May modulate activity of cullin-RING E3 ubiquitin ligase (CRL) complexes. May down-regulate activation of NF-kappa-B. Modulates Na(+) transport in epithelial cells by regulation of apical cell surface expression of amiloride-sensitive sodium channel (ENaC) subunits. Interacts (via COMM domain) with COMMD1 (via COMM domain). Interacts with NFKB1/p105. Interacts with CCDC22, CCDC93, SCNN1B, CUL3, CUL4A, CUL4B, CUL5. Expressed in kidney collecting duct cells and in the nuclei of proximal convoluted tubule cells in the kidney cortex (at protein level).