Binding of PH domains of beta-adrenergic receptor kinase and beta-spectrin to WD40/beta-transducin repeat containing regions of the beta-subunit of trimeric G-proteins

Biochem Biophys Res Commun. 1994 Aug 30;203(1):29-35. doi: 10.1006/bbrc.1994.2144.


Pleckstrin homology (PH) domains are found in numerous proteins important in signal transduction and cytoskeletal function. Several PH domains are now known to contain a binding site for the beta gamma subunits of trimeric G-proteins (G beta gamma), a finding which naturally raises the question of where on the G beta gamma complex these PH domains bind. Here we demonstrate binding of the PH domains of beta-adrenergic receptor kinase and beta-spectrin to the G beta subunit and not the G gamma subunit in a nitrocellulose gel replica assay. Furthermore, the C-terminal tryptic fragment of G beta containing only 5 WD40/beta-transducin (WD40) repeats also binds these two PH domains. Finally, constructs containing only WD40 repeats of G beta were shown to bind to beta-ARK and beta-spectrin PH domains in solution. These findings suggest that WD40 repeats of G beta are ligands for PH domains and have interesting implications for other proteins containing WD40 sequences.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Brain / metabolism
  • Cattle
  • Chromatography, DEAE-Cellulose
  • Cyclic AMP-Dependent Protein Kinases / chemistry*
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • Female
  • GTP-Binding Proteins / chemistry*
  • GTP-Binding Proteins / isolation & purification
  • Macromolecular Substances
  • Molecular Sequence Data
  • Rats
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism
  • Spectrin / chemistry*
  • Spectrin / metabolism*
  • Transducin / metabolism*
  • beta-Adrenergic Receptor Kinases


  • Macromolecular Substances
  • Recombinant Fusion Proteins
  • Spectrin
  • Cyclic AMP-Dependent Protein Kinases
  • beta-Adrenergic Receptor Kinases
  • GTP-Binding Proteins
  • Transducin

Associated data

  • GENBANK/M87854