Phosducin-like protein (PhLP), a regulator of G beta gamma function, interacts with the proteasomal protein SUG1

Biochim Biophys Acta. 1998 Mar 12;1402(1):95-101. doi: 10.1016/s0167-4889(97)00141-9.

Abstract

Phosducin-like protein (PhLP) and phosducin are highly homologous proteins that interact with the beta gamma subunits of guanine nucleotide binding proteins. While phosducin has a well-characterized role in retinal signal transduction, PhLP function remains unclear. To further understand the function of PhLP, we have examined other potential protein:protein interactions with PhLP using the yeast two-hybrid system. PhLP was found to interact with a mouse homologue of the yeast SUG1, a subunit of the 26S proteasome which may also indirectly modulate transcription. This interaction was further confirmed by an in vitro binding assay and co-immunoprecipitation of the two proteins in overexpression studies. Inhibition of proteasome function by lactacystin led to accumulation of high molecular weight, ubiquitin-immunoreactive protein precipitated by PhLP antiserum. We suggest that PhLP/SUG1 interaction may target PhLP for proteasomal degradation.

Publication types

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

MeSH terms

  • Adenosine Triphosphatases
  • Animals
  • Blotting, Western
  • COS Cells
  • Carrier Proteins / analysis
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Cloning, Organism
  • Fungal Proteins / chemistry
  • Fungal Proteins / metabolism*
  • GTP-Binding Proteins / antagonists & inhibitors
  • GTP-Binding Proteins / metabolism*
  • Glioma
  • Glutathione Transferase
  • Hybrid Cells
  • Mice
  • Molecular Chaperones
  • Nerve Tissue Proteins / analysis
  • Nerve Tissue Proteins / chemistry
  • Nerve Tissue Proteins / metabolism*
  • Neuroblastoma
  • Peptide Hydrolases / chemistry
  • Peptide Hydrolases / isolation & purification
  • Peptide Hydrolases / metabolism*
  • Proteasome Endopeptidase Complex*
  • Rats
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / isolation & purification
  • Recombinant Fusion Proteins / metabolism
  • Repressor Proteins / chemistry
  • Repressor Proteins / metabolism*
  • Saccharomyces cerevisiae
  • Saccharomyces cerevisiae Proteins*
  • Signal Transduction
  • Transcription, Genetic
  • Transfection

Substances

  • Carrier Proteins
  • Fungal Proteins
  • Molecular Chaperones
  • Nerve Tissue Proteins
  • Pdcl protein, mouse
  • Pdcl protein, rat
  • Recombinant Fusion Proteins
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins
  • Glutathione Transferase
  • Peptide Hydrolases
  • Proteasome Endopeptidase Complex
  • ATP dependent 26S protease
  • Adenosine Triphosphatases
  • GTP-Binding Proteins
  • RPT6 protein, S cerevisiae