Neuregulin potentiates agrin-induced acetylcholine receptor clustering in myotubes

Abstract

Agrin and neuregulin (HRG-β1) play complementary roles in synapse formation. While HRG-β1 induces transcriptional up-regulation of postsynaptic proteins, here we present evidence that it can potentiate agrin-induced acetylcholine receptor (AChR) clustering in C2 myotubes. Agrin induced maximal AChR clustering in 4 h. HRG-β1 treatment for 4 h produced no increase over basal AChR cluster numbers. When myotubes were treated for 4 h with 100 pM agrin, HRG-β1 augmented AChR cluster numbers by 2-fold compared to myotubes treated with 100 pM agrin alone. Thus, HRG-β1 can potentiate agrin-induced AChR clustering.