Invitation Paper: Behavior Indrosophila Melanogastera Geneticist's View

In screening Drosophila melanogaster for mutations which cause paralysis at 29 c C and recovery of mobility at 22 c C, 11 temperature-sensitive (ts) mutants were detected among 1.35 × 10 6 flies screened. These mutations fell into 3 loci, paralytic (para ts ), shibire (shi ts ) and stoned (stn ts ). All three loci affect neurological development. The best explanation for para ts appears to be an effect on the inhibitory neuronal system. The shi alleles affect an array of developmental events from early embryos to adults. The pattern of heat-induced changes in shi ts1 electroretinograms (ERG) is consistent with a ts membranal defect. This is supported by a ts resistance of shi ts flies to tetrodotoxin which specifically blocks the sodium channel of nerves.The final locus, stn, causes sensitivity to the trauma of temperature changes. A jump response observed when a light is turned off is related to a large "offtransient" in ERGs which is correlated with a simultaneous muscle spike. The property of temperature-sensitivity allows greater analytic powers in the study of neurological mutants.