title: Efficient Co-Replication of Defective Novirhabdovirus.
abstract: We have generated defective Viral Hemorrhagic Septicemia Viruses (VHSV) which express either the green fluorescent protein (GFP) or a far-red fluorescent protein (mKate) by replacing the genes encoding the nucleoprotein N or the polymerase-associated P protein. To recover viable defective viruses, rVHSV-ΔN-Red and rVHSV-ΔP-Green, fish cells were co-transfected with both deleted cDNA VHSV genomes, together with plasmids expressing N, P and L of the RNA-dependent RNA polymerase. After one passage of the transfected cell supernatant, red and green cell foci were observed. Viral titer reached 10⁷ PFU/mL after three passages. Infected cells were always red and green with the very rare event of single red or green cell foci appearing. To clarify our understanding of how such defective viruses could be so efficiently propagated, we investigated whether (i) a recombination event between both defective genomes had occurred, (ii) whether both genomes were co-encapsidated in a single viral particle, and (iii) whether both defective viruses were always replicated together through a complementation phenomenon or even as conglomerate. To address these hypotheses, genome and viral particles have been fully characterized and, thus, allowing us to conclude that rVHSV-ΔN-Red and rVHSV-ΔP-Green are independent viral particles which could propagate only by simultaneously infecting the same cells.
authors.affiliation: VIM, INRA, Université Paris-Saclay, Jouy-en-Josas 78350, France. ronan.rouxel@jouy.inra.fr.
authors.forename: Ronan N
authors.initials: RN
authors.lastname: Rouxel
authors.affiliation: VIM, INRA, Université Paris-Saclay, Jouy-en-Josas 78350, France. emilie.merour@jouy.inra.fr.
authors.forename: Emilie
authors.initials: E
authors.lastname: Mérour
authors.affiliation: VIM, INRA, Université Paris-Saclay, Jouy-en-Josas 78350, France. stephane.biacchesi@jouy.inra.fr.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Biacchesi
authors.affiliation: VIM, INRA, Université Paris-Saclay, Jouy-en-Josas 78350, France. michel.bremont@jouy.inra.fr.
authors.forename: Michel
authors.initials: M
authors.lastname: Brémont
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003673:Defective Viruses / Q000235:genetics / Q000502:physiology*; D005399:Fishes; D017353:Gene Deletion; D017930:Genes, Reporter / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D008164:Luminescent Proteins / Q000032:analysis / Q000235:genetics; D029141:Novirhabdovirus / Q000235:genetics / Q000502:physiology*; D010957:Plasmids; D012692:Serial Passage; D013194:Staining and Labeling; D019562:Viral Load; D010948:Viral Plaque Assay; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication; D000097573:Red Fluorescent Protein
chemical_list: D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D014764:Viral Proteins; D000097573:Red Fluorescent Protein
keywords: Novirhabdovirus; defective particles; fluorescent proteins