title: Genetical and cytological location of the structural parts coding for the first three steps of pyrimidine biosynthesis in Drosophila melanogaster.
abstract: The rudimentary locus (r; X--55.3) of Drosophila melanogaster is shown to contain the structural sequences for the enzymes CPSase, ATCase and DHOase. The enzyme concentration in adult flies is correlated with the number of r+ copies in the genome. The expression of the locus follows the rules of the gene dosage compensation hypothesis when extracts of newly emerged males and females are compared.
mesh_terms: D000818:Animals; D001221:Aspartate Carbamoyltransferase / Q000235:genetics; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing) / Q000235:genetics; D002874:Chromosome Mapping; D004080:Dihydroorotase / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D005796:Genes; D008297:Male; D011743:Pyrimidines / Q000096:biosynthesis*; D014960:X Chromosome
chemical_list: D011743:Pyrimidines; D001221:Aspartate Carbamoyltransferase; D004080:Dihydroorotase; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)