Discrete amino acid sequences of the alpha 1-adrenergic receptor determine the selectivity of coupling to phosphatidylinositol hydrolysis.

Details

Serval ID
serval:BIB_2C75A0BCD3B5
Type
Article: article from journal or magazin.
Collection
Publications
Title
Discrete amino acid sequences of the alpha 1-adrenergic receptor determine the selectivity of coupling to phosphatidylinositol hydrolysis.
Journal
Journal of Biological Chemistry
Author(s)
Cotecchia S., Ostrowski J., Kjelsberg M.A., Caron M.G., Lefkowitz R.J.
ISSN
0021-9258 (Print)
ISSN-L
0021-9258
Publication state
Published
Issued date
1992
Peer-reviewed
Oui
Volume
267
Number
3
Pages
1633-1639
Language
english
Abstract
We have constructed a variety of chimeric beta 2/alpha 1 adrenergic receptors (AR) in which selected portions of the third intracellular loop of the alpha (1B)AR were substituted into the corresponding regions of the beta 2AR. The mutant receptors were both transiently and permanently expressed in COS-7 or L-cells, respectively, and tested for their ability to mediate epinephrine-induced activation of polyphosphoinositide (PI) hydrolysis and adenylylcyclase. We have determined that 27 amino acids of the alpha (1B)AR (residues 233-259) derived from the N-terminal portion of the third intracellular loop represent the structural determinant conferring to the beta 2AR the ability to activate PI hydrolysis. This finding suggests that in the alpha (1B)AR the N-terminal portion of the third intracellular loop plays a major role in determining the selectivity of receptor-G protein coupling. However, replacement of alpha 1B sequences in the third intracellular loop of the beta 2AR did not abolish the latter receptor's coupling to activation of adenylylcyclase, thus resulting in chimeric adrenergic receptors which activated both PI hydrolysis and adenylylcyclase. These results indicate that, even if the N-terminal portion of the third intracellular loop is a major determinant of the selectivity of receptor-G protein coupling, other structural domains of the receptors also modulate this property. The comparison of the amino acid sequences which determine the selectivity of G protein coupling in functionally similar receptors may help to elucidate the structural basis for activation of specific G protein-effector systems.
Keywords
Adenylate Cyclase/metabolism, Amino Acid Sequence, Animals, Cell Line, Chimera, DNA/genetics, DNA/isolation & purification, Epinephrine/pharmacology, Humans, Hydrolysis, Inositol Phosphates/metabolism, Kinetics, L Cells (Cell Line), Mice, Models, Structural, Molecular Sequence Data, Phosphatidylinositols/metabolism, Polymerase Chain Reaction/methods, Receptors, Adrenergic, alpha/genetics, Receptors, Adrenergic, alpha/metabolism, Receptors, Adrenergic, beta/genetics, Receptors, Adrenergic, beta/metabolism, Recombinant Fusion Proteins/metabolism, Thymidine Kinase/deficiency, Thymidine Kinase/genetics, Transfection
Pubmed
Web of science
Create date
24/01/2008 11:05
Last modification date
20/08/2019 13:11
Usage data