Linked Life Data

9673790

Source:http://linkedlifedata.com/resource/pubmed/id/9673790

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-10-22
pubmed:abstractText
Previous work suggested that sulfhydryl groups and disulfide bridges have important functions in opioid binding to the delta opioid receptor. The question regarding which cysteines are essential for ligand binding was approached by replacement of cysteine residues in the cloned delta opioid receptor using site-directed mutagenesis. The wild-type and mutant receptors were expressed stably in Chinese hamster ovary cells. The two extracellular cysteine residues and the six located in transmembrane domains were mutated to serine or alanine, one at a time. Replacement of either of the extracellular cysteines produced a receptor devoid of delta agonist and antagonist binding activity. Immunofluorescence cytochemistry, performed with anti delta opioid receptor antibodies in washed cell monolayers in one of these mutants (Cys-Ser121), and immunoblots, performed on cell extracts, indicate that the receptor was expressed and seems to be associated with the cell membrane. The existence of an essential extracellular disulfide bridge, previously postulated by analogy to other G protein coupled receptors, is strongly supported by our results. Replacement of any one of the six transmembrane cysteines was virtually without effect on the ability of the receptor to bind delta agonists and antagonists. Since there is strong evidence that the transmembrane domains are involved in ligand binding, these results suggest that the cysteine residues, even those near or at the binding site, are not essential for receptor binding. Furthermore, these results support the idea that the striking effects of sulfhydryl reagents on ligand binding of opioid receptors are likely to be due to steric hindrance by the large moieties transferred to the sulfhydryl groups of cysteine residues by these reagents.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0008-4212
pubmed:author
pubmed:issnType
Print
pubmed:volume
76
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
269-77
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Functional significance of cysteine residues in the delta opioid receptor studied by site-directed mutagenesis.
pubmed:affiliation
Department of Psychiatry, New York University Medical Center, NY 10016, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't