Characterization of RANTES- and aminooxypentane-RANTES-triggered desensitization signals reveals differences in recruitment of the G protein-coupled receptor complex.
The trafficking of lymphocyte populations is a complex process controlled by a vast array of molecules. In this process, cells must be able to sense small changes in chemoattractant gradients. Migration through a chemotactic gradient probably employs an on-off mechanism in which chemokine receptor desensitization, internalization, and recycling may be important steps. This multistep process requires the coordinated action of many factors, including G protein-coupled receptor kinases, arrestins, clathrin, and GTP-hydrolyzing proteins such as dynamin. In this report, we show that RANTES and its derivative, aminooxypentane (AOP)-RANTES, a potent RANTES antagonist as well as an inhibitor of HIV-1 infection, both promote CCR5 desensitization involving G protein-coupled receptor kinases-2 and beta-arrestin equally well. An important difference between the two molecules is that (AOP)-RANTES is more efficient than RANTES in promoting Ser/Thr phosphorylation of the receptor and association of G protein-coupled receptor kinases-2, beta-arrestin, and clathrin to the CCR5. After stimulation with either ligand, we observe rapid, transient association of dynamin to CCR5, implicating this protein in receptor sensitization, but this association is faster and longer-lasting following (AOP)-RANTES stimulation. In summary, we show that chemokine receptor internalization takes place through the formation of clathrin vesicles and involves dynamin activity. We provide compelling evidence that the differences between RANTES and (AOP)-RANTES in G alpha i activation condition subsequent signaling events, including internalization and receptor recycling.
Vila-Coro
A J
AJ
Department of Immunology and Oncology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Cientificas/Universidad Autonoma de Madrid, Spain.
Mellado
M
M
Martín de Ana
A
A
Martínez-A
C
C
Rodríguez-Frade
J M
JM
D019390:Arrestins / Q000378:metabolism; D065100:CCR5 Receptor Antagonists; D018946:Chemokine CCL5 / Q000031:analogs & derivatives* / Q000502:physiology*; D002966:Clathrin / Q000378:metabolism; D018699:Coated Vesicles / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D003888:Desensitization, Immunologic; D015536:Down-Regulation / Q000276:immunology; D034281:Dynamins; D020558:GTP Phosphohydrolases / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D010766:Phosphorylation; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D019713:Receptors, CCR5 / Q000235:genetics / Q000378:metabolism; D012694:Serine / Q000378:metabolism; D015398:Signal Transduction / Q000276:immunology*; D013912:Threonine / Q000378:metabolism; D013997:Time Factors; D014162:Transfection; D051552:beta-Adrenergic Receptor Kinases
D019390:Arrestins; D065100:CCR5 Receptor Antagonists; D018946:Chemokine CCL5; D002966:Clathrin; D019713:Receptors, CCR5; C111989:aminooxypentane-RANTES; D013912:Threonine; D012694:Serine; D020794:Receptor Protein-Tyrosine Kinases; D017868:Cyclic AMP-Dependent Protein Kinases; D051552:beta-Adrenergic Receptor Kinases; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins; D034281:Dynamins