Role of cysteine 341 and arginine 348 of GLP-1 receptor in G-protein coupling.
We have demonstrated the ability of peptides derived from the third intracellular loop of GLP-1 receptor to differently modulate activity of four different types of G-proteins overexpressed in sf9 cells. In this respect, the involvement of Cys(341) in inhibition of G(s) and Cys(341) in activation of G(s) and in inhibition of G(i1,) G(o), and G(11), respectively, indicates their potential role in discrimination between different types of G-proteins. Moreover, these two amino acids from the third intracellular loop might represent an important novel targets for covalent modification by downstream regulators in signaling through GLP-1 receptor.
Bavec
Aljosa
A
Institute of Biochemistry, Medical Faculty, University of Ljubljana, Vrazov trg 2, 1000, Ljubljana, Slovenia. aljosa.bavec@mf.uni-lj.si
Jiang
Yang
Y
Langel
Ulo
U
Zorko
Matjaz
M
D000818:Animals; D001120:Arginine / Q000502:physiology*; D002417:Cattle; D002478:Cells, Cultured; D003545:Cysteine / Q000502:physiology*; D000067757:Glucagon-Like Peptide-1 Receptor; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D018027:Receptors, Glucagon / Q000737:chemistry* / Q000378:metabolism* / Q000502:physiology; D011994:Recombinant Proteins / Q000235:genetics; D015398:Signal Transduction; D018411:Spodoptera
D000067757:Glucagon-Like Peptide-1 Receptor; D018027:Receptors, Glucagon; D011994:Recombinant Proteins; D001120:Arginine; D020962:Heterotrimeric GTP-Binding Proteins; D003545:Cysteine