Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 151
Filtrar
Mais filtros










Filtros aplicados

Base de dados
Intervalo de ano de publicação
1.
Viruses ; 11(4)2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970670

RESUMO

Virus infections of insects can easily stay undetected, neither showing typical signs of a disease, nor being lethal. Such a stable and most of the time covert infection with Phthorimaea operculella granulovirus (PhopGV) was detected in a Phthorimaea operculella laboratory colony, which originated from Italy (Phop-IT). This covert virus (named PhopGV-R) was isolated, purified and characterized at the genetic level by full genome sequencing. Furthermore, the insect colony Phop-IT was used to study the crowding effect, double infection with other PhopGV isolates (CR3 and GR1), and co-infection exclusion. An infection with a second homologous virus (PhopGV-CR3) activated the covert virus, while a co-infection with another virus isolate (PhopGV-GR1) led to its suppression. This study shows that stable virus infections can be common for insect populations and have an impact on population dynamics because they can suppress or enable co-infection with another virus isolate of the same species.


Assuntos
Animais de Laboratório/virologia , Granulovirus/crescimento & desenvolvimento , Granulovirus/isolamento & purificação , Lepidópteros/virologia , Animais , Animais de Laboratório/crescimento & desenvolvimento , Comportamento Animal , Granulovirus/classificação , Granulovirus/genética , Itália , Lepidópteros/crescimento & desenvolvimento , Dinâmica Populacional , Sequenciamento Completo do Genoma
2.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 4): 233-238, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30950823

RESUMO

Many viral genomes encode kinase and phosphatase enzymes to manipulate pathways that are controlled by phosphorylation events. The majority of viral phosphatase genes occur in the Baculoviridae and Poxviridae families of large DNA viruses. The corresponding protein sequences belong to four major homology groups, and structures are currently available for only two of these. Here, the first structure from the third group, the protein tyrosine phosphatase-2 (PTP-2) class of viral phosphatases, is described. It is shown that Cydia pomonella granulovirus PTP-2 has the same general fold and active-site architecture as described previously for other phosphatases, in the absence of significant sequence homology. Additionally, it has a novel C-terminal extension in an area corresponding to the interface of dimeric poxvirus phosphatases belonging to the Tyr-Ser protein phosphatase homology group.


Assuntos
Granulovirus/enzimologia , Proteína Fosfatase 2/química , Sequência de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Proteínas Quinases/química , Estrutura Secundária de Proteína , Alinhamento de Sequência
3.
Toxins (Basel) ; 11(3)2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30836616

RESUMO

The Cydia pomonella granulovirus (CpGV) GP37 has synergistic effects on the infectivity of nucleopolyhedroviruses (NPVs), however, the mechanism employed is unclear. In this study, in vitro and in vivo binding assays indicated that GP37 efficiently bound to the midgut peritrophic membrane (PM) of Spodoptera exigua larvae. Treatment with GP37 led to the damage of the PM's compacted structure and the generation of the PM perforations, and the enhancement of the PM's permeability. qPCR results further demonstrated that GP37 increased the ability of occlusion-derived virions (ODV) to cross the PM. R18-labeling experiments exhibited that GP37 also promoted the fusion of ODVs and insect midgut epithelia. Altogether, our present results revealed that the synergistic mechanism of GP37 to the infectivity of NPV might involve two parts. GP37 damaged the integrity of the PM after binding, which enhanced the PM's permeability and increased the ability of ODVs to cross the PM, finally facilitating the ODVs reaching the midgut. In addition, GP37 promoted the fusion of ODVs and insect midgut epithelia. Our data expand the understanding of the mechanism used by baculovirus synergistic factors and provide a foundation for the development of high-efficiency baculoviral insecticides.


