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Characterization of the infection cycle of the Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus in Lymantria dispar cellsBradford, Mary Beth 08 June 1990 (has links)
The Baculoviridae is a family of DNA viruses which are obligate
pathogens for a variety of insects. Baculovirus strains came to the
attention of researchers because they provided a nonchemical
alternative for the biological control of insect pests of agriculture
and forestry (Ignoffo, 1968); however, recently they have been studied
for their potential as vectors for the expression of foreign genes
(Jasny, 1988). Baculoviruses are divided into three subgroups
designated A, B, and C. Subgroup A, the most studied, consists of
nuclear polyhedrosis viruses (NPVs) in which many virions are embedded
in crystals called polyhedra. This group can be further subdivided into
two morphological types (SNPV and MNPV). The SNPV feature single
enveloped nucleocapsids which are occluded, whereas the MNPV contain one
or more nucleocapsids within an envelope which is then occluded.
Subgroup B, known as the granulosis viruses (GVs), occlude single
virions in the crystalline matrix made of the protein granulin.
Subgroup C, the nonoccluded baculoviruses (NOB), do not have an
occlusion body surrounding the virions (for review, see Granados, 1980).
After the initial infection, the virus progeny may exhibit one of
two phenotypes. After encapsidation the virion may leave the nucleus
and acquire an envelope by budding through the host plasma membrane.
This budded form (BV) goes on to infect cells and spread the virus
within the original host. As the infection proceeds with time the viral
DNA can become encapsidated, enveloped and occluded within the nucleus.
This polyhedra-derived virus (PDV) form spreads the infection from
insect to insect.
The following report is a study of the sequence of events that
occur during the infection of Lymantria dispar cells in culture by the
baculovirus Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus
(OpMNPV), each of which was examined at three multiplicities of
infection (5, 10, and 100). During the time course of infection (0
to120 h), DNA was isolated from infected cell lysates and Southern blot
anaylsis demonstrated that viral DNA is first observable at 12-18 h p.i.
for this system. The total production of BV and its rate of production
were measured by titration of infected cell supernatants and both
results show the maximum increase of BV to be during the period of 24-36
h p.i. Light microscopy revealed the presence of polyhedra by 48 h p.i.
Western blot analysis was used to examine the time course of the
expression of the three viral-induced proteins (gp64, p39-capsid, and
polyhedrin) each of which represents a temporal phase of baculovirus
gene expression within the infection cycle. The m.o.i. appeared to have
little effect on the timing of all of the events studied (DNA synthesis,
BV production, PIB detection, and protein synthesis). However, the
magnitude of such events as early DNA synthesis and gp64 expression, and
the later levels of PIB production appeared to correspond to the m.o.i. / Graduation date: 1991
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Quantitative histopathology and epidemiology of prawn viral diseases /Littik, Semuel Ayub Mathias. January 2003 (has links)
Thesis (Ph.D.) -- James Cook University, 2003. / Typescript (photocopy) Bibliography: leaves [149]-164.
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Cis- and trans-acting sequences involved in baculovirus transcription and replicationRasmussen, Charlotte 08 December 1995 (has links)
Graduation date: 1996
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Characterization of Baculovirus genes involved in genome replication and processing /Vanarsdall, Adam L. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 227-245). Also available on the World Wide Web.
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Regulation of expression of four baculovirus genes and the immunocytochemical characterization of their productsGross, Christian Hans 12 May 1992 (has links)
Regulation of expression of three genes in the polyhedron
envelope protein (PEP) gene region of the Orgyia pseudotsugata
multinucleocapsid nuclear polyhedrosis virus (OpMNPV) was
examined. These genes include open reading frame (ORF) 1 (encoding
p21), ORF 2 (encoding gp16), and ORF 3 (encoding the polyhedron
envelope protein). The effect of elimination of the late promoter
elements of each ORF or both ORFs 1 and 2 on ORF 3 expression was
examined by using an ORF 3 promoter-CAT gene fusion. The data
indicated that the ORF 3 promoter was essential for the expression of
the PEP. Destruction of ORF 1 caused no effect whereas destruction of
ORF 2 promoter resulted in a 29% increase in CAT activity.
To characterize the role of ORF 1 and 2 in the viral life cycle and
the location of the proteins in virions and infected cells, antisera were
produced against these proteins. The 21 kDa protein was present in
both purified budded and occluded virions as demonstrated by
Western blot analysis. Immunoelectron microscopy showed that the
21 kDa protein was a capsid-associated protein in both phenotypes.
