Pancreatic alpha cells modulate beta cell function in a paracrine manner through the release of glucagon. However, the detailed molecular architecture underlying alpha-to-beta cell regulation remains Show more
Pancreatic alpha cells modulate beta cell function in a paracrine manner through the release of glucagon. However, the detailed molecular architecture underlying alpha-to-beta cell regulation remains poorly characterized. Here, we show that the glucagon-like peptide-1 receptor (GLP1R) is enriched as nanodomains on beta cell membranes that contact alpha cells, in keeping with increased single-molecule transcript expression. At low glucose, beta cells next to alpha cells directly sense micromolar glucagon release by pre-internalizing GLP1R. Pre-internalized GLP1R is associated with earlier beta cell Ca Show less