Open AccessEffect of insect hormones on RNA polymerases of mass-isolated imaginal discs of Drosophila melanogaster cultured in vitro.
Author(s) -
James T. Nishiura,
James W. Fristrom
Publication year - 1975
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.72.8.2984
Subject(s) - ecdysone , biology , drosophila melanogaster , rna , rna polymerase , polymerase , incubation , microbiology and biotechnology , cycloheximide , biochemistry , rna polymerase i , imaginal disc , rna polymerase ii , in vitro , hormone , dna , gene expression , protein biosynthesis , gene , promoter
Four chromatographically separable DNA-dependent RNA polymerases (nucleosidetriphosphate:RNA nucleotidyltransferase; EC 2.7.7.6) were partially purified from imaginal discs of Drosophila melanogaster. Their properties are similar to those described for RNA polymerases I and II isolated from other eukaryotes. In vitro incubation of discs with beta-ecdysone, juvenile hormone, or cycloheximide resulted in increased activity of RNA polymerase I. The increase was irreversible with beta-ecdysone incubation and removal but reversible with juvenile hormone incubation and removal. With beta-ecdysone, the rate of the increase in polymerase I activity paralleled the kinetics of ecdysone binding to discs and increases in the rate of precursor incorporation into RNA. A model to explain the increased acticity of RNA polymerase I is presented.