E3 ubiquitin ligase that catalyzes 'Lys-63'-linked polyubiquitination of target protein, enhancing protein-protein interaction and cell signaling (PubMed:19825828). Transfers ubiquitin from E2 ubiquitin-conjugating enzyme UBE2V1-UBE2N to substrate protein (PubMed:19825828). Essential adapter molecule in IL17A-mediated signaling (PubMed:19825828, PubMed:24120361). Upon IL17A stimulation, interacts with IL17RA and IL17RC receptor chains through SEFIR domains and catalyzes 'Lys-63'-linked polyubiquitination of TRAF6, leading to TRAF6-mediated activation of NF-kappa-B and MAPkinase pathways (PubMed:19825828). 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. Interacts with IKBKG/NF-kappa B essential modulator, with CHUK/IKK-alpha and with IKBKB/IKK-beta (PubMed:12459498). Interacts with TRAF6; this interaction is direct (PubMed:12459498, PubMed:19825828). Interacts with IL17RA and IL17RC (PubMed:19825828, PubMed:24120361, PubMed:33723527). Interacts with IL17RB (PubMed:24120361). Widely expressed. Disease susceptibility is associated with variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The presence of U-box domain is not predicted by SMART and SWISS-MODEL tools. Truncated N-terminus.