Function, Regulation and Biological Roles of PI3Kγ Variants

Phosphatidylinositide 3-kinase (PI3K) gamma is the only class IB PI3K member playing significant roles in the G-protein-dependent regulation of cell signaling in health and disease. Originally found in the immune system, increasing evidence suggest a wide array of functions in the whole organism. PI3K gamma occur as two different heterodimeric variants: PI3K gamma (p87) and PI3K gamma (p101), which share the same p110 gamma catalytic subunit but differ in their associated non-catalytic subunit. Here we concentrate on specific PI3K gamma features including its regulation and biological functions. In particular, the roles of its non-catalytic subunits serving as the main regulators determining specificity of class IB PI3K gamma enzymes are highlighted.