Regulation of G-protein coupled receptor traffic by an evolutionary conserved hydrophobic signal

Tim Angelotti, David Daunt, Olga G. Shcherbakova, Brian Kobilka, Carl M. Hurt

Research output: Contribution to journalArticleResearchpeer-review

27 Citations (Scopus)


Plasma membrane (PM) expression of G-protein coupled receptors (GPCRs) is required for activation by extracellular ligands; however, mechanisms that regulate PM expression of GPCRs are poorly understood. For some GPCRs, such as alpha2c-adrenergic receptors (α2c-ARs), heterologous expression in non-native cells results in limited PM expression and extensive endoplasmic reticulum (ER) retention. Recently, ER export/retentions signals have been proposed to regulate cellular trafficking of several GPCRs. By utilizing a chimeric α2a2c-AR strategy, we identified an evolutionary conserved hydrophobic sequence (ALAAALAAAAA) in the extracellular amino terminal region that is responsible in part for α2c-AR subtype-specific trafficking. To our knowledge, this is the first luminal ER retention signal reported for a GPCR. Removal or disruption of the ER retention signal dramatically increased PM expression and decreased ER retention. Conversely, transplantation of this hydrophobic sequence into α2a-ARs reduced their PM expression and increased ER retention. This evolutionary conserved hydrophobic trafficking signal within α2c-ARs serves as a regulator of GPCR trafficking.

Original languageEnglish
Pages (from-to)560-578
Number of pages19
Issue number4
Publication statusPublished - Apr 2010
Externally publishedYes


  • ER export
  • ER retention
  • GPCR trafficking
  • Protein sorting
  • Retention signal

Cite this