A genome-wide CRISPR/Cas9 knock-out screen identifies the DEAD box RNA helicase DDX42 as a broad antiviral inhibitor

Boris Bonaventure (1) , Antoine Rebendenne (1) , Francisco Garcia de Gracia (1) , Marine Tauziet (1) , Joe Mckellar (1) , Ana Luiza Chaves Valadão (1) , Valérie Courgnaud (2) , Eric Bernard (1) , Laurence Briant (1) , Nathalie Gros (3) , Wassila Djilli (1) , Mary Arnaud-Arnould (1) , Hugues Parrinello (4) , Stéphanie Rialle (4) , Olivier Moncorgé (1) , Caroline Goujon (1)

1 IRIM - Institut de Recherche en Infectiologie de Montpellier
2 IGMM - Institut de Génétique Moléculaire de Montpellier
3 CEMIPAI - Centre d’études des Maladies Infectieuses et Pharmacologie Anti-Infectieuse - [Montpellier]
4 IGF MGX - Institut de Génomique Fonctionnelle - Montpellier GenomiX

Genome-wide CRISPR/Cas9 knock-out genetic screens are powerful approaches to unravel new regulators of viral infections. With the aim of identifying new cellular inhibitors of HIV-1, we have developed a strategy in which we took advantage of the ability of type 1 interferon (IFN) to potently inhibit HIV-1 infection, in order to create a cellular environment hostile to viral replication. This approach led to the identification of the DEAD-box RNA helicase DDX42 as an intrinsic inhibitor of HIV-1. Depletion of endogenous DDX42 using siRNA or CRISPR/Cas9 knock-out increased HIV-1 infection, both in model cell lines and in physiological targets of HIV-1, primary CD4+ T cells and monocyte-derived macrophages (MDMs), and irrespectively of the IFN treatment. Similarly, the overexpression of a dominant-negative mutant of DDX42 positively impacted HIV-1 infection, whereas wild-type DDX42 overexpression potently inhibited HIV-1 infection. The positive impact of endogenous DDX42 depletion on HIV-1 infection was directly correlated to an increase in viral DNA accumulation. Interestingly, proximity ligation assays showed that DDX42, which can be mainly found in the nucleus but is also present in the cytoplasm, was in the close vicinity of HIV-1 Capsid during infection of primary monocyte-derived macrophages. Moreover, we show that DDX42 is also able to substantially decrease infection with other retroviruses and retrotransposition of long interspersed elements-1 (LINE-1). Finally, we reveal that DDX42 potently inhibits other pathogenic viruses, including Chikungunya virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Domaines: Immunité innée; Virologie; Interactions cellulaires [q-bio.CB]

Boris Bonaventure, Antoine Rebendenne, Francisco Garcia de Gracia, Marine Tauziet, Joe Mckellar, et al.. A genome-wide CRISPR/Cas9 knock-out screen identifies the DEAD box RNA helicase DDX42 as a broad antiviral inhibitor. 2020. ⟨hal-03017363⟩