MITD1 is a brain-specific interferon-inducible factor that inhibits flavivirus replication
Abstract
West Nile virus (WNV) and Usutu virus (USUV) are closely related mosquito-borne neurotropic flaviviruses that share common transmission cycle and can infect humans. However, while human infections by WNV are widespread, infections by USUV are comparatively less frequent, less severe, and currently limited to Africa and Europe. To identify human host factors that contribute to the pathogenic signatures of these two flaviviruses, we carried out an arrayed expression screen of over 1,300 interferon-stimulated genes (ISGs). Several ISGs known to target flaviviruses, including IFI6, SHFL, and RTP4 were among the strongest hits. Interestingly, we also found MITD1, an ISG with no previously reported antiviral activity, among the strongest hits. We demonstrated that the antiviral activity of MITD1 was not limited to USUV and WNV, since it also inhibited Zika and dengue virus replication. We found MITD1 to interfere with viral RNA replication by sequestering specific endosomal sorting complexes required for transport-III (ESCRT-III) proteins involved in the formation of viral replication factories. MITD1 expression was not increased by type I interferon (IFN-I) in most human cells and mouse tissues that we examined, although WNV and USUV replication was strongly inhibited by IFN-I. Strikingly, MITD1 was induced in the brain of USUV-infected mice and importantly, in human monocyte-derived microglia. Using human microglial-like cells, we confirmed that MITD1 is an essential mediator of the anti-flavivirus activity of IFN-I in these cells. We conclude that MITD1 plays a key role in the cellular defenses against neurotropic flaviviruses.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (16)
Jim Zoladek
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier
Marion Cannac
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier
Maël Seite
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier
Emma Davies
Medical Research Council-University of Glasgow Centre for Virus Research
Jordan Quellec
Pathogenesis and Control of Chronic and Emerging Infections, INSERM, Établissement français du sang (EFS), Université de Montpellier
Jonathan Barthelemy
Pathogenesis and Control of Chronic and Emerging Infections, INSERM, Établissement français du sang (EFS), Université de Montpellier
Kamila Gorna
UMR Virologie, Laboratoire de Santé Animale, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Anses, Ecole Nationale Vétérinaire d’Alfort
Sophie Desgraupes
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier
Ines Bribes
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier
Sara Salinas
Pathogenesis and Control of Chronic and Emerging Infections, INSERM, Établissement français du sang (EFS), Université de Montpellier
Muriel Coulpier
UMR Virologie, Laboratoire de Santé Animale, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Anses, Ecole Nationale Vétérinaire d’Alfort
Nathalie J. Arhel
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier
Massimo Palmarini
Medical Research Council-University of Glasgow Centre for Virus Research
Yannick Simonin
Pathogenesis and Control of Chronic and Emerging Infections, INSERM, Établissement français du sang (EFS), Université de Montpellier
Sam J. Wilson
Medical Research Council-University of Glasgow Centre for Virus Research
Sébastien Nisole
Viral Trafficking, Restriction and Innate Signaling, CNRS UMR 9004, Institut de Recherche en Infectiologie de Montpellier, Université de Montpellier