Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-7-12
pubmed:abstractText
Differentiation of the postsynaptic membrane at the neuromuscular junction requires agrin, a nerve-derived signal; MuSK, a critical component of the agrin receptor in muscle; and rapsyn, a protein that interacts with acetylcholine receptors (AChRs). We showed previously that nerve-induced AChR aggregation is dramatically impaired in knockout mice lacking agrin, MuSK, or rapsyn. However, the phenotypes of these mutants differed in several respects, suggesting that the pathway from agrin to MuSK to rapsyn is complex. Here, we compared the effects of these mutations on two aspects of synaptic differentiation: AChR clustering and transcriptional specialization of synapse-associated myonuclei. First, we show that a plant lectin, VVA-B4, previously shown to act downstream of agrin, can induce AChR clusters on MuSK-deficient but not rapsyn-deficient myotubes in culture. Thus, although both MuSK and rapsyn are required for AChR clustering in vivo, only rapsyn is essential for cluster formation per se. Second, we show that neuregulin, a nerve-derived inducer of AChR gene expression, activates AChR gene expression in cultured agrin- and MuSK-deficient myotubes, even though synapse-specific transcriptional specialization is disrupted in agrin and MuSK mutants in vivo. We propose that agrin works through MuSK to determine a synaptogenic region within which synaptic differentiation occurs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0165-3806
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Elsevier Science B.V.
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
114
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
171-8
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:10320756-Agrin, pubmed-meshheading:10320756-Animals, pubmed-meshheading:10320756-Cells, Cultured, pubmed-meshheading:10320756-Crosses, Genetic, pubmed-meshheading:10320756-Heterozygote, pubmed-meshheading:10320756-Mice, pubmed-meshheading:10320756-Mice, Inbred C57BL, pubmed-meshheading:10320756-Mice, Inbred CBA, pubmed-meshheading:10320756-Mice, Inbred Strains, pubmed-meshheading:10320756-Mice, Knockout, pubmed-meshheading:10320756-Mice, Transgenic, pubmed-meshheading:10320756-Muscle, Skeletal, pubmed-meshheading:10320756-Muscle Fibers, Skeletal, pubmed-meshheading:10320756-Muscle Proteins, pubmed-meshheading:10320756-Mutagenesis, pubmed-meshheading:10320756-Phenotype, pubmed-meshheading:10320756-Receptors, Cholinergic, pubmed-meshheading:10320756-Receptors, Growth Factor, pubmed-meshheading:10320756-Receptors, Nicotinic, pubmed-meshheading:10320756-beta-Galactosidase
pubmed:year
1999
pubmed:articleTitle
Distinct phenotypes of mutant mice lacking agrin, MuSK, or rapsyn.
pubmed:affiliation
Department of Molecular Biology and Pharmacology, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, MO 63110, USA. mgautam@slu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.