Author Correction: WDR77 inhibits prion-like aggregation of MAVS to limit antiviral innate immune response.
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ABSTRACT:
SUBMITTER: Li J
PROVIDER: S-EPMC10520012 | biostudies-literature | 2023 Sep
REPOSITORIES: biostudies-literature
Publications
Author Correction: WDR77 inhibits prion-like aggregation of MAVS to limit antiviral innate immune response.
Li Jiaxin J Zhang Rui R Wang Changwan C Zhu Junyan J Ren Miao M Jiang Yingbo Y Hou Xianteng X Du Yangting Y Wu Qing Q Qi Shishi S Li Lin L Chen She S Yang Hui H Hou Fajian F
Nature communications 20230925 1
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Project description:In response to viral infection, RIG-I-like RNA helicases bind to viral RNA and activate the mitochondrial protein MAVS, which in turn activates the transcription factors IRF3 and NF-?B to induce type I interferons. [corrected] We have previously shown that RIG-I binds to unanchored lysine-63 (K63) polyubiquitin chains and that this binding is important for MAVS activation; however, the mechanism underlying MAVS activation is not understood. Here, we show that viral infection induces the formation of very large MAVS aggregates, which potently activate IRF3 in the cytosol. We find that a fraction of recombinant MAVS protein forms fibrils that are capable of activating IRF3. Remarkably, the MAVS fibrils behave like prions and effectively convert endogenous MAVS into functional aggregates. We also show that, in the presence of K63 ubiquitin chains, RIG-I catalyzes the conversion of MAVS on the mitochondrial membrane to prion-like aggregates. These results suggest that a prion-like conformational switch of MAVS activates and propagates the antiviral signaling cascade.
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