Linked Life Data

10412719

Source:http://linkedlifedata.com/resource/pubmed/id/10412719

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-9-23
pubmed:abstractText
Agonist-dependent internalization is an important phase of beta 2-adrenergic receptor (beta 2AR) regulation. Recent reports have indicated that early steps of beta 2AR endocytosis may involve mechanisms different from those which regulate the internalization of constitutively recycling receptors, such as transferrin receptor (TfR). In the present study, we addressed this issue by comparing, in the same cells, the endocytic pathway of beta 2AR with that of the TfR. Upon incubation at 15 degrees C, activated beta 2ARs accumulated in peripheral endosomes of HEK-293 cells while they were targeted to perinuclear organelles at 37 degrees C. The temperature block was not specific to beta 2ARs, since both peripheral and perinuclear beta 2AR-containing endosomes comigrated on sucrose gradients with those containing transferrin receptors and were loaded with horseradish peroxidase-coupled transferrin. Endocytosis of beta 2ARs was saturable in HEK-293 cells and did not increase upon overexpression of beta-arrestin 1. TfR endocytosis was unaffected by the simultaneous internalization of overexpressed beta 2AR, indicating that the limiting components which regulate endocytosis of these two receptors are different. In conclusion, ligand activated beta 2AR and constitutively recycling receptors, such as TfR, enter the endocytic pathway via distinct saturable mechanisms but converge in the same endosomal compartments. Our results also indicate that a still unidentified component(s) controls beta 2AR endocytosis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1060-6823
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
255-69
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:10412719-3,3'-Diaminobenzidine, pubmed-meshheading:10412719-Adrenergic beta-Agonists, pubmed-meshheading:10412719-Arrestin, pubmed-meshheading:10412719-Cell Line, pubmed-meshheading:10412719-Centrifugation, Density Gradient, pubmed-meshheading:10412719-Endocytosis, pubmed-meshheading:10412719-Humans, pubmed-meshheading:10412719-Iodocyanopindolol, pubmed-meshheading:10412719-Isoproterenol, pubmed-meshheading:10412719-Microscopy, Fluorescence, pubmed-meshheading:10412719-Phosphorylation, pubmed-meshheading:10412719-Propanolamines, pubmed-meshheading:10412719-Propranolol, pubmed-meshheading:10412719-Protein Processing, Post-Translational, pubmed-meshheading:10412719-Receptors, Adrenergic, beta-2, pubmed-meshheading:10412719-Receptors, Transferrin, pubmed-meshheading:10412719-Recombinant Fusion Proteins, pubmed-meshheading:10412719-Temperature, pubmed-meshheading:10412719-Transfection
pubmed:year
1999
pubmed:articleTitle
Beta 2-adrenergic receptor endocytic pathway is controlled by a saturable mechanism distinct from that of transferrin receptor.
pubmed:affiliation
Department of Biochemistry and Biophysics, University of California, San Francisco 94143-0534, USA. marullo@cochin.inserm.fr
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't