RIG-I/MDA5/MAVS are required to signal a protective IFN response in rotavirus-infected intestinal epithelium

• Published in: The Journal of immunology (1950) 2011-02, Vol.186 (3), p.1618-1626
• Main Authors: Broquet, Alexis H, Hirata, Yoshihiro, McAllister, Christopher S, Kagnoff, Martin F
• Format: Article
• Language: English
• Subjects: Adaptor Proteins, Signal Transducing - deficiency; Adaptor Proteins, Signal Transducing - physiology; Animals; Cell Line; Chlorocebus aethiops; DEAD Box Protein 58; DEAD-box RNA Helicases - deficiency; DEAD-box RNA Helicases - physiology; HT29 Cells; Humans; Interferon-beta - biosynthesis; Interferon-beta - physiology; Interferon-Induced Helicase, IFIH1; Intestinal Mucosa - enzymology; Intestinal Mucosa - immunology; Intestinal Mucosa - virology; Membrane Proteins - deficiency; Membrane Proteins - physiology; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Knockout; Nerve Tissue Proteins - deficiency; Nerve Tissue Proteins - physiology; Receptors, Cell Surface; Receptors, Immunologic; Response Elements - immunology; RNA Helicases - genetics; RNA Helicases - physiology; RNA, Viral - biosynthesis; RNA, Viral - genetics; Rotavirus; Rotavirus - genetics; Rotavirus - immunology; Signal Transduction - genetics; Signal Transduction - immunology; Virus Replication - genetics; Virus Replication - immunology
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.1002862

Rotavirus is a dsRNA virus that infects epithelial cells that line the surface of the small intestine. It causes severe diarrheal illness in children and ∼500,000 deaths per year worldwide. We studied the mechanisms by which intestinal epithelial cells (IECs) sense rotavirus infection and signal IFN-β production, and investigated the importance of IFN-β production by IECs for controlling rotavirus production by intestinal epithelium and virus excretion in the feces. In contrast with most RNA viruses, which interact with either retinoic acid-inducible gene I (RIG-I) or melanoma differentiation-associated gene 5 (MDA5) inside cells, rotavirus was sensed by both RIG-I and MDA5, alone and in combination. Rotavirus did not signal IFN-β through either of the dsRNA sensors TLR3 or dsRNA-activated protein kinase (PKR). Silencing RIG-I or MDA5, or their common adaptor protein mitochondrial antiviral signaling protein (MAVS), significantly decreased IFN-β production and increased rotavirus titers in infected IECs. Overexpression of laboratory of genetics and physiology 2, a RIG-I-like receptor that interacts with viral RNA but lacks the caspase activation and recruitment domains required for signaling through MAVS, significantly decreased IFN-β production and increased rotavirus titers in infected IECs. Rotavirus-infected mice lacking MAVS, but not those lacking TLR3, TRIF, or PKR, produced significantly less IFN-β and increased amounts of virus in the intestinal epithelium, and shed increased quantities of virus in the feces. We conclude that RIG-I or MDA5 signaling through MAVS is required for the activation of IFN-β production by rotavirus-infected IECs and has a functionally important role in determining the magnitude of rotavirus replication in the intestinal epithelium.