Linked Life Data

14671213

Source:http://linkedlifedata.com/resource/pubmed/id/14671213

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2003-12-12
pubmed:abstractText
Hormone-stimulated receptor internalization and desensitization occur widely in the G protein-coupled receptor (GPCR) family. A critical first step in both these processes is thought to be receptor phosphorylation, a reaction which has been extensively characterized in cell culture. However, little is known about GPCR phosphorylation in vivo. The somatostatin (SS) receptor subtype (sst)2A is widely distributed in human neuroendocrine tumors, and SS analogs are commonly used to target this receptor for both therapy and diagnosis. In cultured pituitary cells sst2A is rapidly phosphorylated and internalized after hormone binding. The aim of the present study was to go one crucial step further and characterize the phosphorylation state of this receptor in human neuroendocrine tumors using a newly developed gel-shift assay. The receptor from a somatostatinoma was completely phosphorylated. In contrast, only unphosphorylated sst2A was present in human tumors that were not exposed to autocrine stimulation. Both in vivo and in cultured cells, the phosphorylation state of the sst2A receptor was correlated with its subcellular localization: phosphorylated receptor was mostly intracellular, whereas unphosphorylated receptor was localized at the cell surface. These results are the first to demonstrate ligand-stimulated GPCR phosphorylation in human tissue in situ, providing a crucial step toward a better understanding of receptor regulation in vivo. Analysis of sst2A phosphorylation promises to provide a sensitive indicator of the effectiveness of SS analogs in diagnostic and therapeutic situations in tumor patients.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-972X
pubmed:author
pubmed:issnType
Print
pubmed:volume
88
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6073-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
In vivo phosphorylation of the somatostatin 2A receptor in human tumors.
pubmed:affiliation
Department of Integrative Biology and Pharmacology, University of Texas Health Science Center-Houston, Houston, Texas 77225, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't