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S D Moore - One of the best experts on this subject based on the ideXlab platform.
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genome analysis and genetic stability of the Cryptophlebia leucotreta granulovirus crlegv sa after 15 years of commercial use as a biopesticide
International Journal of Molecular Sciences, 2017Co-Authors: Marcel Van Der Merwe, S D Moore, Caroline Knox, Michael D Jukes, Lukasz Rabalski, John K Opokudebrah, Martyna Krejmerrabalska, Boguslaw Szewczyk, Martin HillAbstract:Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) is an indigenous pest in southern Africa which attacks citrus fruits and other crops. To control T. leucotreta in South Africa, an integrated pest management (IPM) programme incorporating the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV-SA) as a biopesticide has been implemented. This study investigated the genetic stability of a commercially produced CrleGV-SA product that has been applied in the field since 2000. Seven representative full-genome sequences of the CrleGV-SA isolate spanning a 15-year period were generated and compared with one another. Several open reading frames (ORFs) were identified to have acquired single nucleotide polymorphisms (SNPs) during the 15-year period, with three patterns observed and referred to as “stable”, “reversion”, and “unstable switching”. Three insertion events were also identified, two of which occurred within ORFs. Pairwise multiple alignments of these sequences showed an identity ranging from 99.98% to 99.99%. Concentration-response bioassays comparing samples of CrleGV-SA from 2000 and 2015 showed an increase in virulence toward neonate T. leucotreta larvae. The CrleGV-SA genome sequence generated from the 2015 sample was compared to the Cape Verde reference genome, CrleGV-CV3. Several fusion events were identified between ORFs within these genomes. These sequences shared 96.7% pairwise identity, confirming that CrleGV-SA is a genetically distinct isolate. The results of this study indicate that the genome of CrleGV-SA has remained stable over many years, with implications for its continued use as a biopesticide in the field. Furthermore, the study describes the first complete baculovirus genome to be sequenced with the MinION (Oxford Nanopore, Oxford, UK) platform and the first complete genome sequence of the South African CrleGV isolate.
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the Cryptophlebia leucotreta granulovirus 10 years of commercial field use
Viruses, 2015Co-Authors: S D Moore, Wayne Kirkman, Garth I Richards, P R StephenAbstract:In the last 15 years, extensive work on the Cryptophlebia leucotreta granulovirus (CrleGV) has been conducted in South Africa, initially in the laboratory, but subsequently also in the field. This culminated in the registration of the first CrleGV-based biopesticide in 2004 (hence, the 10 years of commercial use in the field) and the second one three years later. Since 2000, more than 50 field trials have been conducted with CrleGV against the false codling moth, Thaumatotibia leucotreta, on citrus in South Africa. In a representative sample of 13 field trials reported over this period, efficacy (measured by reduction in larval infestation of fruit) ranged between 30% and 92%. Efficacy was shown to persist at a level of 70% for up to 17 weeks after application of CrleGV. This only occurred where the virus was applied in blocks rather than to single trees. The addition of molasses substantially and sometimes significantly enhanced efficacy. It was also established that CrleGV should not be applied at less than ~2 × 1013 OBs per ha in order to avoid compromised efficacy. As CrleGV-based products were shown to be at least as effective as chemical alternatives, persistent and compatible with natural enemies, their use is recommended within an integrated program for control of T. leucotreta on citrus and other crops.
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an improved larval diet for commercial mass rearing of the false codling moth thaumatotibia leucotreta meyrick lepidoptera tortricidae
African Entomology, 2014Co-Authors: S D Moore, G I Richards, C Chambers, Don HendryAbstract:False codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera:Tortricidae), is endemic to sub-Saharan Africa (Newton 1998). It is a pest of citrus (Newton 1998), stone fruit (Daiber 1978), macadamias (La Croix & Thindwa 1986), avocados (Erichsen & Schoeman 1992) and various other agricultural crops. All available control methods were recently reviewed by Moore & Hattingh (2012). Included amongst these is the use of granulovirus (Cryptophlebia leucotreta granulovirus (CrleGV)) sprays, inundative releases of egg parasitoids and the sterile insect technique (SIT). All of these require production of large numbers of T. leucotreta. CrleGV and the egg parasitoid, Trichogrammatoidea Cryptophlebiae (Nagaraja) (Hymenoptera: Trichogrammatidae), are produced in vivo (Moore et al. 2011) and for SIT, the sterilized adult male moth is the product (Hofmeyr et al. 2005).
