Agrin mediates cell contact-induced acetylcholine receptor clustering.
One of the important events in synapse formation is the accumulation of neurotransmitter receptors beneath the presynaptic nerve terminal. Agrin is a component of the synaptic basal lamina that induces the clustering of acetylcholine receptors when bath-applied to muscle fibers in culture. When a cDNA encoding a putative agrin protein is transfected into cells, the molecule is secreted and concentrated on the extracellular surface. Coculture of transfected cells with muscle fibers induces the formation of receptor patches at contact sites. These results demonstrate that expression of a single gene encoding agrin confers receptor clustering that is restricted to specific sites of cell-muscle contact.
Campanelli
J T
JT
Department of Molecular and Cellular Physiology, Stanford University, California 94305.
Hoch
W
W
Rupp
F
F
Kreiner
T
T
Scheller
R H
RH
D018171:Agrin; D000818:Animals; D015153:Blotting, Western; D002450:Cell Communication; D002460:Cell Line; D015723:Gene Library; D008970:Molecular Weight; D009132:Muscles / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D051381:Rats; D011950:Receptors, Cholinergic / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification; D013116:Spinal Cord / Q000502:physiology*; D013569:Synapses / Q000502:physiology* / Q000648:ultrastructure; D013570:Synaptic Membranes / Q000502:physiology; D014162:Transfection
D018171:Agrin; D009419:Nerve Tissue Proteins; D011950:Receptors, Cholinergic; D011993:Recombinant Fusion Proteins