Plays a role as a mediator of E2F1-induced apoptosis in the absence of p53/TP53 (PubMed:15565177). Plays a role as a mediator of E2F1-induced apoptosis in the absence of p53/TP53. Inhibits TLR9 response to nucelic acids and regulates TLR9-mediated innate immune response (By similarity).