SLCR-Sea Lice Research Centre, Department of Biology, University of Bergen, Thormøhlensgt. 55, Pb. 7803, NO-5020, Bergen, Norway.
Sci Rep. 2017 Oct 25;7(1):14030. doi: 10.1038/s41598-017-14282-3.
Rhabdoviruses are a family of enveloped negative-sense single-stranded RNA viruses infecting a variety of hosts. Recently, two vertically transmitted salmon louse (Lepeophtheirus salmonis) rhabdoviruses (LsRV) have been identified. The prevalence of these viruses was measured along the Norwegian coast and found to be close to 100%, and with the present lack of suitable cell lines to propagate these viruses, it is challenging to obtain material to study their host impact and infection routes. Thus, virus free lice strains were established from virus infected lice carrying one or both LsRVs by treating them with N protein dsRNA twice during development. The viral replication of the N protein was specifically down-regulated following introduction of virus-specific dsRNA, and virus-free lice strains were maintained for several generations. A preliminary study on infection routes suggested that the LsRV-No9 is maternally transmitted, and that the virus transmits from males to females horizontally. The ability to produce virus free strains allows for further studies on transmission modes and how these viruses influences on the L.salmonis interaction with its salmonid host. Moreover, this study provides a general fundament for future studies on how vertically transmitted rhabdoviruses influence the biology of their arthropod hosts.
弹状病毒是一类感染多种宿主的有包膜的负义单链 RNA 病毒。最近，已经鉴定出两种垂直传播的鲑虱（Lepeophtheirus salmonis）弹状病毒（LsRV）。这些病毒的流行率沿挪威海岸进行了测量，发现接近 100%，而且由于目前缺乏合适的细胞系来繁殖这些病毒，因此很难获得用于研究其宿主影响和感染途径的材料。因此，通过在发育过程中两次用 N 蛋白 dsRNA 处理携带一种或两种 LsRV 的病毒感染的虱，可以从携带病毒的虱中建立无病毒虱株。引入病毒特异性 dsRNA 后，N 蛋白的病毒复制特异性下调，并且无病毒虱株可以维持数代。对感染途径的初步研究表明，LsRV-No9 是母系传播的，并且病毒从雄性水平传播到雌性。能够产生无病毒株使得可以进一步研究传播方式以及这些病毒如何影响 L.salmonis 与其鲑鱼宿主的相互作用。此外，这项研究为未来研究垂直传播的弹状病毒如何影响其节肢动物宿主的生物学提供了一般性基础。
