Identification of the Gbeta5-RGS7 protein complex in the retina

Biochem Biophys Res Commun. 1998 Aug 28;249(3):898-902. doi: 10.1006/bbrc.1998.9218.


The G protein beta subunit G beta 5 deviates significantly from the four other members of the G beta family in amino acid sequence, unique expression pattern (only in the CNS), and cytosolic localization. To identify the members of the G beta 5-mediated signaling pathway, we purified the native protein complex containing G beta 5 from the cytosolic fraction of bovine retina. Analysis of the isolated complex revealed that G beta 5 is tightly associated with RGS7, a member of the superfamily of negative regulators of G protein signaling. This finding, for the first time, demonstrates an interaction between a G beta subunit and an RGS protein. G beta 5 was not detected in the outer segments of photoreceptor cells, suggesting that the cytosolic G beta 5-RGS7 complex is not directly involved in phototransduction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cattle
  • Cytosol / chemistry
  • Cytosol / metabolism
  • Eye Proteins / chemistry
  • Eye Proteins / isolation & purification*
  • GTP-Binding Protein beta Subunits*
  • GTP-Binding Proteins / chemistry
  • GTP-Binding Proteins / isolation & purification*
  • Heterotrimeric GTP-Binding Proteins*
  • In Vitro Techniques
  • Macromolecular Substances
  • Peptide Fragments / chemistry
  • Peptide Fragments / isolation & purification
  • Retina / chemistry*
  • Rod Cell Outer Segment / chemistry
  • Vision, Ocular


  • Eye Proteins
  • GTP-Binding Protein beta Subunits
  • Macromolecular Substances
  • Peptide Fragments
  • GTP-Binding Proteins
  • Heterotrimeric GTP-Binding Proteins