Allosteric regulation of even-skipped repression activity by phosphorylation

Mol Cell. 1999 Jan;3(1):77-86. doi: 10.1016/s1097-2765(00)80176-8.

Abstract

The Drosophila homeodomain protein Even-skipped (Eve) is a well characterized transcriptional repressor. Here, we show that Eve's ability to function in vitro is negatively regulated by phosphorylation. DNA-binding activity was unaffected by phosphorylation, but phosphorylated Eve was unable to interact with the TATA-binding protein (TBP), a known target for repression. Unexpectedly, phosphorylation of the Eve N terminus, which is dispensable for repression and TBP binding, was necessary and sufficient to inactivate Eve. LiCl, which specifically inhibits glycogen synthase kinase-3 (GSK-3), reduced Eve phosphorylation in nuclear extract and blocked inhibition of repression. In addition, Eve was phosphorylated and inactivated by purified GSK-3 beta plus casein kinase II. Our results suggest a novel mechanism of transcriptional control involving phosphorylation-induced allosteric interference with a repressive protein-protein interaction.

Publication types

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

MeSH terms

  • Allosteric Regulation / genetics
  • Animals
  • Bacterial Proteins*
  • Calcium-Calmodulin-Dependent Protein Kinases / metabolism
  • Casein Kinase II
  • DNA-Binding Proteins / metabolism
  • Drosophila / genetics*
  • Drosophila Proteins*
  • Glycogen Synthase Kinase 3
  • Glycogen Synthase Kinases
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / metabolism
  • Lithium / pharmacology
  • Phosphorylation
  • Protein Serine-Threonine Kinases / metabolism
  • Repressor Proteins / genetics*
  • TATA-Box Binding Protein
  • Trans-Activators / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • Bacterial Proteins
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Homeodomain Proteins
  • Repressor Proteins
  • TATA-Box Binding Protein
  • Trans-Activators
  • Transcription Factors
  • bcd protein, Drosophila
  • eve protein, Drosophila
  • Lithium
  • Glycogen Synthase Kinases
  • Casein Kinase II
  • Protein Serine-Threonine Kinases
  • Sgg protein, Drosophila
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Glycogen Synthase Kinase 3