Isolation and characterization of deficiencies exposing therudimentarylocus ofDrosophila melanogaster

Abstract

SUMMARYTherudimentarylocus ofDrosophila melanogastercontains the structural information for the first three enzymes of thede novopyrimidine pathway. Two newrudimentary (r)mutants have been isolated following mutagenesis with ICR-170. From complementation analysis and cyto-genetical observation both were shown to be deficiencies which expose therlocus.Df(1)r19is deleted from band 14D1 to 15D1 andDf(1)r1Dfrom band 14B6 to 15A2. These deficiencies were combined with several characterizedralleles each giving a single enzymatic defect in one of the first three enzymes of the pyrimidine pathway. An unusual semilethaltranseffect was observed in some but not all the combinations. The effect was not observed with a third smaller deficiency which also exposes therudimentarylocus.