Tetraspanins in flies

The tetraspanins form a large family of four-transmembrane-spanning proteins that are involved in a wide range of cellular functions in mammals. In the October 15 Proceedings of the National Academy of Sciences Fradkin et al describe characterization of tetraspanin expression and functions in Drosophila (Proc Natl Acad Sci USA, 99:13663-13668, October 15, 2002).

The first tetraspanin gene to be identified in flies was Latebloomer (lbm), which is expressed in motoneurons and has been implicated in the formation of synaptic contacts at the neuromuscular junction. Analysis of the Drosophila melanogaster genome sequence revealed the existence of 34 other genes encoding tetraspanins.

Fradkin et al performed RNA in situ hybridization analysis of tetraspanin expression during Drosophila development. The genes show very different expression patterns, but fall into three groups that are expressed in the nervous system, the gut or the epidermis. In addition to lbm, two...