Transcriptional repression by COUP-TF II is dependent on the C-terminal domain and involves the N-CoR variant, RIP13delta1

J Steroid Biochem Mol Biol. Nov-Dec 1997;63(4-6):165-74. doi: 10.1016/s0960-0760(97)00079-4.

Abstract

COUP-TF II/ARP-1 is an 'orphan' steroid receptor that inhibits basal transcription, and represses trans-activation by the vitamin D, thyroid hormone and retinoid receptors. The molecular basis of repression by COUP-TF II remains obscure. In this study we utilized the GAL4 hybrid system to demonstrate that COUP-TF II contains sequences within the C-terminal region that encode a dominant transcriptional repressor that inhibits the ability of the potent chimeric transactivator GAL4VP16 to induce transcription. Mammalian two hybrid analysis demonstrated that COUP-TF II did not efficiently interact with either interaction domains I or II from N-CoR and RIP13. However, COUP-TF II efficiently interacts with a region comprised of interaction domains I + II from the corepressor, RIP13delta1. Efficient interaction of the orphan receptor with the corepressor was critically dependent on a large region comprised of the C, D and E domains of COUP-TF II, which correlated with the domain that maximally represses transcription. This investigation suggested that the N-CoR variant, RIP13delta1 interacts with a region of COUP-TF II that functions as a dominant transcriptional repressor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Bromo Cyclic Adenosine Monophosphate / pharmacology
  • Animals
  • COS Cells
  • COUP Transcription Factors
  • Chloramphenicol O-Acetyltransferase / genetics
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / metabolism*
  • Fungal Proteins / metabolism
  • Gene Expression Regulation
  • Humans
  • Okadaic Acid / pharmacology
  • Receptors, Steroid*
  • Trans-Activators / metabolism
  • Transcription Factors / chemistry
  • Transcription Factors / metabolism*
  • Transcription, Genetic* / drug effects
  • Tumor Cells, Cultured

Substances

  • COUP Transcription Factors
  • DNA-Binding Proteins
  • Fungal Proteins
  • Gal-VP16
  • Receptors, Steroid
  • Trans-Activators
  • Transcription Factors
  • Okadaic Acid
  • 8-Bromo Cyclic Adenosine Monophosphate
  • Chloramphenicol O-Acetyltransferase