Inflammasomes are multi-protein complexes that regulate chronic inflammation-associated diseases by inducing interleukin-1 β (IL-1β) secretion. Numerous components involved in inflammasome activation have been identified, but the mechanisms of inflammasome-mediated IL-1β secretion have not yet been fully explored. Here, we demonstrate that end-binding protein 1 (EB1), which is required for activation of AIM2 inflammasome complex, links the AIM2 inflammasome to autophagy-dependent secretion. Imaging studies revealed that AIM2 inflammasomes colocalize with microtubule organizing centers and autophagosomes. Biochemical analyses showed that poly(dA-dT)-activated AIM2 inflammasomes induce autophagy and IL-1β secretion in an LC3-dependent fashion. Furthermore, depletion of EB1 decreases autophagic shedding and intracellular trafficking. Finally, we found that the 5'-AMP activated protein kinase may regulate this EB1-mediated autophagy-based inflammasome-induced secretion of IL-1β. These findings reveal a novel EB1-mediated pathway for the secretion of IL-1β.
Keywords: AMP-activated Kinase (AMPK); Autophagy; EB1; IL-1b; Inflammasome; Inflammation; Interleukin; Microtubule.
© 2014 by The American Society for Biochemistry and Molecular Biology, Inc.