E3 ubiquitin-protein ligase that mediates the ubiquitination and proteasomal degradation of CYLD. S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)-ubiquitinyl-[acceptor protein]-L-lysine. Protein modification; protein ubiquitination. Low expression in most tissues. Higher expression in kidney tubular cells. Overexpressed in astrocytoma tumor cells. Belongs to the TRIM/RBCC family.