Ubiquitin-binding adapter that participates in inflammatory, antiviral and innate immune processes as well as selective autophagy regulation (PubMed:30459273, PubMed:29940186, PubMed:30909570). Plays a key role in the negative regulation of NF-kappa-B and IRF3 signalings by acting as an adapter for the ubiquitin-editing enzyme A20/TNFAIP3 to bind and inactivate its substrates (PubMed:17703191). Disrupts the interactions between the E3 ubiquitin ligase TRAF3 and TBK1/IKBKE to attenuate 'Lys63'-linked polyubiquitination of TBK1 and thereby IFN-beta production (PubMed:21885437). Recruits also A20/TNFAIP3 to ubiquitinated signaling proteins TRAF6 and RIPK1, leading to their deubiquitination and disruption of IL-1 and TNF-induced NF-kappa-B signaling pathways (PubMed:17703191). Inhibits virus-induced apoptosis by inducing the 'Lys-48'-linked polyubiquitination and degradation of MAVS via recruitment of the E3 ligase ITCH, thereby attenuating MAVS-mediated apoptosis signaling (PubMed:27736772). As a macroautophagy/autophagy receptor, facilitates the xenophagic clearance of pathogenic bacteria such as Salmonella typhimurium and Mycobacterium tuberculosis (PubMed:26451915). Upon NBR1 recruitment to the SQSTM1-ubiquitin condensates, acts as the major recruiter of RB1CC1 to these ubiquitin condensates to promote their autophagic degradation (PubMed:33226137, PubMed:34471133). Mediates the autophagic degradation of other substrates including TICAM1 (PubMed:28898289).