The human retinoblastoma susceptibility gene promoter is positively autoregulated by its own product

J Biol Chem. 1994 Feb 25;269(8):6083-8.

Abstract

The product of the retinoblastoma susceptibility gene is a 105-kDa protein that has properties of a cell cycle regulatory factor. Previous reports indicated that two distinct DNA-binding factors, RBF-1 and ATF, play an important part in the transcription of the human retinoblastoma gene (Rb). Recently, we demonstrated that pRb activates expression of the human transforming growth factor-beta 2 gene through ATF-2. Since the human Rb gene promoter also contains an ATF-2-like binding site, we examined whether pRb can regulate its own expression through ATF-2. Here we report that overexpression of Rb stimulates Rb promoter activity through the ATF binding site in a variety of different cell types. Mutation of the ATF binding site of the Rb promoter abolishes the Rb autoinduction. We have also determined that the carboxyl-terminal domain of pRb is responsible for the Rb autoinduction through ATF-2. Rb autoinduction may be important for maintaining the action of pRb during cell growth, and loss of autoinductibility may contribute to retinoblastoma.

Publication types

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

MeSH terms

  • Activating Transcription Factors
  • Animals
  • Base Sequence
  • Binding Sites
  • Blood Proteins / metabolism
  • Cell Line
  • DNA
  • Gene Expression Regulation*
  • Genes, Retinoblastoma*
  • Humans
  • Mink
  • Molecular Sequence Data
  • Neoplasm Proteins / metabolism
  • Promoter Regions, Genetic*
  • Retinoblastoma Protein / genetics*
  • Retinoblastoma Protein / metabolism
  • Transcription Factors / metabolism
  • Transcription, Genetic
  • Tumor Cells, Cultured

Substances

  • Activating Transcription Factors
  • Blood Proteins
  • Neoplasm Proteins
  • Retinoblastoma Protein
  • Transcription Factors
  • DNA