E3 ubiquitin-protein ligase which regulates the IFN-beta production and antiviral response downstream of various DNA-encoded pattern-recognition receptors (PRRs). Promotes nuclear IRF3 ubiquitination and proteasomal degradation. Bridges together TBK1 and NEMO during the innate response to viral infection leading to the activation of TBK1. 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 TBK1; this interaction bridges together TBK1 and NEMO in order to activate TBK1. Interacts with INCA1. Viral infection mediates TRIM26 nuclear translocation. Autoubiquitinates upon viral infection. In turn, autoubiquitinated TRIM26 recruits NEMO and bridges TBK1-NEMO interaction. Belongs to the TRIM/RBCC family.