Selective autophagy of RIPosomes maintains innate immune homeostasis during bacterial infection

作者：Subhash Mehto, Kautilya Kumar Jena, Rina Yadav, Swatismita Priyadarsini, Pallavi Samal, Sivaram Krishna, Kollori Dhar, Ashish Jain, Nishant Ranjan Chauhan, Krushna Chandra Murmu, Ramyasingh Bal, Rinku Sahu, Pundrik Jaiswal, Bhabani Sankar Sahoo, Srinivas Patnaik, Thomas A. Kufer, Tor Erik Rusten, Swati Chauhan, Swati Chauhan, Punit Prasad, Santosh Chauhan, Santosh Chauhan · 发表于：The EMBO Journal · 年份：2022 · DOI：10.15252/embj.2022111289 · 被引用次数：26 · 研究领域：Autophagy in Disease and Therapy、Inflammasome and immune disorders、Immune cells in cancer

The NOD1/2-RIPK2 is a key cytosolic signaling complex that activates NF-κB pro-inflammatory response against invading pathogens. However, uncontrolled NF-κB signaling can cause tissue damage leading to chronic diseases. The mechanisms by which the NODs-RIPK2-NF-κB innate immune axis is activated and resolved remain poorly understood. Here, we demonstrate that bacterial infection induces the formation of endogenous RIPK2 oligomers (RIPosomes) that are self-assembling entities that coat the bacteria to induce NF-κB response. Next, we show that autophagy proteins IRGM and p62/SQSTM1 physically interact with NOD1/2, RIPK2 and RIPosomes to promote their selective autophagy and limit NF-κB activation. IRGM suppresses RIPK2-dependent pro-inflammatory programs induced by Shigella and Salmonella. Consistently, the therapeutic inhibition of RIPK2 ameliorates Shigella infection- and DSS-induced gut inflammation in Irgm1 KO mice. This study identifies a unique mechanism where the innate immune proteins and autophagy machinery are recruited together to the bacteria for defense as well as for maintaining immune homeostasis.