Pancreatic beta-cell receptors and G proteins coupled to adenylyl cyclase.
Glucagon and tGLP-1 receptors can be either coexpressed or selectively expressed in beta-cell models. Our results indicate that both these peptides can regulate insulin secretion from beta-cells through their own specific receptors. The finding of a selective expression of G proteins in insulin and glucagon cells indicates a clear difference in their transduction pathways. A key role of the G alpha s family in beta-cell function is further supported by its conserved cell distribution between different species. In conclusion, one could postulate that in the human beta-cells, tGLP-1 and glucagon receptors could mediate their action through different G protein alpha-subunits of the G alpha s family.
Marie
J C
JC
Institut National de la Santé et de la Recherche Médicale, INSERM Unité 55, Hôpital Saint-Antoine, Paris, France.
Rosselin
G
G
Skoglund
G
G
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D019204:GTP-Binding Proteins / Q000378:metabolism*; D005934:Glucagon / Q000737:chemistry / Q000502:physiology; D052216:Glucagon-Like Peptide 1; D000067757:Glucagon-Like Peptide-1 Receptor; D006801:Humans; D007515:Islets of Langerhans / Q000502:physiology*; D046911:Macromolecular Substances; D009928:Organ Specificity; D010446:Peptide Fragments / Q000737:chemistry / Q000502:physiology; D011498:Protein Precursors / Q000737:chemistry / Q000502:physiology; D018027:Receptors, Glucagon / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology*; D015398:Signal Transduction
C000593833:GLP1R protein, human; D000067757:Glucagon-Like Peptide-1 Receptor; D046911:Macromolecular Substances; D010446:Peptide Fragments; D011498:Protein Precursors; D018027:Receptors, Glucagon; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases