Article

Activation of innate immune antiviral response by NOD2

Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.
Nature Immunology (Impact Factor: 20). 09/2009; 10(10):1073-80. DOI: 10.1038/ni.1782
Source: PubMed

ABSTRACT

Pattern-recognition receptors (PRRs), including Toll-like receptors (TLRs) and RIG-like helicase (RLH) receptors, are involved in innate immune antiviral responses. Here we show that nucleotide-binding oligomerization domain 2 (Nod2) can also function as a cytoplasmic viral PRR by triggering activation of interferon-regulatory factor 3 (IRF3) and production of interferon-beta (IFN-beta). After recognition of a viral ssRNA genome, Nod2 used the adaptor protein MAVS to activate IRF3. Nod2-deficient mice failed to produce interferon efficiently and showed enhanced susceptibility to virus-induced pathogenesis. Thus, the function of Nod2 as a viral PRR highlights the important function of Nod2 in host antiviral defense mechanisms.

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