Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
The proneural protein neurogenin (XNGNR1) drives differentiation of primary neurons in combination with the cyclin-dependent kinase (Cdk) inhibitor Xic1. Differentiation is inhibited by Notch signalling, resulting in a scattered neuronal distribution. Here we show that Notch signalling regulates the level of Xic1 transcription, yet this does not correlate with Notch's ability to perturb the cell cycle. Instead, Notch may regulate Xic1 levels to control its differentiation function directly, which is required in parallel with XNGNR1 to promote primary neurogenesis. Indeed, Notch-mediated repression of both XNGNR1 and Xic1 must be relieved for neuronal differentiation to occur. Interestingly, although Xic1 is required for XNGNR1-mediated neurogenesis, it is not required for XNGNR1-mediated upregulation of Delta, allowing establishment of the negative feedback loop involved in lateral inhibition. Therefore, Notch targets Cdk inhibitor expression to regulate differentiation of primary neurons, and its effects on the cell cycle may be of secondary importance.
Bashir,
Cdk1: the dominant sibling of Cdk2.
2005, Pubmed
Bashir,
Cdk1: the dominant sibling of Cdk2.
2005,
Pubmed
Bellefroid,
X-MyT1, a Xenopus C2HC-type zinc finger protein with a regulatory function in neuronal differentiation.
1996,
Pubmed
,
Xenbase
Castella,
HES-1 repression of differentiation and proliferation in PC12 cells: role for the helix 3-helix 4 domain in transcription repression.
2000,
Pubmed
Chitnis,
Primary neurogenesis in Xenopus embryos regulated by a homologue of the Drosophila neurogenic gene Delta.
1995,
Pubmed
,
Xenbase
Coffman,
Expression of an extracellular deletion of Xotch diverts cell fate in Xenopus embryos.
1993,
Pubmed
,
Xenbase
Coqueret,
New roles for p21 and p27 cell-cycle inhibitors: a function for each cell compartment?
2003,
Pubmed
Deblandre,
A two-step mechanism generates the spacing pattern of the ciliated cells in the skin of Xenopus embryos.
1999,
Pubmed
,
Xenbase
Kageyama,
Roles of bHLH genes in neural stem cell differentiation.
2005,
Pubmed
Lee,
Conversion of Xenopus ectoderm into neurons by NeuroD, a basic helix-loop-helix protein.
1995,
Pubmed
,
Xenbase
Ma,
Identification of neurogenin, a vertebrate neuronal determination gene.
1996,
Pubmed
,
Xenbase
Papalopulu,
A posteriorising factor, retinoic acid, reveals that anteroposterior patterning controls the timing of neuronal differentiation in Xenopus neuroectoderm.
1996,
Pubmed
,
Xenbase
Rangarajan,
Notch signaling is a direct determinant of keratinocyte growth arrest and entry into differentiation.
2001,
Pubmed
Saka,
Spatial and temporal patterns of cell division during early Xenopus embryogenesis.
2001,
Pubmed
,
Xenbase
Sarmento,
Notch1 modulates timing of G1-S progression by inducing SKP2 transcription and p27 Kip1 degradation.
2005,
Pubmed
Shimamura,
Wnt-1-dependent regulation of local E-cadherin and alpha N-catenin expression in the embryonic mouse brain.
1994,
Pubmed
Solecki,
Activated Notch2 signaling inhibits differentiation of cerebellar granule neuron precursors by maintaining proliferation.
2001,
Pubmed
Sriuranpong,
Notch signaling induces rapid degradation of achaete-scute homolog 1.
2002,
Pubmed
Su,
Cloning and characterization of the Xenopus cyclin-dependent kinase inhibitor p27XIC1.
1995,
Pubmed
,
Xenbase
Vernon,
The cdk inhibitor p27Xic1 is required for differentiation of primary neurones in Xenopus.
2003,
Pubmed
,
Xenbase
Wettstein,
The Xenopus homolog of Drosophila Suppressor of Hairless mediates Notch signaling during primary neurogenesis.
1997,
Pubmed
,
Xenbase