Directing Traffic at the Neuromuscular Junction

Motor nerves activate muscles via the release of acetylcholine, a neurotransmitter that binds to muscle cells’ acetylcholine receptors. The occupied receptors then allow Na+ ions into the muscle cells, depolarizing them and causing them to contract. This transmission of signals across the neuromuscular junction is most efficient when the receptors are positioned close to the sites of acetylcholine release, so it is not surprising that the receptors form clusters at these locations. But how do they ‘know’ where to congregate? A recent study of the nematode Caenorhabditis elegans by Christelle Gally and colleagues shows that a protein known as LEV-10 enables acetylcholine receptors to cluster properly, at least in this particular organism.