Seems to negatively regulate apoptosis by promoting FADD phosphorylation. Enhances androgen receptor-mediated transcription. May act as a transcriptional corepressor for NK homeodomain transcription factors. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts with Nkx1-2. Interacts with FAS and DAXX. Probably part of a complex consisting of HIPK3, FAS and FADD. Interacts with UBL1/SUMO-1 (By similarity). Interacts with and stabilizes ligand-bound androgen receptor (AR). Autophosphorylated. Autophosphorylation is not required for catalytic activity. May be sumoylated. Belongs to the protein kinase superfamily. CMGC Ser/Thr protein kinase family. HIPK subfamily.