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overcrowding of false codling moth thaumatotibia leucotreta meyrick leads to the isolation of five new Cryptophlebia leucotreta granulovirus crlegv sa isolates
Journal of Invertebrate Pathology, 2013Co-Authors: John K Opokudebrah, Caroline Knox, Martin Hill, S D MooreAbstract:False codling moth, Thaumatotibia leucotreta (Meyrick) is a serious pest of economic importance to the South African fruit industry. As part of sustainable efforts to control this pest, biological control options that involve the application of baculovirus-based biopesticides such as Cryptogran and Cryptex (both formulated with a South African isolate of Cryptophlebia leucotreta granulovirus, CrleGV-SA) are popularly used by farmers. In order to safeguard the integrity of these biopesticides as well as protect against any future development of resistance in the host, we conducted a study to bioprospect for additional CrleGV isolates as alternatives to existing ones. Using overcrowding as an induction method for latent infection, we recovered five new CrleGV isolates (CrleGV-SA Ado, CrleGV-SA Mbl, CrleGV-SA Cit, CrleGV-SA MixC and CrleGV-SA Nels). Single restriction endonuclease (REN) analysis of viral genomic DNA extracted from purified occlusion bodies showed that isolates differed in their DNA profiles. Partial sequencing of granulin and egt genes from the different isolates and multiple alignments of nucleotide sequences revealed the presence of single nucleotide polymorphisms (SNPs), some of which resulted in amino acid substitutions in the protein sequence. Based on these findings as well as comparisons with other documented CrleGV isolates, we propose two phylogenetic groups for CrleGV-SA isolates recovered in this study.
Johannes A Jehle - One of the best experts on this subject based on the ideXlab platform.
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the genome of the Cryptophlebia leucotreta granulovirus
Virology, 2003Co-Authors: Martin Lange, Johannes A JehleAbstract:Abstract The genome of the Cryptophlebia leucotreta granulovirus (CrleGV) was sequenced and analyzed. The double-stranded circular genome contains 110,907 bp and potentially encodes 129 predicted open reading frames (ORFs), 124 of which were similar to other baculovirus ORFs. Five ORFs were CrleGV specific and 26 ORFs were common to other granulovirus genomes. One ORF showed a significant similarity to a nonstructural protein of Bombyx mori densovirus-2. A baculovirus chitinase gene was identified, which is most likely not functional, because its central coding region including the conserved chitinase active site signature is deleted. Three gene copies (Crle20, 23, and 24) containing the Baculo PEP N domain of the polyhedron envelope protein were identified in CrleGV and other GV genomes. One of them (Crle23) appeared also to contain a p10-like sequence encoding of a number of leucine-rich heptad repeats and a proline-rich domain. Another striking feature of the genome is the presence of a hypervariable non- hr ori -like region of about 1800 bp consisting of different kinds of repeats and palindromes. Three other repeat-rich regions were identified within the genome and are considered as homologous regions ( hrs ). CrleGV is most closely related to the Cydia pomonella granulovirus (CpGV) as revealed by genome order comparisons and phylogenetic analyses. However, the AT content of the CrleGV genome, which is 67.6% and the highest found so far in baculoviruses, differed by 12.8% from the AT content of CpGV. This resulted in a major difference in the codon usage of both viruses and may reflect adaptive selection constraints to their particular hosts.
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the expansion of a hypervariable non hr ori like region in the genome of Cryptophlebia leucotreta granulovirus provides in vivo evidence for the utilization of baculovirus non hr oris during replication
Journal of General Virology, 2002Co-Authors: Johannes A JehleAbstract:In this report a naturally occurring hypervariable region within the genome of different Cryptophlebia leucotreta granulovirus genotypes is characterized. The region consists of a stretch of direct repeats, short palindromes and an unusual AT-rich region. Although the organization of these repeat sequences is unique to baculoviruses, it has the structural features of a ‘non-hr’ origin of DNA replication (ori). Restriction analysis and Southern hybridization revealed that this region is expanded during virus replication. Sequence comparison of different isolated genotypes indicated that the expansion is caused by concatenation of short repeats within the region or by concatenation of the complete region. These findings indicate that the expansion of non-hr origin-like regions is not restricted to defective-interfering particles, as was found previously for baculoviruses propagated in cell culture. Moreover, it appears that non-hr complexity contributes to the natural heterogeneity and genetic plasticity of baculovirus genomes. Also, circumstantial evidence is discussed that hr oris might have developed from internal rearrangement and multiplication of a non-hr ori during baculovirus evolution.
