A pp32-retinoblastoma protein complex modulates androgen receptor-mediated transcription and associates with components of the splicing machinery

Biochem Biophys Res Commun. 2005 Aug 26;334(2):702-8. doi: 10.1016/j.bbrc.2005.06.153.


We have previously shown pp32 and the retinoblastoma protein interact. pp32 and the retinoblastoma protein are nuclear receptor transcriptional coregulators: the retinoblastoma protein is a coactivator for androgen receptor, the major regulator of prostate cancer growth, while pp32, which is highly expressed in prostate cancer, is a corepressor of the estrogen receptor. We now show pp32 increases androgen receptor-mediated transcription and the retinoblastoma protein modulates this activity. Using affinity purification and mass spectrometry, we identify members of the pp32-retinoblastoma protein complex as PSF and nonO/p54nrb, proteins implicated in coordinate regulation of nuclear receptor-mediated transcription and splicing. We show that the pp32-retinoblastoma protein complex is modulated during TPA-induced K562 differentiation. Present evidence suggests that nuclear receptors assemble multiprotein complexes to coordinately regulate transcription and mRNA processing. Our results suggest that pp32 and the retinoblastoma protein may be part of a multiprotein complex that coordinately regulates nuclear receptor-mediated transcription and mRNA processing.

Publication types

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

MeSH terms

  • Cell Differentiation / drug effects
  • Cell Differentiation / physiology
  • Gene Expression Regulation / drug effects
  • Gene Expression Regulation / physiology
  • Humans
  • K562 Cells
  • Multiprotein Complexes / metabolism
  • Nuclear Proteins / metabolism*
  • Phosphoproteins / metabolism
  • Protein Splicing / drug effects
  • Protein Splicing / physiology*
  • Receptors, Androgen / metabolism*
  • Retinoblastoma Protein / metabolism*
  • Tetradecanoylphorbol Acetate / pharmacology
  • Transcriptional Activation / drug effects
  • Transcriptional Activation / physiology*


  • Multiprotein Complexes
  • Nuclear Proteins
  • Phosphoproteins
  • Receptors, Androgen
  • Retinoblastoma Protein
  • Tetradecanoylphorbol Acetate