This characteristic results in a relatively unstable virus. The ambisense genome organization consists of one open reading frame in the viral sense at the 5' end of the molecule and a second open reading frame near the 3' end in the viral complementary sense. A large A-U rich intergenic region separates the two open reading frames. RNA genome segments and may have other functions involved in replication. NSs accumulates to very high concentrations in infected cells, but its function remains a mystery.
Many challenges remain as investigations of Tospoviruses continue.
New viruses in this group continue to be identified. More effective and efficient control strategies are required in almost every group of crops, especially field crops. The genome organization has slowed progress in elucidating fundamental knowledge regarding gene function. At the present time there is still no system for routine reverse genetics for any member of the Bunyaviridae. Tomato Spotted Wilt Virus.