Linked Life Data

10967122

Source:http://linkedlifedata.com/resource/pubmed/id/10967122

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
2000-12-18
pubmed:abstractText
Systematic analysis of structural changes induced by activating mutations has been frequently utilized to study activation mechanisms of G-protein-coupled receptors (GPCRs). In the thyrotropin receptor and the lutropin receptor (LHR), a large number of naturally occurring mutations leading to constitutive receptor activation were identified. Saturating mutagenesis studies of a highly conserved Asp in the junction of the third intracellular loop and transmembrane domain 6 suggested a participation of this anionic residue in a salt bridge stabilizing the inactive receptor conformation. However, substitution of all conserved cationic residues at the cytoplasmic receptor surface did not support this hypothesis. Asp/Glu residues are a common motif at the N-terminal ends of alpha-helices terminating and stabilizing the helical structure (helix capping). Since Asp/Glu residues in the third intracellular loop/transmembrane domain 6 junction are not only preserved in glycoprotein hormone receptors but also in other GPCRs we speculated that this residue probably participates in an N-terminal helix-capping structure. Poly-Ala stretches are known to form and stabilize alpha-helices. Herein, we show that the function of the highly conserved Asp can be mimicked by poly-Ala substitutions in the LHR and thyrotropin receptor. CD and NMR studies of peptides derived from the juxtamembrane portion of the LHR confirmed the helix extension by the poly-Ala substitution and provided further evidence for an involvement of Asp in a helix-capping structure. Our data implicate that in addition to well established interhelical interactions the inactive conformation of GPCRs is also stabilized by specific intrahelical structures.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
37860-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Requirement of specific intrahelical interactions for stabilizing the inactive conformation of glycoprotein hormone receptors.
pubmed:affiliation
Institut für Pharmakologie, Universitätsklinikum Benjamin Franklin, Freie Universität Berlin, Thielallee 69-73, 14195 Berlin, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't