Temperature-sensitive prune (pn) mutations of Drosophila melanogaster

Abstract

Temperature-sensitivemutations, at the prune locus ( pn ts) of Drosophila melanogaster, were induced with EMS. The majority of the new class of mutations, designated pn ts-e, do not interact with the mutation Killer of prune (Kpn) at all of the experimental temperatures, i.e., pn ts-e; Kpn flies do not die. One mutation, designated pn ts-ek, is temperature-sensitive with respect to both the eye coloration and the interaction with Kpn. pn tr (temperature-non-sensitive), pn ts-e, and pn ts-ek alleles were found to differ with respect to both quantity of drosopterines and the color of the eyes. The temperature-sensitive period (TSP) for pn eye color occurs at a late pupal stage. The TSP for the pn—Kpn interaction lasts from the beginning of the first laraval instar to eclosion [22]. It is concluded that all pn mutations known to date occupy the same functional unit. The various pn mutations affect the same metabolic step to various degrees: the eye color phenotype results from a reduction in the end product, while the interaction with Kpn depends on the amount of the accumulated precursor. No recombination between pn alleles was found among more than 10 6 zygotes that were scored. The reasons for this failure are disscussed.