Enables protease binding activity and scaffold protein binding activity. Involved in negative regulation of neuron apoptotic process. Located in cytosol; nucleus; and perinuclear region of cytoplasm. Part of protein-containing complex. Human ortholog(s) of this gene implicated in X-linked lymphoproliferative syndrome 2 and prostate cancer. Orthologous to several human genes including XIAP (X-linked inhibitor of apoptosis). [provided by Alliance of Genome Resources, Apr 2022]