Phosphatidylinositol 3-kinases (PI3Ks) phosphorylate the inositol ring of phosphatidylinositol at the 3-prime position, and play important roles in cell growth, proliferation, differentiation, motility, survival and intracellular trafficking. The PI3Ks are divided into three classes: I, II and III, and only the class I PI3Ks are involved in oncogenesis. This gene encodes the 101 kD regulatory subunit of the class I PI3K gamma complex, which is a dimeric enzyme, consisting of a 110 kD catalytic subunit gamma and a regulatory subunit of either 55, 87 or 101 kD. This protein recruits the catalytic subunit from the cytosol to the plasma membrane through high-affinity interaction with G-beta-gamma proteins. Multiple alternatively spliced transcript variants encoding two distinct isoforms have been found. [provided by RefSeq, Oct 2011],domain:The heterodimerization region allows the binding to the catalytic subunit.,enzyme regulation:Greatly activated by G gamma proteins.,function:Regulatory subunit of the PI3K gamma complex.,subunit:Heterodimer of a catalytic subunit (PIK3CG/p120) and a regulatory (PIK3R5a/p101) subunit. Interacts with G beta gamma proteins.,tissue specificity:Highly expressed in leukocytes, followed by spleen, lymph node, thymus ans bone marrow.,
