4 ACETYLCHOLINESTERASE GENES IN THE NEMATODE CAENORHABDITIS-ELEGANS

Whereas a single gene encodes acetylcholinesterase (AChE) in vertebrat es and most insect species, four distinct genes have been cloned and c haracterized in the nematode Caenorhabditis elegans. We found that ace -1 (mapped to chromosome X) is prominently expressed in muscle cells w hereas ace-2 (located on chromosome I) is mainly expressed in neurons. Ace-x and ace-y genes are located in close proximity on chromosome II where they are separated by only a few hundred base pairs. The role o f these two genes is still unknown. ((C) Elsevier, Paris).