Receptor-interacting serine/threonine-protein kinase 3 is an enzyme that is encoded by the RIPK3 gene in humans. The product of this gene is a member of the receptor-interacting protein (RIP) family of serine/threonine protein kinases. It contains a C-terminal domain unique from other RIP family members. The encoded protein is predominantly localized to the cytoplasm, and can undergo nucleocytoplasmic shuttling dependent on novel nuclear localization and export signals. It is a component of the tumor necrosis factor (TNF) receptor-I signaling complex, and can induce necroptosis by interaction with RIPK1 and MLKL in a protein complex termed the necrosome. Interactions between RIPK1 and RIPK3 also form a necrosome, which triggers apoptosis.