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the granulin gene region of Cryptophlebia leucotreta granulosis virus sequence analysis and phylogenetic considerations
Journal of General Virology, 1994Co-Authors: Johannes A Jehle, Horst BackhausAbstract:The nucleotide sequence of a 2.2 kb genome region of the baculovirus Cryptophlebia leucotreta granulosis virus (ClGV) encompassing the granulin gene and a second open reading frame, designated ORF909, was determined. The putative granulin ORF comprises 744 nucleotides encoding a polypeptide with a predicted M r of 29.3K. The 5′ leader of the granulin gene contains a canonical late baculovirus promoter (ATAAG) and differs only in two nucleotide positions from the sequence of Cydia pomonella granulosis virus (CpGV). Sequence comparison with the granulin genes of different granulosis viruses indicated a very close relationship between ClGV and CpGV of about 96% amino acid identity. ORF909 is 909 nucleotides in length and encodes a potential protein of M r 36.2K. It contains two zinc finger-like motifs, similar to ME53, which was previously described for Autographa californica multiple nucleocapsid nuclear polyhedrosis virus. ORF909 protein is significantly shorter than ME53 protein, lacking more than 105 amino acids of the amino terminus of ME53. Both genes contain an early and a late promoter motif suggesting a similar temporal regulation. Homologous sequences to ORF909 are also present upstream of the granulin genes of other granulosis viruses (GVs) indicating that this ORF is common in GVs.
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genome organization of the dna binding protein gene region of Cryptophlebia leucotreta granulosis virus is closely related to that of nuclear polyhedrosis viruses
Journal of General Virology, 1994Co-Authors: Johannes A Jehle, Horst BackhausAbstract:The nucleotide sequence and genomic organization of a conserved genome region within the EcoRI G fragment of Cryptophlebia leucotreta granulosis virus (C1GV) is presented. Five open reading frames (ORFs) were identified which were homologous to those of Autographa californica nuclear polyhedrosis virus (AcMNPV), located upstream of the helicase gene (p143) at 63.6 to 65.6 map units. The ORFs of C1GV and AcMNPV share nucleotide sequence homologies of about 47 to 53% and are very similarly arranged. One of the ClGV ORFs potentially encodes a basic DNA-binding protein with an M r of about 7.3K. Its predicted amino acid sequence mainly consists of multiple arginine and serine residues and shows a 52 to 55% identity to the DNA-binding proteins of AcMNPV and other nuclear polyhedrosis viruses. Its amino acid composition conforms to that of the DNA-binding proteins of Plodia interpunctella granulosis virus and Spodoptera litura granulosis virus.
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physical map of the Cryptophlebia leucotreta granulosis virus genome and its relationship to the genome of cydia pomonella granulosis virus
Journal of General Virology, 1992Co-Authors: Johannes A Jehle, Horst Backhaus, Eva Fritsch, Jiirg HuberAbstract:A physical map of the genome of Cryptophlebia leucotreta granulosis virus (ClGV) was constructed for the restriction enzymes BamHI, EcoRI, KpnI, NdeI, NruI, SacI and XhoI using hybridization techniques. The size of the viral genome was determined to be 112.4 kbp. A restriction fragment library covering almost the entire genome of ClGV was constructed, and the position of the granulin gene was identified by cross-hybridization with granulin coding fragments of Cydia pomonella granulosis virus (CpGV). Two further regions of intergenomic similarity between ClGV and CpGV were mapped. These regions were aligned and show a collinear arrangement.
Martin Hill - One of the best experts on this subject based on the ideXlab platform.
