|
rdf:type |
|
|
lifeskim:mentions |
|
|
pubmed:issue |
2
|
|
pubmed:dateCreated |
2005-1-26
|
|
pubmed:abstractText |
Attenuation of CRH receptor type 1 (CRH-R1) signaling activity might involve desensitization and uncoupling of CRH-R1 from intracellular effectors. We investigated the desensitization of native CRH-R in human myometrial cells from pregnant women and recombinant CRH-R1alpha stably overexpressed in human embryonic kidney (HEK) 293 cells. In both cell types, CRH-R1-mediated adenylyl cyclase activation was susceptible to homologous desensitization induced by pretreatment with high concentrations of CRH. Time course studies showed half-maximal desensitization occurring after approximately 40 min of pretreatment and full recovery of CRH-R1alpha functional response within 2 h of removal of CRH pretreatment. In HEK 293 cells, desensitization of CRH-R1alpha was associated with receptor phosphorylation and subsequent endocytosis. To analyze the mechanism leading to CRH-R1alpha desensitization, we overexpressed a truncated beta-arrestin (319-418) and performed coimmunoprecipitation and G protein-coupled receptor kinase (GRK) translocation studies. We found that GRK3 and GRK6 are the main isoforms that interact with CRH-R1alpha, and that recruitment of GRK3 requires Gbetagamma-subunits as well as beta-arrestin. Site-directed mutagenesis of Ser and Thr residues in the CRH-R1alpha C terminus, identified Thr399 as important for GRK-induced receptor phosphorylation and desensitization.We conclude that homologous desensitization of CRH-R1alpha involves the coordinated action of multiple GRK isoforms, Gbeta gamma dimers and beta-arrestin. Based on our identification of key amino acid(s) for GRK-dependent phosphorylation, we demonstrate the importance of the CRH-R1alpha carboxyl tail for regulation of receptor activity.
|
|
pubmed:language |
eng
|
|
pubmed:journal |
|
|
pubmed:citationSubset |
IM
|
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adenylate Cyclase,
http://linkedlifedata.com/resource/pubmed/chemical/Arrestins,
http://linkedlifedata.com/resource/pubmed/chemical/CRF receptor type 1,
http://linkedlifedata.com/resource/pubmed/chemical/Cyclic AMP,
http://linkedlifedata.com/resource/pubmed/chemical/Heparin,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Isoforms,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Corticotropin-Releasing...,
http://linkedlifedata.com/resource/pubmed/chemical/Serine,
http://linkedlifedata.com/resource/pubmed/chemical/Threonine,
http://linkedlifedata.com/resource/pubmed/chemical/Tyrosine,
http://linkedlifedata.com/resource/pubmed/chemical/beta-arrestin
|
|
pubmed:status |
MEDLINE
|
|
pubmed:month |
Feb
|
|
pubmed:issn |
0888-8809
|
|
pubmed:author |
|
|
pubmed:issnType |
Print
|
|
pubmed:volume |
19
|
|
pubmed:owner |
NLM
|
|
pubmed:authorsComplete |
Y
|
|
pubmed:pagination |
474-90
|
|
pubmed:dateRevised |
2006-11-15
|
|
pubmed:meshHeading |
pubmed-meshheading:15498832-Adenylate Cyclase,
pubmed-meshheading:15498832-Animals,
pubmed-meshheading:15498832-Arrestins,
pubmed-meshheading:15498832-Cell Line,
pubmed-meshheading:15498832-Cyclic AMP,
pubmed-meshheading:15498832-Dimerization,
pubmed-meshheading:15498832-Electrophoresis, Polyacrylamide Gel,
pubmed-meshheading:15498832-Endocytosis,
pubmed-meshheading:15498832-Female,
pubmed-meshheading:15498832-Heparin,
pubmed-meshheading:15498832-Humans,
pubmed-meshheading:15498832-Immunoprecipitation,
pubmed-meshheading:15498832-Microscopy, Confocal,
pubmed-meshheading:15498832-Microscopy, Fluorescence,
pubmed-meshheading:15498832-Models, Biological,
pubmed-meshheading:15498832-Muscle Cells,
pubmed-meshheading:15498832-Mutagenesis, Site-Directed,
pubmed-meshheading:15498832-Mutation,
pubmed-meshheading:15498832-Phosphorylation,
pubmed-meshheading:15498832-Polymerase Chain Reaction,
pubmed-meshheading:15498832-Protein Isoforms,
pubmed-meshheading:15498832-Protein Structure, Tertiary,
pubmed-meshheading:15498832-Protein Transport,
pubmed-meshheading:15498832-Rats,
pubmed-meshheading:15498832-Receptors, Corticotropin-Releasing Hormone,
pubmed-meshheading:15498832-Serine,
pubmed-meshheading:15498832-Sheep,
pubmed-meshheading:15498832-Signal Transduction,
pubmed-meshheading:15498832-Threonine,
pubmed-meshheading:15498832-Time Factors,
pubmed-meshheading:15498832-Transfection,
pubmed-meshheading:15498832-Tyrosine
|
|
pubmed:year |
2005
|
|
pubmed:articleTitle |
Regulation of corticotropin-releasing hormone receptor type 1alpha signaling: structural determinants for G protein-coupled receptor kinase-mediated phosphorylation and agonist-mediated desensitization.
|
|
pubmed:affiliation |
Sir Quinton Hazell Molecular Medicine Research Centre, Department of Biological Sciences, The University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom.
|
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
|
