Using structure to define the function of phosphoinositide 3-kinase family members

The phosphoinositide (PI) 3-kinase family.

Phosphoinositide (PI) 3-kinase was first observed in 1984 as a minor inositol lipid kinase activity associated with immunoprecipitated oncogene products (e.g. Src, Abl and polyoma mT antigen) and present in activated growth factor receptor complexes (e.g. PDGF receptor). In 1988, the enzyme associated with this activity was found to have the novel ability to phosphorylate the 3 position hydroxy...

Phosphoinositide 3-kinase activation and platelet function.

Syk regulation of phosphoinositide 3-kinase-dependent NK cell function.

Emerging evidence suggests that NK-activatory receptors use KARAP/DAP12, CD3zeta, and FcepsilonRIgamma adaptors that contain immunoreceptor tyrosine-based activatory motifs to mediate NK direct lysis of tumor cells via Syk tyrosine kinase. NK cells may also use DAP10 to drive natural cytotoxicity through phosphoinositide 3-kinase (PI3K). In contrast to our recently identified PI3K pathway contr...

p85beta phosphoinositide 3-kinase regulates CD28 coreceptor function.

CD28 is a receptor expressed on T cells that regulates their differentiation after antigen stimulation to long-term-survival memory T cells. CD28 enhances T-cell receptor signals and reduces expression of CBL ubiquitin ligases, which negatively control T-cell activation. In the absence of CD28 ligation during the primary stimulation, CBL levels remain high and T cells fail to mount an efficient...

Phosphoinositide 3-kinase signalling pathways.

Phosphoinositide 3-kinases (PI3Ks) phosphorylate the 3'-OH position of the inositol ring of inositol phospholipids, producing three lipid products: PtdIns(3)P, PtdIns(3,4)P(2) and PtdIns(3,4,5)P(3). These lipids bind to the pleckstrin homology (PH) domains of proteins and control the activity and subcellular localisation of a diverse array of signal transduction molecules. Three major classes o...