Differential G-protein-coupled receptor phosphorylation provides evidence for a signaling bar code.
J Biol Chem
; 286(13): 11506-18, 2011 Apr 01.
Article
em En
| MEDLINE
| ID: mdl-21177246
ABSTRACT
G-protein-coupled receptors are hyper-phosphorylated in a process that controls receptor coupling to downstream signaling pathways. The pattern of receptor phosphorylation has been proposed to generate a "bar code" that can be varied in a tissue-specific manner to direct physiologically relevant receptor signaling. If such a mechanism existed, receptors would be expected to be phosphorylated in a cell/tissue-specific manner. Using tryptic phosphopeptide maps, mass spectrometry, and phospho-specific antibodies, it was determined here that the prototypical G(q/11)-coupled M(3)-muscarinic receptor was indeed differentially phosphorylated in various cell and tissue types supporting a role for differential receptor phosphorylation in directing tissue-specific signaling. Furthermore, the phosphorylation profile of the M(3)-muscarinic receptor was also dependent on the stimulus. Full and partial agonists to the M(3)-muscarinic receptor were observed to direct phosphorylation preferentially to specific sites. This hitherto unappreciated property of ligands raises the possibility that one mechanism underlying ligand bias/functional selectivity, a process where ligands direct receptors to preferred signaling pathways, may be centered on the capacity of ligands to promote receptor phosphorylation at specific sites.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Transdução de Sinais
/
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP
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Receptor Muscarínico M3
Limite:
Animals
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article