Essential role for Notch signaling in restricting developmental plasticity

Department of Molecular, Cellular, and Developmental Biology, Neuroscience Research Institute, University of California at Santa Barbara, Santa Barbara, California 93106, USA.
Genes & development (Impact Factor: 10.8). 11/2012; 26(21):2386-91. DOI: 10.1101/gad.199588.112
Source: PubMed


We report that Notch signaling is essential for the switch from developmental plasticity to commitment during Caenorhabditis elegans embryogenesis. The GLP-1 and LIN-12 Notch receptors act to set a memory state that affects commitment of cells arising from the major ectodermal progenitor (AB blastomere) several cell divisions later, thereby preventing their forced reprogramming by an endoderm-determining transcription factor. In contrast to Notch-dependent cell fate induction, this activity is autonomous to the AB lineage, is independent of the known cell fate-inducing Notch ligands, and requires a putative secreted Notch ligand, Delta Serrate Lag-3 (DSL-3). Thus, Notch signaling promotes developmental commitment by a mechanism that is distinct from that involved in specifying cell fates.

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Available from: Nareg Djabrayan, Feb 04, 2015
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