Stimulation- and palmitoylation-dependent changes in oligomeric conformation of serotonin 5-HT1A receptors.
Biochim Biophys Acta
; 1783(8): 1503-16, 2008 Aug.
Article
em En
| MEDLINE
| ID: mdl-18381076
ABSTRACT
In the present study we analyzed the oligomerization state of the serotonin 5-HT1A receptor and studied oligomerization dynamics in living cells. We also investigated the role of receptor palmitoylation in this process. Biochemical analysis performed in neuroblastoma N1E-115 cells demonstrated that both palmitoylated and non-palmitoylated 5-HT1A receptors form homo-oligomers and that the prevalent receptor species at the plasma membrane are dimers. A combination of an acceptor-photobleaching FRET approach with fluorescence lifetime measurements verified the interaction of CFP- and YFP-labeled wild-type as well as acylation-deficient 5-HT1A receptors at the plasma membrane of living cells. Using a novel FRET technique based on the spectral analysis we also confirmed the specific nature of receptor oligomerization. The analysis of oligomerization dynamics revealed that apparent FRET efficiency measured for wild-type oligomers significantly decreased in response to agonist stimulation, and our combined results suggest that this decrease was mediated by accumulation of FRET-negative complexes rather than by dissociation of oligomers to monomers. In contrast, the agonist-mediated decrease of FRET signal was completely abolished in oligomers composed by non-palmitoylated receptor mutants, demonstrating the importance of palmitoylation in modulation of the structure of oligomers.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Receptor 5-HT1A de Serotonina
Limite:
Animals
Idioma:
En
Revista:
Biochim Biophys Acta
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Alemanha