Induces CD27-mediated apoptosis. Inhibits BCL2L1 isoform Bcl- x(L) anti-apoptotic activity. Inhibits activation of NF-kappa-B and promotes T-cell receptor-mediated apoptosis. {ECO:0000269|PubMed:12011449, ECO:0000269|PubMed:14739602, ECO:0000269|PubMed:15034012, ECO:0000269|PubMed:15958577, ECO:0000269|PubMed:16491128}. This is the function of ENSG00000184990 (SIVA1, SIVA1 apoptosis inducing factor).