TRIM21 Promotes cGAS and RIG-I Sensing of Viral Genomes during Infection by Antibody-Opsonized Virus

• Published in: PLoS pathogens 2015-10, Vol.11 (10), p.e1005253-e1005253
• Main Authors: Watkinson, Ruth E, McEwan, William A, Tam, Jerry C H, Vaysburd, Marina, James, Leo C
• Format: Article
• Language: English
• Subjects: Adenovirus Infections, Human - immunology; Adenoviruses; Analysis; Animals; Cellular signal transduction; Councils; Cytokines; DEAD Box Protein 58; DEAD-box RNA Helicases - physiology; Deoxyribonucleic acid; DNA; Experiments; Gene expression; Genome, Viral; Genomes; Genomics; HeLa Cells; Humans; Immunity, Innate; Immunoglobulin G - immunology; Infections; Influence; Medical research; Mice; Mice, Inbred C57BL; Nucleotidyltransferases - physiology; Pathogens; Pattern recognition; Phagocytosis; Picornaviridae Infections - immunology; Receptors, Immunologic; Rhinovirus; Ribonucleoproteins - physiology; Sensors; Software; Viral infections; Virus Diseases - immunology; Viruses
• ISSN: 1553-7374; 1553-7366; 1553-7374
• DOI: 10.1371/journal.ppat.1005253

Encapsidation is a strategy almost universally employed by viruses to protect their genomes from degradation and from innate immune sensors. We show that TRIM21, which targets antibody-opsonized virions for proteasomal destruction, circumvents this protection, enabling the rapid detection and degradation of viral genomes before their replication. TRIM21 triggers an initial wave of cytokine transcription that is antibody, rather than pathogen, driven. This early response is augmented by a second transcriptional program, determined by the nature of the infecting virus. In this second response, TRIM21-induced exposure of the viral genome promotes sensing of DNA and RNA viruses by cGAS and RIG-I. This mechanism allows early detection of an infection event and drives an inflammatory response in mice within hours of viral challenge.