NLRX1 Protein Attenuates Inflammatory Responses to Infection by Interfering with the RIG-I-MAVS and TRAF6-NF-kappa B Signaling Pathways

作者：Allen Irving C; Moore Chris B; Schneider Monika; Lei Yu; Davis Beckley K; Scull Margaret A; Gris Denis; Roney Kelly E; Zimmermann Albert G; Bowzard John B; Ranjan Priya; Monroe Kathryn M; Pickles Raymond J; Sambhara Suryaprakash; Ting Jenny P Y^*

来源：Immunity, 2011, 34(6): 854-865.

DOI：10.1016/j.immuni.2011.03.026

The nucleotide-binding domain and leucine-rich-repeat-containing (NLR) proteins regulate innate immunity. Although the positive regulatory impact of NLRs is clear, their inhibitory roles are not well defined. We showed that Nlrx1(-/-) mice exhibited increased expression of antiviral signaling molecules IFN-beta, STAT2, OAS1, and IL-6 after influenza virus infection. Consistent with increased inflammation, Nlrx1(-/-) mice exhibited marked morbidity and histopathology. Infection of these mice with an influenza strain that carries a mutated NS-1 protein, which normally prevents IFN induction by interaction with RNA and the intracellular RNA sensor RIG-I, further exacerbated IL-6 and type 1 IFN signaling. NLRX1 also weakened cytokine responses to the 2009 H1N1 pandemic influenza virus in human cells. Mechanistically, Nlrx1 deletion led to constitutive interaction of MAVS and RIG-I. Additionally, an inhibitory function is identified for NLRX1 during LPS activation of macrophages where the MAVS-RIG-I pathway was not involved. NLRX1 interacts with TRAF6 and inhibits NF-kappa B activation. Thus, NLRX1 functions as a checkpoint of overzealous inflammation.

• 出版日期2011-6-24