beta 2-Syntrophin: localization at the neuromuscular junction in skeletal muscle.
The syntrophins are a multigene family of proteins which bind C-terminal domains of dystrophin, utrophin and homologs thereof. We report here that antibodies specific for one isoform, beta 2-syntrophin, labeled only the neuromuscular junction (NMJ) in rat skeletal muscle. Anti-alpha 1-syntrophin antibodies gave strong labeling of the sarcolemma and NMJ in normal rat and mouse muscle, and similar but much weaker labeling in dystrophin-minus mdx muscle. beta 2-Syntrophin therefore appears to be specific to the NMJ in normal muscle, as is utrophin, and may be involved in acetylcholine receptor clustering. alpha 1-Syntrophin appears to be associated mainly with dystrophin, as expected, but a small portion must be associated with another protein, possibly homologs of the electric tissue 87K protein.
Peters
M F
MF
Department of Physiology, University of North Carolina, Chapel Hill 27599-7545.
Kramarcy
N R
NR
Sealock
R
R
Froehner
S C
SC
D000595:Amino Acid Sequence; D000818:Animals; D003598:Cytoskeletal Proteins / Q000378:metabolism; D016189:Dystrophin / Q000378:metabolism; D049029:Dystrophin-Associated Proteins; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000294:innervation / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D049411:Utrophin
D003598:Cytoskeletal Proteins; D016189:Dystrophin; D049029:Dystrophin-Associated Proteins; D008565:Membrane Proteins; D009124:Muscle Proteins; C483600:Utrn protein, mouse; D049411:Utrophin; C091824:syntrophin