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genome analysis and genetic stability of the Cryptophlebia leucotreta granulovirus crlegv sa after 15 years of commercial use as a biopesticide
International Journal of Molecular Sciences, 2017Co-Authors: Marcel Van Der Merwe, S D Moore, Caroline Knox, Michael D Jukes, Lukasz Rabalski, John K Opokudebrah, Martyna Krejmerrabalska, Boguslaw Szewczyk, Martin HillAbstract:Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) is an indigenous pest in southern Africa which attacks citrus fruits and other crops. To control T. leucotreta in South Africa, an integrated pest management (IPM) programme incorporating the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV-SA) as a biopesticide has been implemented. This study investigated the genetic stability of a commercially produced CrleGV-SA product that has been applied in the field since 2000. Seven representative full-genome sequences of the CrleGV-SA isolate spanning a 15-year period were generated and compared with one another. Several open reading frames (ORFs) were identified to have acquired single nucleotide polymorphisms (SNPs) during the 15-year period, with three patterns observed and referred to as “stable”, “reversion”, and “unstable switching”. Three insertion events were also identified, two of which occurred within ORFs. Pairwise multiple alignments of these sequences showed an identity ranging from 99.98% to 99.99%. Concentration-response bioassays comparing samples of CrleGV-SA from 2000 and 2015 showed an increase in virulence toward neonate T. leucotreta larvae. The CrleGV-SA genome sequence generated from the 2015 sample was compared to the Cape Verde reference genome, CrleGV-CV3. Several fusion events were identified between ORFs within these genomes. These sequences shared 96.7% pairwise identity, confirming that CrleGV-SA is a genetically distinct isolate. The results of this study indicate that the genome of CrleGV-SA has remained stable over many years, with implications for its continued use as a biopesticide in the field. Furthermore, the study describes the first complete baculovirus genome to be sequenced with the MinION (Oxford Nanopore, Oxford, UK) platform and the first complete genome sequence of the South African CrleGV isolate.
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Citrus thrips, Scirtothrips aurantii (Thysanoptera: Thripidae), damage and infestation in the presence of molasses
Crop Protection, 2015Co-Authors: Sean R. Thackeray, Sean D. Moore, Matthew C. Parkinson, Martin HillAbstract:Abstract The Cryptophlebia leucotreta granulovirus (CrleGV) is used for control of false codling moth (FCM), Thaumatotibia leucotreta (Lepidoptera: Tortricidae), on citrus in South Africa. The virus is applied with molasses, which has been shown to improve its efficacy against FCM. However, little is known about the influence of molasses used as a spray additive on citrus thrips, Scirtothrips aurantii , a major cosmetic pest of citrus fruit. The aim of this study was to determine if molasses influences the occurrence of, and damage to fruit, caused by Scitothrips aurantii . A field trial was conducted that included trees sprayed with different molasses concentrations and control trees at four sites in the Eastern Cape Province of South Africa. Scirtothrips aurantii population sizes were quantified through monitoring with yellow sticky traps, a scouting protocol and a damage assessment after application of the respective treatments. Numbers of adult S. aurantii caught with yellow sticky traps were high for all study sites but there was no significant difference among treatments within sites (P > 0.05). Scouting also revealed high S. aurantii numbers combined with low numbers of predatory mites. However, there was no significant difference in the number of adult or larval S. aurantii present on fruit among treatments within sites (P > 0.05). A damage evaluation, conducted one month after the study, showed no significant difference among treatments (P > 0.05). This study has shown that the inclusion of molasses, applied as a medium cover spray, does not result in increased S. aurantii infestation or damage and can thus be included in the CrleGV applications.
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Comparison of the Biology of Geographically Distinct Populations of the Citrus Pest, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), in South Africa
African Entomology, 2014Co-Authors: John K. Opoku-debrah, Caroline Knox, Martin Hill, Sean D. MooreAbstract:Baculovirus biopesticides are an important component of integrated pest management programmes worldwide. One such example is the Cryptophlebia leucotreta granulovirus (CrleGV) which is used for the control of false codling moth, Thaumatotibia (= Cryptophlebia) leucotreta (Meyrick) (Lepidoptera: Tortricidae), a pest of citrus and other crops in South Africa. A potential problem associated with constant application of viral biopesticides is the differing susceptibility to the virus observed between different geographic populations of the insect host. This could be related to a number of factors, including biological performance and fitness of the target insect population. This study compared a variety of phenotypic traits between geographically distinct T. leucotreta populations collected from the Addo, Marble Hall, Citrusdal and Nelspruit regions of South Africa, and reared under laboratory conditions for several generations. Traits including pupal mass, female fecundity, egg hatch, pupal survival, adult eclosion and developmental time were used as parameters to measure biological performance and fitness. Insects from the Citrusdal region of the Western Cape exhibited significantly lower pupal mass, female fecundity, egg hatch, pupal survival, adult eclosion and the longest duration in larval and pupal development compared to the other colonies investigated. This is the first study to report differences in the performance of laboratory reared T. leucotreta from different geographic locations, and the findings may have important implications for the application of viral biopesticides for the control of this pest in South Africa.
