ADAR-Editing during Ostreid Herpesvirus 1 Infection in Crassostrea gigas : Facts and Limitations

• Published in: mSphere
• Main Authors: Rosani, Umberto, Bortoletto, Enrico, Montagnani, C., Venier, Paola
• Other Authors: Università degli Studi di Padova = University of Padua (Unipd), Interactions Hôtes-Pathogènes-Environnements (IHPE), Université de Perpignan Via Domitia (UPVD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2022
• Subjects: ADAR1; hyper-editing; oyster; OsHV-1; antiviral immunity; ADAR; RNA editing; bivalve; innate immunity; malacoherpesvirus; [SDV.BA.MVSA]Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health; [SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology; Crassostrea gigas
• Online Access: https://hal.science/hal-03636839; https://hal.science/hal-03636839v1/document; https://hal.science/hal-03636839v1/file/Rosani-2022-MSphere-ADAR.pdf; https://doi.org/10.1128/msphere.00011-22

International audience Ostreid herpesvirus-1 (OsHV-1) RNAs are enzymatically modified by A-to-I conversions during the infection of Crassostrea gigas. The increase of ADAR1 expression and hyper-editing activity parallel to OsHV-1 RNAs suggests a functional connection between dsRNA editing and antiviral responses. We analyzed 87 RNA-seq data sets from immuno-primed, resistant, and susceptible oysters exposed to OsHV-1 to compare the ADAR hyper-editing levels on host and viral transcripts and trace hyper-editing on the oyster genes. Host RNAs were more hyper-edited than viral RNAs, despite the increased editing of viral RNAs in late infection phases. A set of genes, representing ∼0.5% of the oyster transcriptome and including several tripartite motif-containing sequences, were constantly hyper-edited. Conversely, we identified genes involved in antiviral response, miRNA maturation, and epigenetic regulation that were hyper-edited in specific conditions only. Despite technical and biological bottlenecks that hamper the understanding of the bivalve “RNA editome,” available tools and technologies can be adapted to bivalve mollusks