Linked Life Data

8795068

Source:http://linkedlifedata.com/resource/pubmed/id/8795068

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1996-12-30
pubmed:abstractText
There is controversy as to whether or not a pertussis toxin sensitive G-protein is involved in the signaling pathway of insulin-like growth factor-I. We have used normal rat kidney epithelial (NRKE) cells to ask whether or not a pertussis toxin sensitive G-protein was involved in IGF-I stimulated DNA synthesis. NRKE cells express both IGF and IGF-II/M6P receptors and respond to IGF-I with increased thymidine incorporation into DNA. Under many circumstances incubation of cells/cell membranes with GTP analogues will inhibit binding of ligands that are linked to a G-protein-receptor pathway. However, when NRKE membrane preparations were incubated with 125I-IGF-I or 125I-IGF-II in the presence or absence of GTP gamma S, ATP and GTP, binding of the radioligands was not affected by the GTP-analogue. IGF-I and factors from serum of hypophysectomized rats (HRS) stimulated [3H]thymidine incorporation into DNA of NRKE cells. Under serum-free conditions in the presence of EGF (2 ng/ml) and PDGF (1 ng/ml) pertussis toxin over a wide range of doses had no effect upon IGF-I stimulated [3H]thymidine incorporation into DNA of NRKE cells. In addition, PT at a dose of 100 ng/ml had no effect on IGF-I(0.2-50 ng/ml) stimulated DNA synthesis of NRKE cells. However, PT at doses of 5, 50, 500, 5000 and 50,000 ng/ml was capable to ADP-ribosylate a 40 kDa protein in NRKE cell plasma membrane preparations corresponding to known PT-sensitive G-proteins. We conclude, that (1) PT-sensitive G-proteins and both IGF-I and IGF-II/M6P receptors are present in NRKE cell plasma membrane preparations, and most importantly, that (2) PT-sensitive G-proteins are not involved in the mitogenic signaling pathway of IGF-I in NRKE cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0167-0115
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
65-71
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Pertussis toxin sensitive G-proteins are not involved in the mitogenic signaling pathway of insulin-like growth factor-I in normal rat kidney epithelial (NRKE) cells.
pubmed:affiliation
Children's Hospital, Ludwig Maximilians University of Munich, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't