Expansible chamber devices
Patent
1996-09-24
1999-03-23
Degen, Nancy
Expansible chamber devices
424 936, 435 691, 4352351, 4353201, A01N 6300, C12N 700, C12N 701, C12N 1579
Patent
active
058855696
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a baculovirus for use as an insect biological control agent, and more particularly to a baculovirus comprising a heterologous gene capable of expressing an insecticidal protein, use of the baculovirus to minimise production of certain viral progeny, and a method of controlling insect pests.
By insect biological control agent we mean an agent which when brought into association with an insect is capable of infecting the insect and interfering with the normal biochemical and physiological processes and leading ultimately to the disablement or death of the insect.
Baculoviruses constitute one of the largest and most diverse groups of insect-pathogenic viruses, and are commonly used as powerful expression systems for heterologous proteins. There is now great interest in baculoviruses as insect biological control agents. In particular, work is being carried out on improving the time the virus takes to kill its host insect by combining the pathogenicity of the baculovirus with the insecticidal action of a toxin, hormone, or enzyme which is active on insects.
A concern over the use of recombinant baculoviruses capable of expressing a heterologous insecticidal gene product to produce enhanced and commercially viable levels of insecticidal activity is that the recombinant baculoviruses might compete with wild-type viruses and hence become established within the environment, even perhaps taking over from the wild-type virus populations. By wild-type baculovirus, we mean a non-recombinant baculovirus. Emphathis is therefore being put on developing recombinant baculoviruses which do not need to persist in the environment to deliver an insecticidal effect.
With the objective of reducing the survival capacity of the recombinant baculoviruses used as insecticides various, more-or-less, complex systems have been proposed. Each of these proposals has potential drawbacks.
For example, Miller at al (Biotechnology for Crop Protection, 1988, Ed. Hedin et al, pp 405) proposed that effective, safe recombinant baculoviruses could be produced by a co-occlusion method. In this method recombinant baculoviruses, which themselves lack the capacity to express the polyhedrin gene necessary for the production of the occlusion bodies required to provide environmental stability, are propagated in mixed infections with wild-type viruses, which provide the polyhedrin protein. Polyhedra containing both recombinant and wild-type virus particles are produced. The idea behind this proposal was that the co-occlusion process would provide a method for delivering a polyhedrin minus (pol.sup.-) baculovirus, i.e. lacks the functional polyhedrin gene, to the field in an infectious form. Persistence of the co-occluded pol.sup.- baculovirus in a virus population is determined by the probability of co-infection of individual larvae and cells with both virus types as the virus is passed from insect to insect.
Limited field trials of the survival characteristics of co-occluded virus populations have been reported by Wood et al (see the general review--Annu. Rev. Microbiol. (1991), 45, p69-87, in particular page 83). Perhaps rather surprisingly the rate of decline of the polyhedrin deficient genomes from the population of baculovirus was found to be slow.
From a production standpoint, preparation of co-occluded virus populations will also be technically demanding, requiring very carefully controlled dual infection methods, and essentially wasteful, as a significant proportion of the product is useless with respect to delivering an improved insecticidal effect.
An alternative approach to the use of genetic manipulation to provide baculovirus populations which are genetically deficient in the ability to make polyhedra is to replicate baculoviruses which lack the functional polyhedra gene in a cell line/host which has been genetically engineered to express the missing polyhedrin. In use the resultant virus particles are active per os, but after propagation the wild-type virus cannot produce polyhedrin or occlusion bodies. The p
REFERENCES:
Ashburner, M., et al., Developmental Genetics, "On the Evolutionary Relationships of Drosophilia melanogaster," 1984, vol. 4, pp. 295-312.
Bonning, B. C., Journal of General Virology, "Superior expression of juvenile hormone esterase and .beta.-galactosidase from the basic protein promoter of Autographa californica nuclear polyhedrosis virus compared to the p10 protein and polyhedrin promotors," 1994, vol. 75, pp. 1551-1556.
Cammue, B.P.A., et al., The Journal of Biological Chemistry, "Isolation and Characterization of a Novel Class of Plant Antimicrobial Peptides from Mirabilis jalapa L. Seeds," 1992, vol. 267(4), pp. 2228-2233.
