differentiation; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D000072100:Jagged-1 Protein; D000072101:Jagged-2 Protein; D008024:Ligands; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D009474:Neurons / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D000072099:Serrate-Jagged Proteins; D015398:Signal Transduction; D014157:Transcription Factors
D002135:Calcium-Binding Proteins; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; C000606274:Jag1 protein, mouse; C490503:Jag2 protein, mouse; D000072100:Jagged-1 Protein; D000072101:Jagged-2 Protein; D008024:Ligands; D008565:Membrane Proteins; C497762:Notch1 protein, mouse; D012333:RNA, Messenger; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D000072099:Serrate-Jagged Proteins; D014157:Transcription Factors; C064045:delta protein