Cosuppression in Drosophila: gene silencing of Alcohol dehydrogenase by white-Adh transgenes is Polycomb dependent

Cell. 1997 Aug 8;90(3):479-90. doi: 10.1016/s0092-8674(00)80508-5.


When two to six copies of a white promoter-Alcohol dehydrogenase (Adh) reporter fusion gene are introduced into the genome, the expression is progressively reduced both in larvae and adults rather than the expected gene dosage effect. In addition, multiple transgenes reduce endogenous Adh transcripts, a result that is strongly analogous to "cosuppression" phenomena described in many plant species but which has not been previously observed in animals. Silencing of the Adh gene is not influenced by zeste-dependent transvection but strongly affected by the Polycomb and Polycomblike mutations. Polycomb and polyhomeotic proteins are bound to the chromatin at the sites of the repressed w-Adh transgenes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alcohol Dehydrogenase / biosynthesis*
  • Animals
  • Animals, Genetically Modified
  • Chromatin / physiology
  • Chromosome Mapping
  • Crosses, Genetic
  • DNA-Binding Proteins / metabolism
  • Drosophila Proteins
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / physiology
  • Female
  • Gene Expression Regulation, Developmental*
  • Genes, Insect
  • Genes, Reporter
  • Larva
  • Male
  • Mutagenesis, Insertional
  • Plasmids
  • Promoter Regions, Genetic
  • Recombinant Fusion Proteins / biosynthesis
  • Suppression, Genetic*
  • Transcription, Genetic
  • Transfection


  • Chromatin
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Recombinant Fusion Proteins
  • z protein, Drosophila
  • Alcohol Dehydrogenase