Direct targets of phosphoinositide 3-kinase products in membrane traffic and signal transduction.

Phosphoinositide 3-kinases are a family of lipid kinases that phosphorylate the 3' position of the inositol ring on phosphatidylinositol and higher-phosphorylated polyphosphoinositides. The multiplicity of cellular functions influenced by the activity of these enzymes has captured the attention of researchers working on two important fields of cell biology--signal transduction and membrane traffic. This review discusses how the recent identification of proteins that interact directly with 3'-polyphosphoinositides has revealed novel potential interconnections between these fundamental cellular processes.