A DISTINCT POTASSIUM CHANNEL POLYPEPTIDE ENCODED BY THE DROSOPHILA-EAG LOCUS

Many of the signaling properties of neurons and other electrically excitable cells are determined by a diverse family of potassium channels. A number of genes that encode potassium channel polypeptides have been cloned from various organisms on the basis of their sequence similarity to the Drosophila Shaker (Sh) locus. As an alternative strategy, a molecular analysis of other Drosophila genes that were defined by mutations that perturb potassium channel function was undertaken. Sequence analysis of complementary DNA from the ether a go-go (eag) locus revealed that it encodes a structural component of potassium channels that is related to but is distinct from all identified potassium channel polypeptides.