CHARACTERIZATION OF JKT-7400, AN ORBIVIRUS WHICH GROWS IN AEDES-ALBOPICTUS MOSQUITO CELLS - EVIDENCE POINTING TO A MINOR VIRION PROTEIN, VP6, AS THE RNA GUANYLYLTRANSFERASE

JKT-7400 virus, an orbivirus originally isolated from Culex mosquitos, was plaque purified and adapted to Aedes albopictus mosquito cells. C onditions which enhance viral cytopathic effect and optimize plaque fo rmation are described. In contrast to bluetongue virus, the prototype orbivirus, no replication of JKT-7400 virus in vertebrate cells was ob served. The core particle of JKT-7400 virus contains 10 segments of ds RNA and three minor proteins, VP1, VP4, and VP6. The inner shell conta ins two major proteins, VP2 and VP7, and the outer shell consists of t he other two major proteins, VP3 and VP5. Evidence is presented sugges ting that the viral protein associated with the capping of virus mRNA, i.e., the guanylyltransferase, is VP6, one of the core proteins. (C) 1997 Academic Press.