title: Notch signaling inhibits axon regeneration.
abstract: Many neurons have limited capacity to regenerate their axons after injury. Neurons in the mammalian central nervous system do not regenerate, and even neurons in the peripheral nervous system often fail to regenerate to their former targets. This failure is likely due in part to pathways that actively restrict regeneration; however, only a few factors that limit regeneration are known. Here, using single-neuron analysis of regeneration in vivo, we show that Notch/lin-12 signaling inhibits the regeneration of mature C. elegans neurons. Notch signaling suppresses regeneration by acting autonomously in the injured cell to prevent growth cone formation. The metalloprotease and gamma-secretase cleavage events that lead to Notch activation during development are also required for its activity in regeneration. Furthermore, blocking Notch activation immediately after injury improves regeneration. Our results define a postdevelopmental role for the Notch pathway as a repressor of axon regeneration in vivo.
authors.affiliation: Department of Genetics, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06510, USA.
authors.forename: Rachid
authors.initials: R
authors.lastname: El Bejjani
authors.forename: Marc
authors.initials: M
authors.lastname: Hammarlund
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism*; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism*; D020439:Growth Cones / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D009416:Nerve Regeneration / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D051880:Receptors, Notch / Q000378:metabolism*; D020127:Recovery of Function / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D029742:Caenorhabditis elegans Proteins; C082460:Lin-12 protein, C elegans; D008565:Membrane Proteins; D051880:Receptors, Notch