Enables protein serine/threonine kinase activity. Acts upstream of or within several processes, including cellular response to UV; negative regulation of cellular protein metabolic process; and negative regulation of stress-activated MAPK cascade. Predicted to be located in nucleus. Is expressed in several structures, including alimentary system; genitourinary system; nervous system; respiratory system; and sensory organ. Orthologous to human PBK (PDZ binding kinase). [provided by Alliance of Genome Resources, Apr 2022]