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overcrowding of false codling moth thaumatotibia leucotreta meyrick leads to the isolation of five new Cryptophlebia leucotreta granulovirus crlegv sa isolates
Journal of Invertebrate Pathology, 2013Co-Authors: John K Opokudebrah, Caroline Knox, Martin Hill, S D MooreAbstract:False codling moth, Thaumatotibia leucotreta (Meyrick) is a serious pest of economic importance to the South African fruit industry. As part of sustainable efforts to control this pest, biological control options that involve the application of baculovirus-based biopesticides such as Cryptogran and Cryptex (both formulated with a South African isolate of Cryptophlebia leucotreta granulovirus, CrleGV-SA) are popularly used by farmers. In order to safeguard the integrity of these biopesticides as well as protect against any future development of resistance in the host, we conducted a study to bioprospect for additional CrleGV isolates as alternatives to existing ones. Using overcrowding as an induction method for latent infection, we recovered five new CrleGV isolates (CrleGV-SA Ado, CrleGV-SA Mbl, CrleGV-SA Cit, CrleGV-SA MixC and CrleGV-SA Nels). Single restriction endonuclease (REN) analysis of viral genomic DNA extracted from purified occlusion bodies showed that isolates differed in their DNA profiles. Partial sequencing of granulin and egt genes from the different isolates and multiple alignments of nucleotide sequences revealed the presence of single nucleotide polymorphisms (SNPs), some of which resulted in amino acid substitutions in the protein sequence. Based on these findings as well as comparisons with other documented CrleGV isolates, we propose two phylogenetic groups for CrleGV-SA isolates recovered in this study.
Caroline Knox - One of the best experts on this subject based on the ideXlab platform.
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genome analysis and genetic stability of the Cryptophlebia leucotreta granulovirus crlegv sa after 15 years of commercial use as a biopesticide
International Journal of Molecular Sciences, 2017Co-Authors: Marcel Van Der Merwe, S D Moore, Caroline Knox, Michael D Jukes, Lukasz Rabalski, John K Opokudebrah, Martyna Krejmerrabalska, Boguslaw Szewczyk, Martin HillAbstract:Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) is an indigenous pest in southern Africa which attacks citrus fruits and other crops. To control T. leucotreta in South Africa, an integrated pest management (IPM) programme incorporating the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV-SA) as a biopesticide has been implemented. This study investigated the genetic stability of a commercially produced CrleGV-SA product that has been applied in the field since 2000. Seven representative full-genome sequences of the CrleGV-SA isolate spanning a 15-year period were generated and compared with one another. Several open reading frames (ORFs) were identified to have acquired single nucleotide polymorphisms (SNPs) during the 15-year period, with three patterns observed and referred to as “stable”, “reversion”, and “unstable switching”. Three insertion events were also identified, two of which occurred within ORFs. Pairwise multiple alignments of these sequences showed an identity ranging from 99.98% to 99.99%. Concentration-response bioassays comparing samples of CrleGV-SA from 2000 and 2015 showed an increase in virulence toward neonate T. leucotreta larvae. The CrleGV-SA genome sequence generated from the 2015 sample was compared to the Cape Verde reference genome, CrleGV-CV3. Several fusion events were identified between ORFs within these genomes. These sequences shared 96.7% pairwise identity, confirming that CrleGV-SA is a genetically distinct isolate. The results of this study indicate that the genome of CrleGV-SA has remained stable over many years, with implications for its continued use as a biopesticide in the field. Furthermore, the study describes the first complete baculovirus genome to be sequenced with the MinION (Oxford Nanopore, Oxford, UK) platform and the first complete genome sequence of the South African CrleGV isolate.
