Linked Life Data

1695626

Source:http://linkedlifedata.com/resource/pubmed/id/1695626

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1990-8-30
pubmed:abstractText
Insulin-like growth factor (IGF)-binding proteins (BPs) bind IGF-I and IGF-II with high affinity. They are present in extracellular fluids and modulate the interactions of their ligands with the type 1 IGF cell surface receptor. These studies utilized IGF-I analogs that have reduced binding affinity for either the type 1 IGF receptor or binding proteins to study the ligand specificity of IGF-BP-1 and the role of IGF-BP-1 in modulating the biological activity of IGF-I. The data indicate that the regions of IGF-I which are responsible for binding to IGF-BP-1 and to human serum-binding proteins are distinct but overlapping and are clearly distinct from the type I receptor binding sites. In the absence of exogenously added IGF-BP-1, the analogs with reduced affinity for IGF-BP-1 are more potent than IGF-I in stimulating DNA synthesis by porcine aortic smooth muscle cells. In contrast, when cells are concomitantly exposed to IGF-BP-1, two of the analogs with reduced affinity for binding protein give only 40-65% of the maximal IGF-I response. [Leu24, 1-62]IGF-I, which has a 100-fold reduced affinity for the type 1 IGF receptor, gave a value that was 62% of the maximal IGF-BP-1 potentiated response. A second biological response, that of stimulating binding protein secretion by IGF-I, was also examined. [Leu24, 1-62]IGF-I is more potent than IGF-I whereas the activity of the analogs with lower affinity for IGF-BP-1 is significantly reduced. Thus, the ability to activate DNA synthesis and binding protein secretion maximally in the presence of IGF-BP-1 is dependent on the affinity of IGFs for both type 1 receptors and binding proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12210-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:1695626-Amino Acid Sequence, pubmed-meshheading:1695626-Animals, pubmed-meshheading:1695626-Binding, Competitive, pubmed-meshheading:1695626-Carrier Proteins, pubmed-meshheading:1695626-Cells, Cultured, pubmed-meshheading:1695626-DNA, pubmed-meshheading:1695626-DNA Mutational Analysis, pubmed-meshheading:1695626-Humans, pubmed-meshheading:1695626-Insulin-Like Growth Factor Binding Proteins, pubmed-meshheading:1695626-Insulin-Like Growth Factor I, pubmed-meshheading:1695626-Molecular Sequence Data, pubmed-meshheading:1695626-Protein Conformation, pubmed-meshheading:1695626-Receptors, Cell Surface, pubmed-meshheading:1695626-Receptors, Somatomedin, pubmed-meshheading:1695626-Somatomedins, pubmed-meshheading:1695626-Structure-Activity Relationship, pubmed-meshheading:1695626-Swine
pubmed:year
1990
pubmed:articleTitle
Discrete alterations of the insulin-like growth factor I molecule which alter its affinity for insulin-like growth factor-binding proteins result in changes in bioactivity.
pubmed:affiliation
Department of Medicine, University of North Carolina School of Medicine, Chapel Hill 27599.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.