Crosstalk between Agrin and Wnt signaling pathways in development of vertebrate neuromuscular junction.
Neuromuscular junction (NMJ) is a cholinergic synapse where motor neurons elicit muscle contraction. Agrin and its coreceptors LRP4 and MuSK are critical for vertebrate NMJ formation. This paper reviews recent evidence for Wnts and Wnt signaling molecules in NMJ formation including a possible retrograde mechanism by muscle β-catenin. We also present data that Wnt3a, 7a, 8a and 10b could inhibit agrin-mediated AChR clustering. Together with the stimulating effect of Wnt9a, 9b, 10b, 11 and 16 on AChR clustering in the absence of agrin, these results suggest diverse roles for Wnt ligands in NMJ development.
Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, Georgia, 30912.
Arnab
A
Barik
Bin
B
Zhang
Gurkirpal S
GS
Sohal
Wen-Cheng
WC
Xiong
Lin
L
Mei
D018171:Agrin / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D006801:Humans; D009469:Neuromuscular Junction / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism; D014714:Vertebrates / Q000378:metabolism*; D060449:Wnt Signaling Pathway / Q000502:physiology*
D018171:Agrin
LRP4; NMJ; WNT; aneural clusters; musk