Assuntos
Granulovirus , Mucosa Intestinal/metabolismo , Corpos de Oclusão Virais/metabolismo , Proteínas Virais/metabolismo , Animais , Membrana Celular/metabolismo , Larva , Spodoptera , Proteínas Virais/genética
4.
Viruses ; 11(2)2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30699913

RESUMO

Baculoviridae is a highly diverse family of rod-shaped viruses with double-stranded DNA. To date, almost 100 species have had their complete genomic sequences deposited in the GenBank database, a quarter of which comprises granuloviruses (GVs). Many of the genomes are sequenced using next-generation sequencing, which is currently considered the best method for characterizing new species, but it is time-consuming and expensive. Baculoviruses form a safe alternative to overused chemical pesticides and therefore there is a constant need for identifying new species that can be active components of novel biological insecticides. In this study, we have described a fast and reliable method for the detection of new and differentiation of previously analyzed granulovirus species based on a real-time polymerase chain reaction (PCR) technique with melting point curve analysis. The sequences of highly conserved baculovirus genes, such as granulin and late expression factors 8 and 9 (lef-8 and lef-9), derived from GVs available to date have been analyzed and used for degenerate primer design. The developed method was tested on a representative group of eight betabaculoviruses with comparisons of melting temperatures to allow for quick and preliminary granulovirus detection. The proposed real-time PCR procedure may be a very useful tool as an easily accessible screening method in a majority of laboratories.


Assuntos
Genoma Viral , Granulovirus/classificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas Virais/genética , Animais , Primers do DNA/genética , DNA Viral/genética , Lepidópteros/virologia , Fases de Leitura Aberta , Análise de Sequência de DNA , Temperatura de Transição
5.
J Gen Virol ; 100(4): 679-690, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30794120

RESUMO

Twelve complete genome sequences of Phthorimaea operculella granulovirus (PhopGV) isolates from four different continents (Africa, South America, Asia and Europe) were analysed after Illumina next-generation sequencing (NGS). The isolates have a circular double-stranded DNA genome that is 118 355 to 119 177 bp in length and all of them encode 130 open reading frames (ORFs). Analysis of single-nucleotide polymorphisms (SNPs) revealed a unique set of SNP positions for every tested isolate. The genome sequences of the investigated PhopGV isolates were classified into a new system of four (1-4) groups according to the presence of group-specific SNPs as well as insertions and deletions. These genome groups correlated with phylogenetic lineages inferred from minimum-evolution trees of the whole-genome consensus nucleotide sequences. All members of group 3 originated from the Mediterranean area, whereas the geographical origin and the group assignment did not correlate for isolates belonging to genome groups 1, 2 or 4. The high degree of coverage facilitated the determination of variant nucleotide frequencies. We conclude that the geographical isolates of PhopGV are genetically highly similar. On the other hand, they were rarely genetically homogenous and in most cases appeared to be mixtures of multiple genotypes.


Assuntos
Granulovirus/genética , Lepidópteros/virologia , Mariposas/virologia , Polimorfismo de Nucleotídeo Único/genética , África , Animais , Ásia , DNA Viral/genética , Europa (Continente) , Genoma Viral/genética , Genótipo , Larva/virologia , Fases de Leitura Aberta/genética , Filogenia , Análise de Sequência de DNA/métodos , América do Sul
6.
J Gen Virol ; 100(4): 709-720, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30775960

RESUMO

Grapevine red blotch virus (GRBV) is type member of the newly identified genus Grablovirus. It possesses a single-stranded circular DNA genome of around 3200 nucleotides encoding three open reading frames (ORFs) in both the virion sense, the V1 (CP), V2 and V3, and complementary sense, C1 (RepA), C2 and C3. As shown for members of the genus Mastrevirus, the C1 and C2 ORFs are predicted to fuse through splicing to form a replication-associated protein (Rep). Data obtained using high-throughput sequencing (RNA-Seq) of three RNA-enriched populations, extracted from GRBV-infected grapevine (Vitis vinifera), confirmed the presence of the predicted C1-C2 intron (nts 2288-2450), but in addition identified a larger virion-sense intron (nts 251-589) spanning the V2 ORF. Evidence for both introns in a number of isolates was supported by bioinformatic analysis of publicly available datasets (n=20). These observations were further supported by RT-PCR analyses in both GRBV-infected grapevine and transient expression assays where GRBV genome segments were agro-inoculated onto Nicotiana benthamiana. The donor site of the virion-sense intron is located within two small ORFs, V0 and V02, while the acceptor site is two-thirds along the V2 ORF. Splicing at these positions is predicted to delete the N terminus of the encoded V2 protein. Comparative analyses of full-length GRBV sequences and the related tentative grabloviruses Prunus geminivirus A and wild Vitis virus 1 support the existence of both introns and V0. The probable regulatory role of these introns in the GRBV infection cycle is discussed.


