May modulate activity of cullin-RING E3 ubiquitin ligase (CRL) complexes. Inhibits TNF-induced NFKB1 activation. Homodimer. Interacts (via COMM domain) with COMMD1 (via COMM domain). Does not interact with NFKBIB. Interacts with RELA, RELB, NFKB1/p105. Does not interact with NFKBIB. Interacts with CCDC22, CCDC93, SCNN1B, CUL4A.