FIG. 9.

J1R protein is required for DNA packaging in IV formation during vaccinia virion morphogenesis. Schematic drawing of the stages of vaccinia virus morphogenesis, including crescent formation, IV formation, and IMV formation. IMV could be enveloped to become IEV. J1R protein is not required for crescent formation; instead, it plays a role in DNA packaging in IV formation. Also shown are several other viral proteins (A10L, A14L, A17L, A30L, and D13L) in which a mutation interferes with virion morphogenesis before or during the formation of IV (20, 45, 47, 48, 59, 63, 79, 82). CEV, cell-associated virions; EEV, extracellular enveloped viruses.