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Heterogeneity in virulence relationships between Cryptophlebia leucotreta granulovirus isolates and geographically distinct host populations: lessons from codling moth resistance to CpGV-M
BioControl, 2016Co-Authors: John K. Opoku-debrah, Martin P. Hill, Caroline Knox, Sean D. MooreAbstract:In South Africa, the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV) is used to control the citrus pest Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae). However, the risk associated with continuous application of a single active ingredient is resistance. In order to manage resistance should it occur in field populations of T. leucotreta in South Africa, five new CrleGV genotypes from geographically distinct insect populations which were shown to exhibit some degree of phenotypic variation were recovered and genetically characterized. In droplet bioassays using seven CrleGV isolates against five T. leucotreta populations, some isolates were found to show higher virulence to some host populations than others. There were marked differences in the LD50 values of isolates and the number of occlusion bodies required per larva ranged between 0.79 and 3.12. The significance of these findings with respect to the application of CrleGV biopesticides and the management of resistance is discussed.
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Comparison of the Biology of Geographically Distinct Populations of the Citrus Pest, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), in South Africa
African Entomology, 2014Co-Authors: John K. Opoku-debrah, Caroline Knox, Martin Hill, Sean D. MooreAbstract:Baculovirus biopesticides are an important component of integrated pest management programmes worldwide. One such example is the Cryptophlebia leucotreta granulovirus (CrleGV) which is used for the control of false codling moth, Thaumatotibia (= Cryptophlebia) leucotreta (Meyrick) (Lepidoptera: Tortricidae), a pest of citrus and other crops in South Africa. A potential problem associated with constant application of viral biopesticides is the differing susceptibility to the virus observed between different geographic populations of the insect host. This could be related to a number of factors, including biological performance and fitness of the target insect population. This study compared a variety of phenotypic traits between geographically distinct T. leucotreta populations collected from the Addo, Marble Hall, Citrusdal and Nelspruit regions of South Africa, and reared under laboratory conditions for several generations. Traits including pupal mass, female fecundity, egg hatch, pupal survival, adult eclosion and developmental time were used as parameters to measure biological performance and fitness. Insects from the Citrusdal region of the Western Cape exhibited significantly lower pupal mass, female fecundity, egg hatch, pupal survival, adult eclosion and the longest duration in larval and pupal development compared to the other colonies investigated. This is the first study to report differences in the performance of laboratory reared T. leucotreta from different geographic locations, and the findings may have important implications for the application of viral biopesticides for the control of this pest in South Africa.
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overcrowding of false codling moth thaumatotibia leucotreta meyrick leads to the isolation of five new Cryptophlebia leucotreta granulovirus crlegv sa isolates
Journal of Invertebrate Pathology, 2013Co-Authors: John K Opokudebrah, Caroline Knox, Martin Hill, S D MooreAbstract:False codling moth, Thaumatotibia leucotreta (Meyrick) is a serious pest of economic importance to the South African fruit industry. As part of sustainable efforts to control this pest, biological control options that involve the application of baculovirus-based biopesticides such as Cryptogran and Cryptex (both formulated with a South African isolate of Cryptophlebia leucotreta granulovirus, CrleGV-SA) are popularly used by farmers. In order to safeguard the integrity of these biopesticides as well as protect against any future development of resistance in the host, we conducted a study to bioprospect for additional CrleGV isolates as alternatives to existing ones. Using overcrowding as an induction method for latent infection, we recovered five new CrleGV isolates (CrleGV-SA Ado, CrleGV-SA Mbl, CrleGV-SA Cit, CrleGV-SA MixC and CrleGV-SA Nels). Single restriction endonuclease (REN) analysis of viral genomic DNA extracted from purified occlusion bodies showed that isolates differed in their DNA profiles. Partial sequencing of granulin and egt genes from the different isolates and multiple alignments of nucleotide sequences revealed the presence of single nucleotide polymorphisms (SNPs), some of which resulted in amino acid substitutions in the protein sequence. Based on these findings as well as comparisons with other documented CrleGV isolates, we propose two phylogenetic groups for CrleGV-SA isolates recovered in this study.
Horst Backhaus - One of the best experts on this subject based on the ideXlab platform.
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TCl4.7: a novel lepidopteran transposon found in Cydia pomonella granulosis virus.