Assuntos
Granulovirus/genética , Fases de Leitura Aberta/genética , Processamento de RNA/genética , Sequência de Aminoácidos , Sequência de Bases , Geminiviridae/genética , Genoma Viral/genética , Doenças das Plantas/virologia , Vírion/genética , Vitis/virologia
7.
Rev Argent Microbiol ; 51(4): 381-385, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30795935

RESUMO

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an important maize pest. Due to the environmental impact and emergence of resistance caused by chemical pesticides and transgenic events, the use of baculoviruses becomes a safe and useful alternative for its control in integrated pest management strategies. Here we report the identification of a novel isolate of a granulovirus of S. frugiperda native to the central region of Argentina, named SfGV ARG. We observed that larvae infected with SfGV ARG showed a yellowish coloration, swollen body and, in some cases, severe lesions in the last abdominal segments. We confirmed the identity of the isolate by sequencing fragments of the lef-8, lef-9 and granulin genes and by calculating evolutionary distances using the Kimura-2-Parameter model. SfGV ARG DNA restriction pattern allowed to estimate a genome of at least 135 kb.


Assuntos
Granulovirus/classificação , Granulovirus/isolamento & purificação , Spodoptera/virologia , Animais , Argentina
8.
J Invertebr Pathol ; 160: 76-86, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30550745

RESUMO

An antagonistic effect of a microsporidium (Nosema sp.) infection on the virulence of Phthorimaea operculella granulovirus (PhopGV) was recorded in potato tuber moth (Phthorimaea operculella) larvae with mixed infections. When the P. operculella colony was infected at a high rate (42.8-100%) with the microsporidium, it was less susceptible to the isolate PhopGV-GR1.1. A virus concentration 1.89 × 105 higher was necessary to cause the same level of mortality produced in the P. operculella colony when it was uninfected or had a low level of infection with the microsporidium (0-30%). This antagonistic effect was driven by a Nosema isolate (termed Nosema sp. Phop) that was purified from microsporidian-infected P. operculella individuals. The purified microsporidium was characterised by morphological features, including size, filament coils and different developmental stages using transmission electron microscopy (TEM). On the molecular level, the partial cistron rDNA information of the small ribosomal subunit (SSU), internal transcribed spacer (ITS), and the large ribosomal subunit (LSU) were identified. Phylogenetic analyses revealed that the newly described microsporidium belongs to the "true Nosema" clade. Partial sequence information of the RNA polymerase II largest subunit (RPB1) suggested that Nosema bombycis is the closest relative (98% identity). The morphological and phylogenetic characteristics suggest that it is an isolate of N. bombycis. Interactions of microsporidia and betabaculoviruses are rarely described in the literature, although mixed infections of different pathogens seem to be rather common events, ranging from antagonistic to mutualistic interactions. The observed antagonistic relationship between the Nosema sp. and PhopGV-GR1.1 showed that pathogen interactions need to be considered when single pathogens are applied to insect populations in the context of biological control of insect pests.


Assuntos
Coinfecção , Granulovirus/patogenicidade , Mariposas/parasitologia , Mariposas/virologia , Nosema , Animais , Antibiose , Coinfecção/parasitologia , Coinfecção/virologia , DNA Ribossômico/genética , Larva/parasitologia , Larva/virologia , Nosema/classificação , Nosema/genética , Nosema/ultraestrutura , Filogenia
9.
Arch Virol ; 164(3): 839-845, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30506470

RESUMO

DNA polymerase (DNApol) is highly conserved in all baculoviruses and plays an essential role in viral DNA replication. Previous results showed that the DNApol of the betabaculovirus Pieris rapae granulovirus (PiraGV) can localize in the nucleus. However, it is not clear how the DNApol is transported into the nucleus. Bioinformatic and GFP localization analysis showed that PiraGV DNApol contains a nuclear localization signal (NLS) at aa 4-25 (LFKRKLDEPPTDHTLVKAIKLS) of the N-terminus that does not match either the classical monopartite or the bipartite NLS consensus sequence. Multiple-point-substitution analysis confirmed that the NLS is required for transport of PiraGV DNApol into the nucleus. We also substituted the NLS of the PiraGV DNApol for that of the alphabaculovirus Spodoptera litura nuclear polyhedrosis virus (SpltNPV) DNApol. A viral growth curve and quantitative real-time PCR revealed that the substitution impaired viral DNA replication and resulted in a reduction in virus production. Together, our results show that PiraGV contains a novel NLS and that the NLS cannot efficiently replace that of SpltNPV DNApol for viral DNA synthesis and virus production.


