Expression, action and function of phosphoinositide 3-kinase p110delta

Phosphoinositides (PIs) are phospholipid components of eukaryotic cell membranes. By functioning as second messengers they play an important role in signal transduction. Phosphatidylinositol (PtdIns) is the building block of phosphoinositides and consists of a hydrophobic tail, composed of two fatty acids chains, that is anchored into the lipid bilayer, connected to a hydrophilic inositol head group that resides in the cytoplasm. The inositol ring has free hydroxyl groups that can be phosphorylated in different combinations. The term phosphoinositide (PI) applies to any phosphorylated derivate of phosphatidylinositol.