Virology, 1995Co-Authors: Johannes Jehle, J. Huber, Eva Fritsch, Antje Nickel, Horst BackhausAbstract:Abstract After the co-infection of larvae of the lepidopteran Cryptophlebia leucotreta with the two baculoviruses C. leucotreta granulosis virus and Cydia pomonella granulosis virus (ClGV and CpGV, respectively), three CpGV mutants and one ClGV mutant carrying insertions of 0.9 to 4.7 kb have been isolated. By cloning, sequencing, and hybridization analysis, one of these insertions was identified as a transposon-like element derived from the C. leucotreta genome. This element, called TCl4.7, was found in the genome of CpGV which naturally replicates in C. pomonella . Sequence analysis suggested that TCl4.7 is 4726 bp in size, flanked by imperfect inverted terminal repeats of 29 bp, and integrated into the target dinucleotide TA. TCl47 encompasses an open reading frame sharing homologies to transposase genes of the Tc1-related transposable elements found in Caenorhabditis and in Drosophila species. The open reading frame might represent a pseudogene since it is missing an ATG start codon. The integration site of TCl4.7 is located in a non-protein-coding region of the CpGV genome at m.u. 9.5. In bioassays the TCl4.7-carrying virus and all the other mutants except for one showed LC 50 values similar to those of CpGV and ClGV. This is the first report of the horizontal escape of a transposable element during the in vivo infection of lepidopteran larvae by granulosis viruses.
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the granulin gene region of Cryptophlebia leucotreta granulosis virus sequence analysis and phylogenetic considerations
Journal of General Virology, 1994Co-Authors: Johannes A Jehle, Horst BackhausAbstract:The nucleotide sequence of a 2.2 kb genome region of the baculovirus Cryptophlebia leucotreta granulosis virus (ClGV) encompassing the granulin gene and a second open reading frame, designated ORF909, was determined. The putative granulin ORF comprises 744 nucleotides encoding a polypeptide with a predicted M r of 29.3K. The 5′ leader of the granulin gene contains a canonical late baculovirus promoter (ATAAG) and differs only in two nucleotide positions from the sequence of Cydia pomonella granulosis virus (CpGV). Sequence comparison with the granulin genes of different granulosis viruses indicated a very close relationship between ClGV and CpGV of about 96% amino acid identity. ORF909 is 909 nucleotides in length and encodes a potential protein of M r 36.2K. It contains two zinc finger-like motifs, similar to ME53, which was previously described for Autographa californica multiple nucleocapsid nuclear polyhedrosis virus. ORF909 protein is significantly shorter than ME53 protein, lacking more than 105 amino acids of the amino terminus of ME53. Both genes contain an early and a late promoter motif suggesting a similar temporal regulation. Homologous sequences to ORF909 are also present upstream of the granulin genes of other granulosis viruses (GVs) indicating that this ORF is common in GVs.
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genome organization of the dna binding protein gene region of Cryptophlebia leucotreta granulosis virus is closely related to that of nuclear polyhedrosis viruses
Journal of General Virology, 1994Co-Authors: Johannes A Jehle, Horst BackhausAbstract:The nucleotide sequence and genomic organization of a conserved genome region within the EcoRI G fragment of Cryptophlebia leucotreta granulosis virus (C1GV) is presented. Five open reading frames (ORFs) were identified which were homologous to those of Autographa californica nuclear polyhedrosis virus (AcMNPV), located upstream of the helicase gene (p143) at 63.6 to 65.6 map units. The ORFs of C1GV and AcMNPV share nucleotide sequence homologies of about 47 to 53% and are very similarly arranged. One of the ClGV ORFs potentially encodes a basic DNA-binding protein with an M r of about 7.3K. Its predicted amino acid sequence mainly consists of multiple arginine and serine residues and shows a 52 to 55% identity to the DNA-binding proteins of AcMNPV and other nuclear polyhedrosis viruses. Its amino acid composition conforms to that of the DNA-binding proteins of Plodia interpunctella granulosis virus and Spodoptera litura granulosis virus.
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physical map of the Cryptophlebia leucotreta granulosis virus genome and its relationship to the genome of cydia pomonella granulosis virus
Journal of General Virology, 1992Co-Authors: Johannes A Jehle, Horst Backhaus, Eva Fritsch, Jiirg HuberAbstract:A physical map of the genome of Cryptophlebia leucotreta granulosis virus (ClGV) was constructed for the restriction enzymes BamHI, EcoRI, KpnI, NdeI, NruI, SacI and XhoI using hybridization techniques. The size of the viral genome was determined to be 112.4 kbp. A restriction fragment library covering almost the entire genome of ClGV was constructed, and the position of the granulin gene was identified by cross-hybridization with granulin coding fragments of Cydia pomonella granulosis virus (CpGV). Two further regions of intergenomic similarity between ClGV and CpGV were mapped. These regions were aligned and show a collinear arrangement.