Assuntos
DNA Polimerase Dirigida por DNA/química , Granulovirus/enzimologia , Sinais de Localização Nuclear , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Borboletas/virologia , Núcleo Celular/virologia , DNA Viral/genética , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Granulovirus/química , Granulovirus/classificação , Granulovirus/genética , Dados de Sequência Molecular , Análise de Sequência de DNA , Proteínas Virais/química , Proteínas Virais/metabolismo
10.
PLoS One ; 13(8): e0202598, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30133523

RESUMO

A new isolate of the Spodoptera frugiperda granulovirus, SfGV ARG, was completely sequenced and analyzed. The SfGV ARG genome is 139,812 bp long and encodes 151 putative open reading frames. Of these ORFs, 56 were found in betabaculoviruses, 19 of which are present only in GVs closely related to SfGV. Seven ORFs found homologs in this small GV group and also in noctuid NPVs. ORF066 codes a 74 amino acid protein, overlapped with nudix gene, with several homologs in baculovirus, found by tblastn search. Comparison with the genome of the Colombian isolate SfGV VG008 resulted in SfGV being 1101 bp smaller and lacking a homologue of VG008 ORF084, which codes for Lef-7. However, we found that ORF051 shows remote homology to Lef-7 proteins. Moreover, analysis of ORF051 along with Lef-7 proteins coded by a group of noctuid specific GVs and NPVs indicated that Lef-7 proteins coded by these viruses include three F-box domains in contrast to the single one reported for AcMNPV Lef-7. SfGV ARG genome also contains a split photolyase as a distinct feature not found in VG008. BlastX analysis revealed that a complete photolyase is coded considering a putative frameshift in a poly-A tract, which resembles known slippery sequences involved in programmed ribosome frameshifting.


Assuntos
Genômica , Granulovirus/genética , Spodoptera/genética , Proteínas Virais/genética , Sequência de Aminoácidos/genética , Animais , Baculoviridae/genética , Proteínas F-Box/genética , Genoma Viral/genética , Fases de Leitura Aberta/genética , Filogenia , Análise de Sequência de DNA , Spodoptera/virologia
11.
J Agric Food Chem ; 66(31): 8253-8261, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30052037

RESUMO

A series of novel ß-carboline derivatives was designed by combining the anti-tobacco mosaic virus (TMV) lead compound tetrahydro-ß-carboline ester with the hydantoin, thiohydantoin, and urea motifs. These derivatives were synthesized from tetrahydro-ß-carboline ester via a structural diversity-oriented synthesis in one step, and their biological activities were evaluated. Most of the derivatives exhibited anti-TMV activity higher than that of commercial plant virucide ribavirin, such as compounds 2, 4, 5, 7, 9, 15, 16, 19, and 21. Compared with the lead compounds, some of these derivatives showed good insecticidal activity against Plutella xylostella and Culex pipiens pallens. At the same time, these derivatives also showed broad-spectrum fungicidal activity. The systematic study provides strong evidence that the hydantoin, thiohydantoin, and urea motifs of these molecules can improve and modulate the activities of the analogues of natural products.


