Susceptibility and Permissivity of Zebrafish (Danio rerio) Larvae to Cypriniviruses

Abstract

The zebrafish (Danio rerio) represents an increasingly important model organism in virology. We evaluated its utility in the study of economically important viruses from the genus Cyprinivirus (anguillid herpesvirus 1, cyprinid herpesvirus 2 and cyprinid herpesvirus 3 (CyHV-3)). This revealed that zebrafish larvae were not susceptible to these viruses after immersion in contaminated water, but that infections could be established using artificial infection models in vitro (zebrafish cell lines) and in vivo (microinjection of larvae). However, infections were transient, with rapid viral clearance associated with apoptosis-like death of infected cells. Transcriptomic analysis of CyHV-3-infected larvae revealed upregulation of interferon-stimulated genes, in particular those encoding nucleic acid sensors, mediators of programmed cell death and related genes. It was notable that uncharacterized non-coding RNA genes and retrotransposons were also among those most upregulated. CRISPR/Cas9 knockout of the zebrafish gene encoding protein kinase R (PKR) and a related gene encoding a protein kinase containing Z-DNA binding domains (PKZ) had no impact on CyHV-3 clearance in larvae. Our study strongly supports the importance of innate immunity-virus interactions in the adaptation of cypriniviruses to their natural hosts. It also highlights the potential of the CyHV-3-zebrafish model, versus the CyHV-3-carp model, for study of these interactions.

In Vivo Imaging Sheds Light on the Susceptibility and Permissivity of Carassius auratus to Cyprinid Herpesvirus 2 According to Developmental Stage

“…In a similar manner, this novel CyHV-2 recombinant also represents a potentially valuable research tool for our future investigations with CyHV-2 and may also be of interest to the wider research community. Furthermore, in parallel to this present study, this novel CyHV-2 recombinant was also successfully utilized in zebrafish infectivity studies [ 45 ], demonstrating its immediate utility in other CyHV-2 related research.…”

“…This experimental procedure was adapted from previous methodology used with zebrafish larvae [ 43 , 44 , 45 ]. Briefly, larvae were infected or mock-infected with the CyHV-2 LucGFP strain by immersion as described previously.…”

In Search of a Target Gene for a Desirable Phenotype in Aquaculture: Genome Editing of Cyprinidae and Salmonidae Species

“…The targets of studies include lysosomes [170,171], endoplasmic reticulum [172], membranes [173], membrane channels [174], cytoskeleton [175], recombination processes [176], aneuploidy [177], expression regulation [178], and signaling [179]. There is research on the genetic basis of the organism's response to oxidative stress [180][181][182][183][184], hypoxia [185][186][187], sodium ion uptake from the surrounding aquatic environment and ammonia excretion [188][189][190], inflammation processes [191,192], immunity [193][194][195][196] and disease resistance [197][198][199][200][201].…”