Agonist-induced membrane nanodomain clustering drives GLP-1 receptor responses in pancreatic beta cells

PLoS Biol. 2019 Aug 20;17(8):e3000097. doi: 10.1371/journal.pbio.3000097. eCollection 2019 Aug.

Abstract

The glucagon-like peptide-1 receptor (GLP-1R), a key pharmacological target in type 2 diabetes (T2D) and obesity, undergoes rapid endocytosis after stimulation by endogenous and therapeutic agonists. We have previously highlighted the relevance of this process in fine-tuning GLP-1R responses in pancreatic beta cells to control insulin secretion. In the present study, we demonstrate an important role for the translocation of active GLP-1Rs into liquid-ordered plasma membrane nanodomains, which act as hotspots for optimal coordination of intracellular signaling and clathrin-mediated endocytosis. This process is dynamically regulated by agonist binding through palmitoylation of the GLP-1R at its carboxyl-terminal tail. Biased GLP-1R agonists and small molecule allosteric modulation both influence GLP-1R palmitoylation, clustering, nanodomain signaling, and internalization. Downstream effects on insulin secretion from pancreatic beta cells indicate that these processes are relevant to GLP-1R physiological actions and might be therapeutically targetable.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Cell Membrane / metabolism
  • Cluster Analysis
  • Cricetulus
  • Cyclic AMP / metabolism
  • Diabetes Mellitus, Type 2
  • Endocytosis / drug effects
  • Glucagon-Like Peptide 1 / agonists
  • Glucagon-Like Peptide 1 / metabolism
  • Glucagon-Like Peptide-1 Receptor / metabolism*
  • Glucagon-Like Peptide-1 Receptor / physiology
  • HEK293 Cells
  • Humans
  • Insulin / metabolism
  • Insulin Secretion / physiology
  • Insulin-Secreting Cells / metabolism*
  • Insulin-Secreting Cells / physiology
  • Lipoylation
  • Signal Transduction / drug effects

Substances

  • Glucagon-Like Peptide-1 Receptor
  • Insulin
  • Glucagon-Like Peptide 1
  • Cyclic AMP

Associated data

  • figshare/10.6084/m9.figshare.c.4592000