Acts as a positive regulator of apoptosis. Also acts as a regulator of cellular reactive oxygen species. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Inhibited by thiazolidinedione-type compounds: inhibited by furan- and pyridone- thiazolidinediones. Highly expressed in placenta. Lower levels in heart, lung, skeletal muscle, kidney and pancreas. Directly regulated by p53/TP53: induced following cisplatin treatment in a p53/TP53-dependent manner. p53/TP53 activates expression by directly binding to its regulatory regions. Autophosphorylated. Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family. DAP kinase subfamily.