Spodoptera frugiperda cells infected with Autographa californica nucleopolyhedrovirus (AcMNPV) lacking a functional anti-apoptotic p35 protein undergo apoptosis. However, such mutants replicate normally in Trichoplusia ni (TN-368) cells. An AcMNPV plaque isolate (AcdefrT) was identified during propagation of a virus deficient in p35 in TN-368 cells. This virus exhibited enhanced budded-particle formation in TN-368 cells, but was partially defective for polyhedra production in the same cells. Virus replication in AcdefrT-infected TN-368 cells was accompanied by extensive plasma-membrane blebbing and caspase activation late in infection, both features of apoptosis. Rescue of the p35 locus of AcdefrT continued to result in a reduction in polyhedra and increase in budded virus production in TN-368 cells, but no plasma-membrane blebbing was observed. The mutation was mapped to the FP-25 gene locus. This gene mutation combined with the non-functional p35 was found to be responsible for the cell-blebbing effect observed in AcdefrT-infected TN-368 cells.
AyresM. D.,
HowardS. C.,
KuzioJ.,
Lopez-FerberM.,
PosseeR. D.1994; The complete DNA sequence of Autographa californica nuclear polyhedrosis virus. Virology 202:586–605[CrossRef]
BeamesB.,
SummersM. D.1988; Comparison of host cell DNA insertions and altered transcription at the site of insertions in few polyhedra baculovirus mutants. Virology 162:206–220[CrossRef]
BeamesB.,
SummersM. D.1989; Location and nucleotide sequence of the 25K protein missing from baculovirus few polyhedra (FP) mutants. Virology 168:344–353[CrossRef]
BischoffD. S.,
SlavicekJ. M.1997; Phenotypic and genetic analysis of Lymantria dispar nucleopolyhedrovirus few polyhedra mutants: mutations in the 25K FP gene may be caused by DNA replication errors. J Virol 71:1097–1106
ChakrabortyS.,
ReidS.1999; Serial passage of a Helicoverpa armigera nucleopolyhedrovirus in Helicoverpa zea cell cultures. J Invertebr Pathol 73:303–308[CrossRef]
ClemR. J.,
FechheimerM.,
MillerL. K.1991; Prevention of apoptosis by a baculovirus gene during infection of insect cells. Science 254:1388–1390[CrossRef]
ClemR. J.,
RobsonM.,
MillerL. K.1994; Influence of infection route on the infectivity of baculovirus mutants lacking the apoptosis-inhibiting gene p35 and the adjacent gene p94
. J Virol 68:6759–6762
FraserM. J.,
SmithG. E.,
SummersM. D.1983; Acquisition of host cell DNA sequences by baculoviruses: relationship between host DNA insertions and FP mutants of Autographa californica and Galleria mellonella nuclear polyhedrosis viruses. J Virol 47:287–300
GriffithsC. M.,
BarnettA. L.,
AyresM. D.,
WindassJ.,
KingL. A.,
PosseeR. D.1999; In vitro host range of Autographa californica nucleopolyhedrovirus recombinants lacking functional p35 , iap1 or iap2
. J Gen Virol 80:1055–1066
HarrisonR. L.,
SummersM. D.1995; Mutations in the Autographa californica multinucleocapsid nuclear polyhedrosis virus 25 kDa protein gene result in reduced virion occlusion, altered intranuclear envelopment and enhanced virus production. J Gen Virol 76:1451–1459[CrossRef]
HershbergerP. A.,
DicksonJ. A.,
FriesenP. D.1992; Site-specific mutagenesis of the 35-kilodalton protein gene encoded by Autographa californica nuclear polyhedrosis virus: cell line-specific effects on virus replication. J Virol 66:5525–5533
HinkF. W.,
VailP. V.1973; A plaque assay for titration of alfalfa looper nuclear polyhedrosis virus in a cabbage looper (TN-368) cell line. J Invertebr Pathol 22:168–174[CrossRef]
LuaL. H. L.,
PedriniM. R. S.,
ReidS.,
RobertsonA.,
TribeD. E.2002; Phenotypic and genotypic analysis of Helicoverpa armigera nucleopolyhedrosis serially passaged in cell culture. J Gen Virol 83:945–955
PotterK. N.,
FaulknerP.,
MacKinnonE. A.1976; Strain selection during serial passage of Trichoplusia ni nuclear polyhedrosis virus. J Virol 18:1040–1050
RamoskaW. A.,
HinkW. F.1974; Electron microscopic examination of two plaque variants from a nuclear polyhedrosis virus of the alfalfa looper, Autographa californica
. J Invertebr Pathol 23:197–201[CrossRef]
SlavicekJ. M.,
Hayes-PlazollesN.,
KellyM. E.1995; Rapid formation of few polyhedra mutants of Lymantria dispar multinucleocapsid nuclear polyhedrosis virus during serial passage in cell culture. Biol Control 5:251–261[CrossRef]
WoodH. A.1980; Isolation and replication of an occlusion body-deficient mutant of the Autographa californica nuclear polyhedrosis virus. Virology 105:338–344[CrossRef]