Bioluminescent and fluorescent reporter-expressing recombinant Akabane virus (AKAV): an excellent tool for analyzing virus replication

Tentatively accepted

Akabane virus (AKAV) is a worldwide epidemic arbovirus of the Bunyavirales group that predominantly infects livestock and causes severe congenital malformations. The reporter-expressing recombinant virus represents a powerful tool for characterizing virus biology in vitro and in vivo. Here we have described the successful establishment of a reverse genetics system for AKAV. The virus obtained had similar growth properties in vitro as the parent virus. In addition, the recombinant AKAV reporter viruses expressing nanoluciferase (Nluc) or mWasabi were constructed by insertion into the S segment and named rAKAV-Nluc and rAKAV-mWasabi, respectively. We then examined the virological properties of rAKAV-Nluc and rAKAV-mWasabi and found that rAKAV-Nluc had similar growth kinetics to the parental virus and could stably produce nano-luciferase even after ten rounds of serial passages. rAKAV-mWasabi also demonstrated comparable growth kinetics and genetic stability to the parent virus. We also used the two reporter viruses to test the susceptibility of different cell lines to AKAV and found that cell lines derived from different host species, including human, pig, bovine, and monkey, efficiently facilitate AKAV replication, furthering our understanding of the AKAV cell tropism range. Overall, our established reverse genetics system for AKAV provides more practical screening tools and can be used to study AKAV virulence and tropism as well as elucidate the molecular biology of AKAV.