Nerve-muscle interactions in the embryo.

Nerve and muscle develop in the embryo through a process of continuous interaction. Some of these interactions have been known in simple fashion for some time, for example, that full development of muscle requires the presence of innervating nerves and vice versa. However, the mechanisms by which the interactions proceed are still largely unknown and current re-examination of nerve-muscle interactions in the embryo are providing interesting insights into, among other things, the development of fast and slow muscle fibres and mutual recognition by muscles and nerves.