The ORF 2 gene encodes a 12 kDa protein that is N-glycosylated,
migrates at a MW of 16 kDa, and is not present in budded or occluded
virions. Immunoelectron microscopy indicated that gp16 is associated
with lamellar-like membranous structures in close association with the
nuclear membrane. It was also found associated with envelopes of
virions that had budded from the nucleus into the cytoplasm.
A gene that reportedly has a similar role to ORF 3 (polyhedron
envelope protein) has been described in Autographa californica
MNPV. This gene encodes a protein called the spheroidin-like protein
(SLP) because of its sequence similarity to the spheroidin inclusion
protein of the Choristoneura biennis entomopox virus. The gene was
located, sequenced, transcriptionally mapped in OpMNPV and an
antiserum was produced against a fusion protein containing most of
the SLP ORF. Immunoelectron microscopy showed that the protein
was concentrated in cytoplasmic inclusion bodies and was not
associated with the polyhedron envelope structure in OpMNPV. It was
found to be associated with polyhedra of AcMNPV, but no specific
association with the polyhedron envelope was found.
The role of the PEP and the p10 protein in polyhedron
morphogenesis was examined using deletion mutants of OpMNPV
and immunoelectron microscopy. The p10 deletion mutant produced
polyhedra with patchy and poorly attached polyhedron envelopes,
suggesting p10 has a direct or indirect role in the proper formation of
the polyhedron envelope. The PEP deletion mutant showed that PEP
was an essential component in the formation of the polyhedron
envelope. The mutant with both p10 and PEP deleted had polyhedra
that showed a distinct cubic morphology. These data suggest that these
two proteins may affect polyhedra morphology. / Graduation date: 1993
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A multifaceted study of white spot syndrome virus (WSSV), a shrimp pathogenYou, Zerong. January 2003 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2003. / Includes bibliographical references (leaves 134-148).
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FACTORS AFFECTING BACULOVIRUS HELIOTHIS - INDUCED MORTALITY IN THE TOBACCO BUDWORM, HELIOTHIS VIRESCENS (F.).POTTER, MICHAEL FRED. January 1982 (has links)
Efficacy of Baculovirus heliothis against larvae of the tobacco budworm was studied under laboratory, greenhouse, and field conditions. Dosage-mortality studies using a diet surface inoculation technique resulted in LC₅₀ values of less than 2 PIB/mm² for 1- to 5-day-old larvae. Onset of mortality was delayed in older larvae, and a greater quantity of inoculum was needed to produce the same mortality level as larvae matured. Length of the incubation period was shortened by increasing the dose. In laboratory and greenhouse studies, mortality of neonates was enhanced by the addition of commercial feeding stimulants. A cottonseed-base adjuvant was more effective than either virus alone or virus mixed with soybean flour. The value of the bait was particularly apparent when larvae were held for short durations on virus-treated terminals. Water extracts of fresh and dried garbanzo beans were shown to be highly attractive to tobacco budworm larvae, suggesting their potential for use as a feeding stimulant. Both bean treatments performed as well as the commercial cottonseed adjuvant. Virus-water extracts of garbanzo bean leaves and pods were no more effective in producing larval mortality than virus in water alone. Although addition of a feeding stimulant significantly extended activity of virus residues on cotton terminals bioassayed with H. virescens in the laboratory, the combination did not improve efficacy when larvae were allowed to feed on treated plants in the field. It may be that the effect of bait on young larvae was overridden by high temperatures or light intensities in the upper plant canopy. Time of application studies directed at the egg-stage showed that larvae are capable of ingesting lethal quantities of the pathogen while chewing out of treated eggs. Applications should coincide as closely as possible with egg hatch to maximize infection. Following hatching, there was a consistent decline in effectiveness as treatments were delayed. No significant effects on longevity or fecundity resulted from the feeding of virus to adults in a sucrose solution. Transovum transmission of virus to progeny was inefficient, regardless of the dose administered.
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Characterisation of the ecdysteroid UDP-glucosyltransferase of Autographa californica nucleopolyhedrovirusEvans, Owain Prys January 1998 (has links)
No description available.
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The role of lef-2 in the replication of Autographa californica nuclear polyhedrosis virusHarrold, Claire Louise January 1995 (has links)
No description available.
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Agglutination of vertebrate erythrocytes by the granulosis virus of Plodia interpunctellaAnderson, Dennis Keith January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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