Eldridge, R., et al., Journal of Virology, "Characterization of a Baculovirus Gene Encoding a Small Conotoxinlike Polypeptide," 1992, vol. 66(11), pp. 6563-6571.
Fainzilber, M., et al., Eur. J. Biochem., "Mollusc-specific toxins from the venom of Conus textile neovicarius," 1991, vol. 202, pp. 589-595.
Hillyard, D.R., et al., Biochemistry, "A Molluscivorous Conus Toxin: Conserved Frameworks in Conotoxins," 1989, vol. 28, pp. 358-361.
Hughes, P.R., et al., Journal of Invertebrate Pathology, "A Synchronoous Peroral Technique for the Bioassay of Insect Viruses," 1981, vol. 37, pp. 154-159.
Ikemura, T., Mol. Biol. Evol., "Codon Usage and tRNA Content in Unicellular and Multicellular Organisms," 1985, vol. 2(1), pp. 13-34.
Kozak, M., J. Mol. Biol., "At Least Six Nucleotides Preceding the AUG Initiator Codon Enhance Translation in Mammalian Cells," 1987, vol. 196, pp. 947-950.
Kozak, M., Cell, "Point Mutations Define a Sequence Flanking the AUG Intiatator Codon That Modulates Translation by Eukaryotic Ribosomes," 1986, vol. 44, pp. 283-292.
Kozak, M., Nucleic Acids Research, "Compilation and analysis of sequences upstream from the translational start site in eukaryotic Mrnas," 1984, vol. 12(2), pp. 857-872.
Kozak, M., Nucleic Acids Research, "Possible role of flanking nucleotides in recognition of the AUG initiator codon by eukaryotic ribosomes," 1981, vol. 19(20), pp. 5233-5252.
McCutchen, B.F., Bio/Technology, "Development of a Recombinant Baculovirus Expressing an Insect-Selective Neurotoxin: Potential for Pest Control," 1991, vol. 9, pp. 848-852.
Miller, D. W., Biotechnology for Crop Protection, "Genetically Engineered Viral Insecticides," 1988, pp. 405-421.
Olivera, B. M., et al., Science, "Diversity of Conus Neuropeptides," 1990, vol. 249, pp. 257-263.
Olivera, B. M., et al., Journal of Biological Chemistry, "Conotoxins", 1991, vol. 266(33), pp. 22067-22070.
Possee, R.D., et al., Nucleic Acids Research, "Analysis of the polyhedrin gene promoter of the Autographa californica nuclear polyhedrosis virus," 1987, vol. 15(24), pp. 10233-10248.
Sharp, P. M., et al., Nucleic Acids Research, "Codon usage in yeast: cluster analysis clearly differentiates highly and lowly expressed genes," 1986, vol. 14(13), pp. 5125-5143.
Stewart, L.M.D, et al., Nature, "Construction of an improved baculovirus insecticide containing an insect-specific toxin gene," 1991, vol. 352, pp. 85-88.
Tomalski, M.D., et al., Bio/Technology, "Expression of a Paralytic Neurotoxin Gene to Improve Insect Baculoviruses as Biopesticides," 1992, vol. 10, pp. 545-549.
Tomalski, M.D., et al., Nature, "Insect paralysis of baculovirus-mediated expression of a mite neurotoxin gene," 1991, vol. 352, pp. 82-85.
von Heijne, G., Nucleic Acids Research, "A new method for predicting signal sequence cleavage sites," 1986, vol. 14(11), pp. 4683-4691.
Wada, K., et al., Nucleic Acids Research, "Codon usage tabulated from the GenBank genetic sequence data," 1991 vol. 20, Supplement, pp. 2111-2118.
Weyer, U., et al., Journal of General Virology, "Analysis of very late gene expression by Autographa californica nuclear polyhedrosis virus and the further development of multiple expression vectors," 1990, vol. 71, pp. 1525-1534.
Wood, H. A., et al., Annu. Rev. Microbiol., "Genetically Engineered Baculoviruses as Agents for Pest Control," 1991, vol. 45, pp. 69-87.
Woodward, S.R., The
Degen Nancy
Thomson Marian T.
Zeneca Limited
LandOfFree
Biological insect control agent does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Biological insect control agent, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Biological insect control agent will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2122536