A 100 amino acid region in the GABA rho 1 subunit confers robust homo-oligomeric expression

Neuroreport. 1997 Apr 14;8(6):1425-30. doi: 10.1097/00001756-199704140-00020.

Abstract

Retinal gamma-aminobutyric acid type C (GABAC) receptors are believed to be composed of rho subunits. Although rho 1 and rho 2 are over 80% similar, the whole-cell currents generated by rho 1 receptors in Xenopus oocytes are significantly greater than those generated by rho 2 receptors. In this study, chimeric subunits containing different portions of human rho 1 and human rho 2 were created to localize sequences facilitating robust rho 1 expression. Our results indicate that these sequences reside in a 100 amino acid domain in the N-terminus of rho 1, and may involve N-linked glycosylation. Since the N-terminus also contains subunit assembly signals, rho 1 receptors may be formed more efficiently than rho 2 receptors. Therefore, this study furthers our understanding of the molecular basis of GABA-mediated inhibition in the retina.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Biopolymers
  • Glycosylation
  • Humans
  • Molecular Sequence Data
  • Patch-Clamp Techniques
  • Peptide Fragments / chemistry*
  • Protein Structure, Tertiary*
  • Receptors, GABA / chemistry*
  • Recombinant Fusion Proteins / chemistry*
  • Xenopus

Substances

  • Biopolymers
  • Peptide Fragments
  • Receptors, GABA
  • Recombinant Fusion Proteins