Gust J, a salt-insensitive mutant ofDrosophila melanogaster

Abstract

A set of 340 P insert lines on the X chromosome and the autosomes were screened for altered responses of the labellar chemoreceptors to salts and sucrose. A mutant linegustJ was isolated in which the electrophysiological response of the salt-sensitive neuron to Na+ in the sensilla of the proboscis is reduced. The responses to KC1 and sucrose are unaffected. In feeding tests,gustJ flies have Na+-specific defects. Heterozygotes ofgustJ with two other salt mutantsgustE andBE1323 are normal. Multiple alleles ofgustJ have been obtained by excision of the original P element. All mutants have defects in Na+ sensing specifically, thus defining a new gene that affects Na+ response of the fly.