Synapses form in skeletal muscles lacking neuregulin receptors.
The formation of the neuromuscular junction (NMJ) is directed by reciprocal interactions between motor neurons and muscle fibers. Neuregulin (NRG) and Agrin from motor nerve terminals are both implicated. Here, we demonstrate that NMJs can form in the absence of the NRG receptors ErbB2 and ErbB4 in mouse muscle. Postsynaptic differentiation is, however, induced by Agrin. We therefore conclude that NRG signaling to muscle is not required for NMJ formation. The effects of NRG signaling to muscle may be mediated indirectly through Schwann cells.
Escher
P
P
Institute of Physiology, Biozentrum, University of Basel, 4056 Basel, Switzerland.
Lacazette
E
E
Courtet
M
M
Blindenbacher
A
A
Landmann
L
L
Bezakova
G
G
Lloyd
K C
KC
Mueller
U
U
Brenner
H R
HR
D018171:Agrin / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D066246:ErbB Receptors / Q000235:genetics / Q000502:physiology*; D018815:Genes, erbB; D018734:Genes, erbB-2; D008564:Membrane Potentials; D051379:Mice; D009045:Motor Endplate / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D018482:Muscle, Skeletal / Q000294:innervation* / Q000648:ultrastructure; D009154:Mutation; D020880:Neuregulins / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000196:embryology / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D017729:Presynaptic Terminals / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000502:physiology*; D066247:Receptor, ErbB-4; D011950:Receptors, Cholinergic / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D012583:Schwann Cells / Q000502:physiology; D015398:Signal Transduction; D009435:Synaptic Transmission
D018171:Agrin; D066246:ErbB Receptors; D020880:Neuregulins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D066247:Receptor, ErbB-4; D011950:Receptors, Cholinergic; C587690:Erbb4 protein, mouse