E3 ubiquitin ligase that plays a role in several processes including innate immnity, autophagy or inflammation (PubMed:28594402, PubMed:34512673). Negatively regulates miRNAs by modulating the ubiquitination and stability of TNRC6A, a protein involved in RNA-mediated gene silencing by both micro-RNAs (miRNAs) and short interfering RNAs (PubMed:24778252). This ubiquitination results in the suppressed expression of miR-138-5p leading to increased autophagy (PubMed:31160576). Upon enteroviral infection, promotes ‘Lys-63’-mediated ubiquitination activation of IFIH1/MDA5 leading to innate signaling cascade (PubMed:28594402). Mechanistically, selectively recognizes MDA5 filaments that occur on dsRNAs (PubMed:33373584). Plays also a role in limitation of inflammation through different mechanisms. First, promotes ‘Lys-48’-mediated ubiquitination of VCAM1 leading to its degradation and limitation of LPS-induced lung inflammation (PubMed:31310649). In addition, negatively regulates inflammasome activation by promoting ‘lys48’-linked ubiquitination of NLRP3 which is critical for the inhibition of NLRP3 inflammasome activation in resting macrophages (PubMed:34512673).
