Differential effects of Alloherpesvirus CyHV-3 and Rhabdovirus SVCV on apoptosis in fish cells

Whilst Herpesviridae, which infect higher vertebrates, actively influence host immune responses to ensure viral replication, it is mostly unknown if Alloherpesviridae, which infect lower vertebrates, possess similar abilities. An important antiviral response is clearance of infected cells via apoptosis, which in mammals influences the outcome of infection. Here, we utilise common carp infected with CyHV-3 to determine the effect on the expression of genes encoding apoptosis-related proteins (p53, Caspase 9, Apaf-1, IAP, iNOS) in the pronephros, spleen and gills. The influence of CyHV-3 on CCB cells was also studied and compared to SVCV (a rhabdovirus) which induces apoptosis in carp cell lines. Although CyHV-3 induced iNOS expression in vivo, significant induction of the genetic apoptosis pathway was only seen in the pronephros. In vitro CyHV-3 did not induce apoptosis or apoptosis-related expression whilst SVCV did stimulate apoptosis. This suggests that CyHV-3 possesses mechanisms similar to herpesviruses of higher vertebrates to inhibit the antiviral apoptotic process

Ictv virus taxonomy profile: <em>Picobirnaviridae</em>

International audiencePicobirnaviridae is a family of viruses with bi-segmented (rarely unsegmented) dsRNA genomes comprising about 4.4 kbp in total, with small, non-enveloped spherical virions. The family includes one genus (Picobirnavirus) grouping three genetic clusters with high sequence variability, two defined by viruses infecting vertebrates and a third with viruses found in invertebrates. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of Picobirnaviridae