|
Click here for browse from name or title index
>>
the trans- Golgi vesicles; most of all
newly formed virus particles remain inside the RER-derived
cell vesicles or inside lysosomes, even during cell
lysis. Groups of larger particles, 65-75 nm in diameter
at dengue-2 infections, persist during cell passage.
The large amounts of smooth membrane structures, as
vesicles or tubules inside the RER, are attributed to
a cell response to viral infection
Barth, O. M., L. M. D. Cortes, et
al. (1994). "Ultrastructural aspects of virus replication
in one fatal case and several other isolates from a
dengue type 2 outbreak in Rio de Janeiro." Mem.Inst.Oswaldo.Cruz.
(Rio de Janeiro) 89: 21-24.
OM Barth, Inst Oswaldo Cruz, Dept Virol, AV Brasil 4365,
BR- 21045900 Rio Janeiro, Brazil Dengue virus replication
in mosquito cell cultures was observed by electron microscopy
in one fatal and 40 classical isolates from a dengue
type 2 outbreak in Rio de Janeiro and compared with
the prototype New Guinea C strain. All the Br azilian
isolates presented beside the classical structured dengue
virus particles, fuzzy coated virus-like particles,
never observed in the referencial New Guinea C virus
strain. More numerous DEN- 2 virus particles, fuzzy
coated virus-like particles, defective virus particles
and smooth membrane structures inside the rough endoplasmic
reticulum characterized the unique fatal isolate examined
Barth, O. M., L. M. Cortes, et al.
(1996). "Ultrastructural aspects of the replication
of dengue virus type 2 isolated in Brazil." Mem.Inst.Oswaldo.Cruz.
(Rio de Janeiro) 91: 255-256.
Bartholomeusz, A. I. and P. J. Wright
(1993). "Synthesis of Dengue Virus RNA Invitro
- Initiation and the Involvement of Proteins NS3 and
NS5." Arch.Virol. 128: 111-121.
An assay for flavivirus RNA-dependent RNA polymerase
activity in vitro was established using extracts of
Vero cells infected with dengue virus type 2 (DEN-2)
or Kunjin virus (KUN). RNA synthesis was initiated on
a template of viral replicative form (RF) and RF was
converted to the replicative intermediate (RI). The
RNA- dependent RNA polymerase complex of DEN-2 utilised
either DEN-2 or KUN RF as template, and similarly the
KUN polymerase complex utilised either DEN-2 or KUN
RF template. In addition, antibodies against the nonstructural
proteins NS3 and NS5 inhibited the conversion of RF
to RI, indicating that NS3 and NS5 are involved in viral
RNA replication
Bartholomeusz, A., E. Tomlinson,
et al. (1994). "Use of a flavivirus RNA-dependent
RNA polymerase assay to investigate the antiviral activity
of selected compounds." Antiviral Res. 24: 341-350.
A Bartholomeusz, Fairfield Hosp, Macfarlane Burnet Ctr,
Yarra Bend Rd, Fairfield, Vic 3078, Australia We have
developed an assay using flavivirus RNA- dependent RNA
polymerase to test the inhibitory activity of potential
antiviral agents. The effects of antiviral agents on
RNA. synthesis were examined in this assay using extracts
of Vero cells infected with dengue virus type 2 or Kunjin
virus. Several different classes of known polymerase
inhibitors were tested. The synthesis of double- stranded
replicative form RNA was inhibited in a dose-dependent
fashion in the presence of the polyoxometalate HPA-23
[(NH4)(18)(NaW21Sb9O86)(17)].14 H2O and several
 
|