Format

Send to

Choose Destination
See comment in PubMed Commons below
EMBO J. 1993 Jun;12(6):2265-73.

Receptor stimulated accumulation of phosphatidylinositol (3,4,5)-trisphosphate by G-protein mediated pathways in human myeloid derived cells.

Author information

1
Biochemistry Department, AFRC Institute of Animal Physiology and Genetics Research, Babraham, Cambridge, UK.

Abstract

Phosphoinositide 30H-kinase (PI3K) activities are thought to be critical regulatory enzymes in a new intracellular signalling pathway, the activation of which results in the rapid accumulation of a putative signalling molecule, phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5) P3]. To date, activation of PI3K has always correlated with its recruitment into complexes containing protein tyrosine kinases (PTK). Here we report that agonists which utilize G-protein mediated transduction pathways can stimulate very rapid and large accumulations of PtdIns(3,4,5)P3 via a novel mechanism, possibly involving direct coupling between the G-protein and a PI3K activity. In addition, some of these agonists also stimulate small increases in PI3K activity in anti-phosphotyrosine and anti-src-type PTK antibody directed immunoprecipitates, indicating activation of PI3K via a 'conventional' PTK mediated mechanism; these pathways however, play only a minor role in the initial, agonist sensitive production of PtdIns(3,4,5)P3 in myeloid derived cells.

PMID:
8389691
PMCID:
PMC413455
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments

    Supplemental Content

    Full text links

    Icon for PubMed Central
    Loading ...
    Support Center