Flavivirus infection: essential ultrastructural changes and association of Kunjin virus NS3 protein with microtubules.

Virus-induced vesicles evolved early in the Kunjin virus replication cycle around 9 to 10 h p.i. just before the end of the latent period in infected Vero cells. About 2 h following the appearance of the vesicles, microtubule paracrystals were also formed. These two virus-induced structures seemed interlinked and have essential roles in Kunjin virus replication. A viral protein NS3 was found to be associated with the microtubule component of the cells. When vinblastine sulphate was added to the cells immediately after infection, formation of the paracrystals was delayed by two hours, and the affiliation of NS3 protein was also observed to be rearranged.