PKC gamma (protein kinase C-gamma) is a 78-80 kDa member of the PKC subfamily, AGC Ser/Thr protein kinase family of enzymes. It is a Ca++-activated and phospholipid-dependent neuronal enzyme that catalyzes the phosphorylation of multiple proteins. Human PKC gamma is 697 amino acids (aa) in length. It contains two general regions: a lipid and Ca++-binding regulatory region (aa 35-150 and 170-260, respectively), and an ATP-binding catalytic region (aa 351-614). PDK1-mediated phosphorylation of PKC gamma on Thr514 activates the enzyme. In addition, oxidative stress also mediates activation by inducing interchain disulfide-bond homodimerization. Over aa 621-697, human PKC gamma is 99% and 95% aa identical to mouse and canine PKC gamma, respectively. PKC gamma is predominantly expressed in brain tissue.