Identification of a novel partner of RNA polymerase II subunit 11, Che-1, which interacts with and affects the growth suppression function of Rb

FASEB J. 2000 May;14(7):904-12. doi: 10.1096/fasebj.14.7.904.

Abstract

hRPB11 is a core subunit of RNA polymerase II (pol II) specifically down-regulated on doxorubicin (dox) treatment. Levels of this protein profoundly affect cell differentiation, cell proliferation, and tumorigenicity in vivo. Here we describe Che-1, a novel human protein that interacts with hRPB11. Che-1 possesses a domain of high homology with Escherichia coli RNA polymerase final sigma-factor 70 and SV40 large T antigen. In addition, we report that Che-1 interacts with the retinoblastoma susceptibility gene (Rb) by two distinct domains. Functionally, we demonstrate that Che-1 represses the growth suppression function of Rb, counteracting the inhibitory action of Rb on the trans-activation function of E2F1. These results identify a novel protein that binds Rb and the core of pol II, and suggest that Che-1 may be part of transcription regulatory complex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Carrier Proteins*
  • Cell Cycle / physiology
  • Cell Cycle Proteins*
  • Cell Division / physiology
  • Cell Line
  • Cloning, Molecular
  • DNA-Binding Proteins*
  • E2F Transcription Factors
  • E2F1 Transcription Factor
  • Humans
  • Molecular Sequence Data
  • Protein Binding
  • RNA Polymerase II / chemistry
  • RNA Polymerase II / metabolism*
  • Retinoblastoma Protein / antagonists & inhibitors
  • Retinoblastoma Protein / metabolism*
  • Retinoblastoma Protein / physiology
  • Retinoblastoma-Binding Protein 1
  • Sequence Homology, Amino Acid
  • Transcription Factor DP1
  • Transcription Factors / metabolism

Substances

  • Carrier Proteins
  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • E2F Transcription Factors
  • E2F1 Transcription Factor
  • E2F1 protein, human
  • Retinoblastoma Protein
  • Retinoblastoma-Binding Protein 1
  • Transcription Factor DP1
  • Transcription Factors
  • RNA Polymerase II