Acetylcholinesterase - new roles for an old actor

The discovery of the first neurotransmitter acetylcholine - was soon follow ed by the discovery of its hydrolysing enzyme, acetylcholinesterase. The ro le of acetylcholinesterase in terminating acetylcholine-mediated neurotrans mission made it the focus of intense research for much of the past century. But the complexity of acetylcholinesterase gene regulation and recent evid ence for some of the long-suspected 'non-classical' actions of this enzyme have more recently driven a profound revolution in acetylcholinesterase res earch. Although our understanding of the additional roles of acetylcholines terase is incomplete, the time is ripe to summarize the evidence on a remar kable diversity of acetylcholinesterase functions.