Assuntos
Carbolinas/síntese química , Carbolinas/farmacologia , Hidantoínas/análise , Praguicidas/síntese química , Tioidantoínas/análise , Ureia/análise , Animais , Antivirais/química , Produtos Biológicos/química , Carbolinas/química , Culex/efeitos dos fármacos , Desenho de Fármacos , Fungicidas Industriais/síntese química , Granulovirus/efeitos dos fármacos , Inseticidas/síntese química , Estrutura Molecular , Vírus do Mosaico do Tabaco/efeitos dos fármacos
12.
J Invertebr Pathol ; 154: 58-64, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29608919

RESUMO

A granulovirus (GV) that produces occlusion bodies (OBs) having an unusual morphology was found in an Adoxophyes sp. (Lepidoptera: Tortricidae) larva in a tea field in Miyazaki Prefecture, Japan. This isolate is considered to be a mutant of Adoxophyes orana granulovirus, designated AdorGV-M, because the nucleotide sequence of its genome is 99.7% identical to that of an English isolate of AdorGV, AdorGV-E. AdorGV-E produces typical ovocylindrical OBs that contain one occlusion-derived virus (ODV) per OB. On the other hand, AdorGV-M produces large cuboidal OBs, but the number of ODVs per OB was unknown. In this study, we quantified viral DNA in OBs of both AdorGV-E and -M, and determined the number of ODVs occluded in an OB of AdorGV-M. The two isolates had the same quantity of viral DNA in each OB, and we thus confirmed that one OB of AdorGV-M contains one ODV. To investigate the process of OB formation, fat body tissue of A. honmai larvae inoculated with each isolate was observed in a time course by transmission electron microscopy, and OB sizes were measured from micrographs. The main difference in OB formation was that AdorGV-M required more time to mature than AdorGV-E. In AdorGV-E, ODVs began to be covered from one end with an ovocylindrical OB at 96 h post-inoculation (hpi), and most of them were completely occluded at 120 hpi. Occlusion of AdorGV-M ODVs also began at 96 hpi, but the OB shape was cuboidal. Moreover, the OB size of AdorGV-M was similar to that of AdorGV-E at 120 hpi, but continued to grow until 192 hpi. AdorGV-M thus took more time to complete OB formation. Consequently, AdorGV-E has mature OBs with a diameter 0.22 µm and length 0.39 µm, but those of AdorGV-M are 1.34 × 1.23 µm.


Assuntos
Granulovirus/fisiologia , Mariposas/virologia , Animais , DNA Viral/química , Granulovirus/genética , Granulovirus/ultraestrutura , Mariposas/ultraestrutura
13.
J Virol Methods ; 256: 107-110, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29571679

RESUMO

Enumeration techniques were compared for quantification of the South African isolate of Cryptophlebia leucotreta granulovirus (CrleGV-SA), used as a biopesticide to control false codling moth (Thaumatotibia leucotreta), an insect pest of various fruits and nuts, including citrus. The routine enumeration method for CrleGV-SA virus particles in experimentation and production of CrleGV-SA biopesticides is dark field microscopy. This method was compared with spectrophotometry, scanning electron microscopy (SEM) and real time quantitative polymerase chain reaction (qPCR). The purpose was to develop an accurate and reliable routine enumeration method for CrleGV-SA occlusion bodies (OBs) and to validate the use of dark field microscopy. Purified and semi-purified CrleGV-SA viral stocks were used. Spectrophotometry was not a suitable or accurate enumeration method. Dark field microscopy and SEM were accurate and statistically comparable (p = 0.064), validating the use of dark field microscopy as an enumeration method for granulovirus (GV). However, SEM has superior resolution and the advantage of easily distinguishing virus particles from debris in semi-purified viral stock preparations. A quantitative PCR technique has been developed based on use of specific oligonucleotide primers for the granulin gene. This has the advantage of not being affected by contamination with non-biological debris or biological material, which impact on the other methods.


Assuntos
Vírus de Insetos/genética , Vírus de Insetos/ultraestrutura , Viroses/virologia , DNA Viral , Genoma Viral , Granulovirus/genética , Granulovirus/ultraestrutura , Microscopia , Reação em Cadeia da Polimerase em Tempo Real , Espectrofotometria
14.
J Virol ; 92(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29563284

