Ryks: new partners for Wnts in the developing and regenerating nervous system.
Conserved Ryk transmembrane proteins, tyrosine kinase-related Wnt receptors, are important during neurogenesis, axon guidance and synaptogenesis. Here, we review the increasingly complex biology of the Wnt/Ryk pathway, emphasizing the mechanisms by which Ryks transduce or sometimes block the Wnt signal. Recent studies reveal that Wnts signal through Ryk via multiple mechanisms, including nuclear translocation of their intracellular domains and pathways employing Src Family Kinases and members of the canonical Wnt pathway. We also discuss reports indicating that Wnt/Ryk axon guidance roles are evolutionarily conserved and Wnt/Ryk interactions are required for motoneuron target selection and synaptogenesis at the neuromuscular junction. Recent findings that injury-induced Wnt/Ryk pathway activation inhibits axon regeneration underscore the importance of further understanding this novel pathway.
Fradkin
Lee G
LG
Department of Molecular Cell Biology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands. L.G.Fradkin@lumc.nl
Dura
Jean-Maurice
JM
Noordermeer
Jasprina N
JN
D000818:Animals; D001369:Axons / Q000502:physiology; D006801:Humans; D009416:Nerve Regeneration / Q000502:physiology*; D009420:Nervous System / Q000378:metabolism*; D055495:Neurogenesis / Q000502:physiology; D009469:Neuromuscular Junction / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013569:Synapses / Q000502:physiology; D051153:Wnt Proteins / Q000378:metabolism*
D051153:Wnt Proteins; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases