GPCR Signaling and Trafficking: The Long and Short of It

Trends Endocrinol Metab. 2017 Mar;28(3):213-226. doi: 10.1016/j.tem.2016.10.007. Epub 2016 Nov 23.


Emerging findings disclose unexpected components of G protein-coupled receptor (GPCR) signaling and cell biology. Select GPCRs exhibit classical signaling, that is restricted to cell membranes, as well as newly described persistent signaling that depends on internalization of the GPCR bound to β-arrestins. Termination of non-canonical endosomal signaling requires intraluminal acidification and sophisticated protein trafficking machineries. Recent studies reveal the structural determinants of the trafficking chaperones. This review summarizes advances in GPCR signaling and trafficking with a focus on the parathyroid hormone receptor (PTHR) as a prototype, and on the actin-sorting nexin 27 (SNX27)-retromer tubule (ASRT) complex, an endosomal sorting hub responsible for recycling and preservation of cell surface receptors. The findings are integrated into a model of PTHR trafficking with implications for signal transduction, bone growth, and mineral ion metabolism.

Keywords: ASRT complex; GPCR; PTHR; SNX27; endosome; retromer.

Publication types

  • Review
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Endosomes / genetics
  • Endosomes / metabolism*
  • Humans
  • Protein Transport / genetics
  • Protein Transport / physiology
  • Receptor, Parathyroid Hormone, Type 1 / genetics
  • Receptor, Parathyroid Hormone, Type 1 / metabolism
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism*
  • Signal Transduction / genetics
  • Signal Transduction / physiology
  • Sorting Nexins / genetics
  • Sorting Nexins / metabolism


  • Receptor, Parathyroid Hormone, Type 1
  • Receptors, G-Protein-Coupled
  • Sorting Nexins