RESUMO

Autographa californica multiple nucleopolyhedrovirus (AcMNPV) DNA polymerase (DNApol) plays a crucial role in viral DNA synthesis, and the N terminus (residues 1 to 186) is highly conserved in the baculovirus DNApol family. However, the functional role of the N terminus of DNApol has not yet been characterized. Here we report a functional analysis of the AcMNPV DNApol N terminus. We truncated the DNApol N terminus to construct truncation mutants Bac-GFP-PolΔ64, Bac-GFP-PolΔ110, and Bac-GFP-PolΔ186, which lack 64, 110, and 186 N-terminal residues, respectively. Although the truncation mutants rescued viral DNA synthesis and infectious virus production, the level of DNA replication decreased, and Bac-GFP-PolΔ64, Bac-GFP-PolΔ110, and Bac-GFP-PolΔ186 showed 10-fold, 89-fold, and 891-fold reductions in infectious viral yield compared to that of the wild-type repair virus, respectively. Production of occlusion bodies was compromised for all truncation mutants. Further bioinformatic analysis showed that the first 64 amino acids (aa) at the extreme N terminus contains a conserved α(-helix)-ß(-sheet)-ß-ß secondary-structure region, and further downstream sequence from aa 67 to 186 is comprised of four conserved sequence motifs. Multiple alanine point substitutions in the α-ß-ß-ß structure region or the four sequence motifs in the N terminus impaired viral DNA replication and resulted in reduction of virus yield and occlusion body production. Together, our results suggested that the secondary structure and four conserved motifs within the N terminus of AcMNPV DNApol are important for viral DNA synthesis, infectious virus yield, and production of occlusion bodies.IMPORTANCE DNA polymerase (DNApol) is highly conserved in all baculoviruses and is required for viral DNA replication. The N terminus is one of the highly conserved regions of baculovirus DNApols. Our results showed that the N terminus of baculovirus DNA polymerase plays an important role in efficient viral DNA synthesis and infectious virus yield and production of occlusion bodies. We identified five features, including a highly conserved secondary structure and four conserved amino acid motifs, in the AcMNPV DNApol N terminus, all of which are important for efficient viral DNA synthesis, infectious virus yield, and production of occlusion bodies.


Assuntos
Replicação do DNA/genética , DNA Viral/genética , DNA Polimerase Dirigida por DNA/genética , Nucleopoliedrovírus/genética , Spodoptera/genética , Sequência de Aminoácidos/genética , Animais , Linhagem Celular , Granulovirus/genética , Conformação de Ácido Nucleico , Estrutura Secundária de Proteína/genética , Células Sf9 , Replicação Viral/genética
15.
J Invertebr Pathol ; 151: 7-13, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29079531

RESUMO

Both Agrotis segetum nucleopolyhedrovirus B (AgseNPV-B) and Agrotis segetum granulovirus (AgseGV) belong to a cluster of four baculoviruses that are infective for different Agrotis species. Belonging further to different baculovirus genera, namely Alphabaculovirus and Betabaculovirus, respectively, AgseNPV-B and AgseGV are candidates to investigate virus interactions in co-infections. However, for the investigation of virus interactions on a cellular level, permissive insect cell-lines are needed. The cell line AiE1611T deriving from Agrotisipsilon eggs has been shown to be permissive for several Alphabaculovirus isolates. In this study, virus replication was followed based on microscopic analysis of infected and transfected cells, as well as on a molecular level by PCR of DNA and cDNA of selected baculovirus transcripts. While the permissivity was not verified for AgseGV, AgseNPV-B produced occlusion bodies in both infection with hemolymph of infected larvae and Lipofectamin transfection with AgseNPV-B genomic DNA. In addition to the possibility to investigate virus interaction of AgseNPV-B with other alphabaculoviruses, the permissivity of AiE1611T for AgseNPV-B further offers the possibility a biological selection to separate AgseNPV-B from AgseGV.


Assuntos
Granulovirus/fisiologia , Mariposas/virologia , Nucleopoliedrovírus/fisiologia , Replicação Viral , Animais
16.
Int J Mol Sci ; 18(11)2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29099796

RESUMO

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 Cryptophlebialeucotreta 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.


Assuntos
Genoma Viral , Granulovirus/genética , Lepidópteros/fisiologia , Lepidópteros/virologia , Controle Biológico de Vetores/métodos , Animais , Sequência de Bases , Agentes de Controle Biológico/metabolismo , DNA Viral/genética , Granulovirus/fisiologia , Larva/fisiologia , Larva/virologia , Fases de Leitura Aberta , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , África do Sul
17.
Viruses ; 9(9)2017 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-28869567

RESUMO

The use of Cydia pomonella granulovirus (CpGV) isolates as biological control agents of codling moth (CM) larvae is important in organic and integrated pome fruit production worldwide. The commercially available isolates CpGV-0006, CpGV-R5, and CpGV-V15 have been selected for the control of CpGV resistant CM populations in Europe. In infection experiments, CpGV-0006 and CpGV-R5 were able to break type I resistance and to a lower extent also type III resistance, whereas CpGV-V15 overcame type I and the rarely occurring type II and type III resistance. The genetic background of the three isolates was investigated with next generation sequencing (NGS) tools by comparing their nucleotide compositions to whole genome alignments of five CpGV isolates representing the known genetic diversity of the CpGV genome groups A to E. Based on the distribution of single nucleotide polymorphisms (SNPs) in Illumina sequencing reads, we found that the two isolates CpGV-0006 and CpGV-R5 have highly similar genome group compositions, consisting of about two thirds of the CpGV genome group E and one third of genome group A. In contrast, CpGV-V15 is composed of equal parts of CpGV genome group B and E. According to the identified genetic composition of these isolates, their efficacy towards different resistance types can be explained and predictions on the success of resistance management strategies in resistant CM populations can be made.


Assuntos
Genoma Viral , Granulovirus/genética , Granulovirus/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mariposas/virologia , Animais , Europa (Continente) , Variação Genética , Granulovirus/isolamento & purificação , Granulovirus/patogenicidade , Larva/virologia , Controle Biológico de Vetores , Polimorfismo de Nucleotídeo Único
18.
Viruses ; 9(8)2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28820456

RESUMO

Six complete genome sequences of Cydia pomonella granulovirus (CpGV) isolates from Mexico (CpGV-M and CpGV-M1), England (CpGV-E2), Iran (CpGV-I07 and CpGV-I12), and Canada (CpGV-S) were aligned and analyzed for genetic diversity and evolutionary processes. The selected CpGV isolates represented recently identified phylogenetic lineages of CpGV, namely, the genome groups A to E. The genomes ranged from 120,816 bp to 124,269 bp. Several common differences between CpGV-M, -E2, -I07, -I12 and -S to CpGV-M1, the first sequenced and published CpGV isolate, were highlighted. Phylogenetic analysis based on the aligned genome sequences grouped CpGV-M and CpGV-I12 as the most derived lineages, followed by CpGV-E2, CpGV-S and CpGV-I07, which represent the most basal lineages. All of the genomes shared a high degree of co-linearity, with a common setup of 137 (CpGV-I07) to 142 (CpGV-M and -I12) open reading frames with no translocations. An overall trend of increasing genome size and a decrease in GC content was observed, from the most basal lineage (CpGV-I07) to the most derived (CpGV-I12). A total number of 788 positions of single nucleotide polymorphisms (SNPs) were determined and used to create a genome-wide SNP map of CpGV. Of the total amount of SNPs, 534 positions were specific for exactly one of either isolate CpGV-M, -E2, -I07, -I12 or -S, which allowed the SNP-based detection and identification of all known CpGV isolates.


Assuntos
Evolução Molecular , Granulovirus/genética , Mariposas/virologia , Polimorfismo de Nucleotídeo Único , Animais , Sequência de Bases , Canadá , Genoma Viral , Granulovirus/classificação , Granulovirus/isolamento & purificação , Irã (Geográfico) , México , Filogenia , Proteínas Virais/química , Proteínas Virais/genética
19.
Appl Environ Microbiol ; 83(17)2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28667116

