Nitric oxide synthase (NOS-1) coclustered with agrin-induced AChR-specializations on cultured skeletal myotubes

Mol Cell Neurosci. 2000 Sep;16(3):269-81. doi: 10.1006/mcne.2000.0873.


Previously we reported that neuronal nitric oxide synthase type-1 (NOS-1) is expressed in skeletal myotubes in vitro. In the present paper we sought to determine whether agrin-induced membrane specializations known to include the nicotinic acetylcholine receptor (AChR) on cultured myotubes may also contain NOS-1 and related molecules. After treatment with various agrin constructs containing the full C-terminally AChR-clustering domain (fragments N2, N4), but not with fragment C2 (truncated), NOS-1 expressed in the cytosol of mouse C2C12 skeletal myotubes coclustered with AChR, 43K rapsyn, MuSK, and the dystrophin/utrophin glycoprotein-complex (DUGC). Agrin-induced specializations also included coaggregates of N-methyl-d-aspartic acid (NMDA)-receptor, alpha-sodium (NaCh), or Shaker-type K+ channel (KCh)/PSD-95 complexes, and NOS-1. We conclude that agrin is crucial for recruitment of preassembled multimolecular membrane clusters, including AChR, NMDAR, and ion channels linked to NOS-1. Coassembly of NOS-1 to postsynaptic molecules may reflect site-specific NO-signaling pathways in neuromuscular junction formation and functions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agrin / pharmacology*
  • Animals
  • Cell Line
  • Ion Channels / metabolism
  • Mice
  • Muscle Proteins / metabolism
  • Muscle, Skeletal / metabolism*
  • Nerve Tissue Proteins / metabolism
  • Nitric Oxide Synthase / metabolism*
  • Nitric Oxide Synthase Type I
  • Receptor Aggregation
  • Receptor Protein-Tyrosine Kinases / metabolism
  • Receptors, Cholinergic / drug effects*
  • Receptors, Cholinergic / metabolism*


  • Agrin
  • Ion Channels
  • Muscle Proteins
  • Nerve Tissue Proteins
  • Receptors, Cholinergic
  • peripheral membrane protein 43K
  • postsynaptic density proteins
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type I
  • Nos1 protein, mouse
  • Receptor Protein-Tyrosine Kinases