Hairy is a cell context signal controlling Notch activity.
Notch signaling regulates cell fate determination and many developmental processes. Here we report that lateral inhibition, a major mechanism for Notch activity, is modulated by Hairy, a bHLH-WRPW protein. In Xenopus, Notch can have from inhibitory, permissive to enhancing roles in muscle or neural differentiation. These cell context-dependent effects correlate with Hairy expression levels from high to low, respectively, in the cells. Moreover, Notch effects can be altered upon manipulation of Hairy expression. We propose that Hairy provides a cell context in which a cell can interpret Notch and other extrinsic signals by controlling responsiveness of its target genes; this mode of Hairy-Notch interaction may apply in other systems.
Cui
Yanzhen
Y
Department of Environmental and Biomolecular Systems, Oregon Graduate Institute School of Science and Engineering, Oregon Health and Science University, 20000 NW Walker Road, Beaverton, OR 97006, USA. cuiy@ebs.ogi.edu
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D004475:Ectoderm / Q000166:cytology / Q000378:metabolism; D024510:Muscle Development / Q000187:drug effects; D009154:Mutation; D017570:MyoD Protein / Q000378:metabolism; D051880:Receptors, Notch / Q000187:drug effects / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D014981:Xenopus / Q000196:embryology; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D051792:Basic Helix-Loop-Helix Proteins; D017570:MyoD Protein; D051880:Receptors, Notch; D012097:Repressor Proteins; D029867:Xenopus Proteins; C504431:Esr1 protein, Xenopus; C439928:HES4 protein, Xenopus