RESUMO

Different isolates of Cydia pomonella granulovirus (CpGV) are used worldwide to control codling moth larvae (Cydia pomonella) in pome fruit production. Two types of dominantly inherited field resistance of C. pomonella to CpGV have been recently identified: Z-chromosomal type I resistance and autosomal type II resistance. In the present study, a CpGV-resistant C. pomonella field population (termed SA-GO) from northeastern Germany was investigated. SA-GO individuals showed cross-resistance to CpGV isolates of genome group A (CpGV-M) and genome group E (CpGV-S), whereas genome group B (CpGV-E2) was still infective. Crossing experiments between individuals of SA-GO and the susceptible C. pomonella strain CpS indicated the presence of a dominant autosomal inheritance factor. By single-pair inbreeding of SA-GO individuals for two generations, the genetically more homogenous strain CpRGO was generated. Resistance testing of CpRGO neonates with different CpGV isolates revealed that isolate CpGV-E2 and isolates CpGV-I07 and -I12 were resistance breaking. When progeny of hybrid crosses and backcrosses between individuals of resistant strain CpRGO and susceptible strain CpS were infected with CpGV-M and CpGV-S, resistance to CpGV-S appeared to be autosomal and dominant for larval survivorship but recessive when success of pupation of the hybrids was considered. Inheritance of resistance to CpGV-M, however, is proposed to be both autosomal and Z linked, since Z linkage of resistance was needed for pupation. Hence, we propose a further type III resistance to CpGV in C. pomonella, which differs from type I and type II resistance in its mode of inheritance and response to CpGV isolates from different genome groups.IMPORTANCE The baculovirus Cydia pomonella granulovirus (CpGV) is registered and applied as a biocontrol agent in nearly all pome fruit-growing countries worldwide to control codling moth caterpillars in an environmentally friendly manner. It is therefore the most widely used commercial baculovirus biocontrol agent. Since 2005, field resistance of codling moth to CpGV products has been observed in more than 40 field plantations in Europe, threatening organic and integrated apple production. Knowledge of the inheritance and mechanism(s) of resistance is indispensable for the understanding of host response to baculovirus infection on the population level and the coevolutionary arms race between virus and host, as well as for the development of appropriate resistance management strategies. Here, we report a codling moth field population with a new type of resistance, which appears to follow a highly complex inheritance in regard to different CpGV isolates.


Assuntos
Granulovirus/genética , Granulovirus/isolamento & purificação , Mariposas/virologia , Animais , Europa (Continente) , Ligação Genética , Granulovirus/classificação , Granulovirus/fisiologia , Padrões de Herança , Larva/imunologia , Larva/virologia , Malus/parasitologia , Mariposas/crescimento & desenvolvimento , Mariposas/imunologia , Doenças das Plantas/parasitologia
20.
PLoS One ; 12(6): e0179157, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28640892

RESUMO

Commercial Cydia pomonella granulovirus (CpGV) products have been successfully applied to control codling moth (CM) in organic and integrated fruit production for more than 30 years. Since 2005, resistance against the widely used isolate CpGV-M has been reported from different countries in Europe. The inheritance of this so-called type I resistance is dominant and linked to the Z chromosome. Recently, a second form (type II) of CpGV resistance in CM was reported from a field population (NRW-WE) in Germany. Type II resistance confers reduced susceptibility not only to CpGV-M but to most known CpGV isolates and it does not follow the previously described Z-linked inheritance of type I resistance. To further analyze type II resistance, two CM strains, termed CpR5M and CpR5S, were generated from parental NRW-WE by repeated mass crosses and selection using the two isolates CpGV-M and CpGV-S, respectively. Both CpR5M and CpR5S were considered to be genetically homogeneous for the presence of the resistance allele(s). By crossing and backcrossing experiments with a susceptible CM strain, followed by resistance testing of the offspring, an autosomal dominant inheritance of resistance was elucidated. In addition, cross-resistance to CpGV-M and CpGV-S was detected in both strains, CpR5M and CpR5S. To test the hypothesis that the autosomal inheritance of type II resistance was caused by a large interchromosomal rearrangement involving the Z chromosome, making type I resistance appear to be autosomal in these strains; fluorescence in situ hybridization with bacterial artificial chromosome probes (BAC-FISH) was used to physically map the Z chromosomes of different CM strains. Conserved synteny of the Z-linked genes in CpR5M and other CM strains rejects this hypothesis and argues for a novel genetic and functional mode of resistance in CM populations with type II resistance.


Assuntos
Genoma Viral/genética , Granulovirus/genética , Granulovirus/fisiologia , Padrões de Herança , Mariposas/genética , Mariposas/virologia , Animais , Cromossomos de Insetos/genética , Hibridização Genética , Mariposas/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA