Canadian Forest Service Publications Exposure of ichnovirus
particles to digitonin leads to enhanced infectivity and induces
fusion from without in an in vitro model system. 2007. Stoltz,
D.; Lapointe, R.; Makkay, A.; Cusson, M. J. Gen. Virol. 88:
2977-2984. Available from: Laurentian Forestry Centre Catalog
ID: 28033 Unlike most viruses, the mature ichnovirus particle
possesses two unit membrane envelopes. Following loss of the
outer membrane in vivo, nucleocapsids are believed to gain entry
into the cytosol via a membrane fusion event involving the inner
membrane and the plasma membrane of susceptible host cells;
accordingly, experimentally induced damage to the outer membrane
might be expected to increase infectivity. Here, in an attempt
to develop an in vitro model system for studying ichnovirus
infection, we show that digitonin-induced disruption of the
virion outer membrane not only increases infectivity, but also
uncovers an activity not previously associated with any
polydnavirus: fusion from without.