May play a critical role in death receptor-induced apoptosis and may target CASP8 and CASP10 to the nucleus. May regulate degradation of intermediate filaments during apoptosis. May play a role in the general transcription machinery in the nucleus and might be an important regulator of the activity of GTF3C3. Interacts with CASP8, CASP10 and GTF3C3. Homodimerizes and heterodimerizes with DEDD. Nuclear, accumulated in subnuclear structures resembling nucleoli. Expressed in most tissues. High levels were found in liver, kidney, heart, ovary, spleen, testes, skeletal muscle and peripheral blood leukocytes. Expression was absent or low in colon and small intestine. Expression is relatively high in the tumor cell lines chronic myologenous leukemia K-562 and the colorectal adenocarcinoma SW480. Expression is moderate in the cervical carcinoma HeLa, the Burkitt's lymphoma Raji, the lung carcinoma A-549, and the melanoma G-361. In contrast, two leukemia cell lines, HL-60 (promyelocytic leukemia) and MOLT-4 (lymphoblastic leukemia), show relatively low levels. Interactions with CASP8 and CASP10 are mediated by the DED domain.