Linked Life Data

19835884

Source:http://linkedlifedata.com/resource/pubmed/id/19835884

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-11-25
pubmed:abstractText
The insulin receptor (IR) and the homologous Type 1 insulin-like growth factor receptor (IGF-1R) are cell-surface tyrosine kinase receptors that effect signaling within the respective pathways of glucose metabolism and normal human growth. While ligand binding to these receptors is assumed to result in a structural transition within the receptor ectodomain that then effects signal transduction across the cell membrane, little is known about the molecular detail of these events. Presented here are small-angle X-ray scattering data obtained from the IR and IGF-1R ectodomains in solution. We show that, in solution, the ectodomains of IR and IGF-1R have a domain disposition that is very similar to that seen in the crystal structure of the ectodomain of IR, despite the constituent domains being in relatively sparse contact and potentially mobile. We also show that the IGF-1R ectodomain is capable of binding up to three molecules of IGF-1 in solution, with surprisingly little apparent change in relative domain disposition compared to the apo form. While the observed 3:1 ligand-binding stoichiometry appears to contradict earlier explanations of the absence of a bell-shaped dose-response curve for IGF-1R in ligand displacement assays, it is readily understood in the context of the harmonic oscillator model of the negative cooperativity of ligand binding to IGF-1R. Taken together, our findings suggest that the structural movements within these receptors upon ligand binding are small and are possibly limited to local rotation of domains.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1089-8638
pubmed:author
pubmed:issnType
Electronic
pubmed:day
18
pubmed:volume
394
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
878-92
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Solution structure of ectodomains of the insulin receptor family: the ectodomain of the type 1 insulin-like growth factor receptor displays asymmetry of ligand binding accompanied by limited conformational change.
pubmed:affiliation
Bragg Institute, Australian Nuclear Science and Technology Organisation, NSW 2234, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't