Glycosylation of the GLP-1 receptor is a prerequisite for regular receptor function.
The GLP-1 receptor on RINm5F cells is a glycoprotein with a M(r) of 63,000. Treatment of the receptor with glycopeptidase F generated a protein with a M(r) of 51,000, indicating that the GLP-1 receptor contains N-linked glycans. Tunicamycin pretreatment concentration-dependently decreased GLP-1 binding to RINm5F cells due to a decreased receptor number without change of receptor affinity. Tunicamycin exerted no effect on the GLP-1 receptor mRNA expression. The stimulation of cAMP production was decreased in tunicamycin-treated cells. Our data show that glycosylation of the GLP-1 receptor is a precondition for regular receptor function.
Göke
R
R
Department of Internal Medicine, Philipps-University of Marburg, Germany.
Just
R
R
Lankat-Buttgereit
B
B
Göke
B
B
D000581:Amidohydrolases / Q000494:pharmacology; D005934:Glucagon / Q000378:metabolism*; D052216:Glucagon-Like Peptide 1; D000067757:Glucagon-Like Peptide-1 Receptor; D004763:Glucagon-Like Peptides; D006031:Glycosylation; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008970:Molecular Weight; D010446:Peptide Fragments / Q000187:drug effects / Q000378:metabolism*; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000378:metabolism*; D018027:Receptors, Glucagon; D014407:Tumor Cells, Cultured; D014415:Tunicamycin / Q000494:pharmacology
D000067757:Glucagon-Like Peptide-1 Receptor; D007328:Insulin; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D018027:Receptors, Glucagon; D014415:Tunicamycin; C055453:glucagon-like peptide 1 (7-36)amide; D004763:Glucagon-Like Peptides; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D000581:Amidohydrolases; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase