Granulovirus
Baculoviridae
Nucleopolyhedrovirus
Open Reading Frames
Larva
Molecular Sequence Data
Homologous recombination between the inverted terminal repeats of defective transposon TCp3.2 causes an inversion in the genome of Cydia pomonella granulovirus. (1/31)
In this study, a new mutant of the Cydia pomonella granulovirus (CpGV), which shows spontaneous inversion of a transposable element during in vivo replication, is described. CpGV-MCp4 is a natural mutant of CpGV-M, containing the transposable element TCp3.2, which originated from the genome of the host C. pomonella. During in vivo cloning studies of CpGV-MCp4, a mutant called CpGV-MCp4inv was isolated. CpGV-MCp4inv shows heterogeneity in the genome area of transposon insertion. Restriction mapping, PCR analysis and subsequent sequence analysis gave strong evidence that an inversion of TCp3.2 is caused by homologous recombination between the long inverted terminal repeats (ITRs) of the transposon. This finding demonstrated that extensive homologous repeat regions such as the ITRs of transposons cause inversions by homologous recombination during in vivo replication. The observed in vivo inversion between the ITRs can be considered as a model for the contribution of repeated sequences in the genome rearrangement of baculoviruses and a source for genetic heterogeneity among different baculoviruses and baculovirus genotypes. (+info)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. (2/31)
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. (+info)Characterization of Spodoptera exigua multicapsid nucleopolyhedrovirus ORF17/18, a homologue of Xestia c-nigrum granulovirus ORF129. (3/31)
Spodoptera exigua multicapsid nucleopolyhedrovirus (SeMNPV) contains a number of genes with a homologue found so far only in a distantly related baculovirus. One of these, SeMNPV ORF17/18 (Se17/18) shares 55% amino acid similarity to ORF129 of Xestia c-nigrum granulovirus (XcGV). Se17/18 was transcribed in cultured S. exigua 301 cells, as a polyadenylated transcript of 1.1 kb. 5'-RACE analysis demonstrated that Se17/18 transcripts started at 134, 131 and 126 nt upstream of the putative translational start codon. These sites overlap with a baculovirus consensus early promoter motif. Se17/18 transcripts were detected by Northern blot analysis and RT-PCR with increasing abundance from 8 h to 24 h post infection (p.i.) and still present until 72 h p.i. A C-terminal GFP-fusion protein of Se17/18 was primarily localized in the cytoplasm of Se301 and Sf21 cells. A chicken polyclonal antiserum was raised that reacted specifically to Se17/18 protein produced in E. coli. However, no immunoreactive protein was detected in SeMNPV-infected Se301 cells and S. exigua larvae, neither in concentrated BV and ODV preparations. These observations and the inability to detect a C-terminal GFP-fusion protein of Se17/18 in Se301 cells using a GFP antibody suggest that Se17/18 protein is present, if at all, in spurious amounts. Based on the low homology of the Se17/18 protein to (methyl) transferases its possible involvement in transcription regulation is discussed. (+info)Identification and characterization of a putative baculoviral transcriptional factor IE-1 from Choristoneura fumiferana granulovirus. (4/31)
A gene that encodes a protein homologue to baculoviral IE-1 was identified and sequenced in the genome of the Choristoneura fumiferana granulovirus (ChfuGV). The gene has an 1278 nucleotide (nt) open-reading frame (ORF) that encodes 426 amino acids with an estimated molecular weight of 50.33 kDa. At the nucleotide level, several cis-acting regulatory elements were detected within the promoter region of the ie-1 gene of ChfuGV along with other studied granuloviruses (GVs). Two putative CCAAT elements were detected within the noncoding leader region of this gene; one was located on the opposite strand at -92 and the other at -420 nt from the putative start triplet. Two baculoviral late promoter motifs (TAAG) were also detected within the promoter region of the ie-1 gene of ChfuGV. A single polyadenylation signal, AATAAA, was located 18nt downstream of the putative translational stop codon of ie-1 from ChfuGV. At the protein level, the amino acid sequence data that was derived from the nucleotide sequence in ChfuGV IE-1 was compared to those of the Cydia pomonella granulovirus (CpGV), Xestia c-nigrum granulovirus (XcGV) and Plutella xylostella granulovirus (PxGV). The C-terminal regions of the granuloviral IE-1 sequences appeared to be more conserved when compared to the N-terminal regions. A domain, similar to the basic helix-loop-helix like (bHLH-like) domain in NPVs, was detected at the C-terminal region of IE-1 from ChfuGV (residues 387 to 414). A phylogenetic tree for baculoviral IE-1 was constructed using a maximum parsimony analysis. A phylogenetic estimation demonstrates that ChfuGV IE-1 is most closely related to that of CpGV. (+info)Identification and characterization of a conserved baculoviral structural protein ODVP-6E/ODV-E56 from Choristoneura fumiferana granulovirus. (5/31)
A gene that encodes a homologue to baculoviral ODVP-6E/ODV-E56, a baculoviral envelope-associated viral structural protein, has been identified and sequenced on the genome of Choristoneura fumiferana granulovirus (ChfuGV). The ChfuGV odvp-6e/odv-e56 gene was located on an 11-kb BamHI subgenomic fragment using different sets of degenerated primers, which were designed using the results of the protein sequencing of a major 39 kDa structural protein that is associated with the occlusion-derived virus (ODV). The gene has a 1062 nucleotide (nt) open-reading frame (ORF) that encodes a protein with 353 amino acids with a predicted molecular mass of 38.5 kDa. The amino acid sequence data that was derived from the nucleotide sequence in ChfuGV was compared to those of other baculoviruses. ChfuGV ODVP-6E/ODV-E56, along with other baculoviral ODVP-6E/ODV-E56 proteins, all contained two putative transmembrane domains at their C-terminus. Several putative N- and O-glycosylation, N-myristoylation, and phosphorylation sites were detected in the ChfuGV ODVP-6E/ODV-E56 protein. A similar pattern was detected when a hydrophobicity-plots comparison was performed on ChfuGV ODVP-6E/ODV-E56 with other baculoviral homologue proteins. At the nucleotide level, a late promoter motif (GTAAG) was located at -14 nt upstream to the start codon of the ChfuGV odvp-6e/odv-e56 gene. A slight variant of the polyadenylation signal, AATAAT, was detected at the position +10 nt that is downstream from the termination signal. A phylogenetic tree for baculoviral ODVP-6E/ODV-E56 was constructed using a maximum parsimony analysis. The phylogenetic estimation demonstrated that ChfuGV ODVP-6E/ODV-E56 is most closely related to those of Cydia pomonella granulovirus (CpGV) and Plutella xylostella granulovirus (PxGV). (+info)The complete sequence of the Adoxophyes orana granulovirus genome. (6/31)
The nucleotide sequence of the Adoxophyes orana granulovirus (AdorGV) DNA genome was determined and analysed. The genome contains 99,657 bp and has an A + T content of 65.5%. The analysis predicted 119 ORFs of 150 nucleotides or larger that showed minimal overlap. Of these putative genes, 104 (87%) were homologous to genes identified previously in other baculoviruses. The mean overall amino acid identity of AdorGV ORFs was highest with CpGV ORFs at 48%. Sixty-three ORFs were conserved among all lepidopteran baculoviruses and are considered to be common baculoviral genes. Several genes reported to have major roles in baculovirus biology were not found in the AdorGV genome. These included chitinase and cathepsin, which are involved in the liquefaction of the host, which explains why AdorGV-infected insects do not degrade in a typical manner. The AdorGV genome encoded two inhibitor of apoptosis (iap) genes iap-3 and iap-5. Among all of the granuloviruses genomes there was a very high level of gene collinearity. The genes shared by AdorGV and CpGV had exactly the same order along the genome with the exception of one gene, iap-3. The AdorGV genome did not contain typical homologous region (hr) sequences. However, it contained nine repetitive regions in the genome. (+info)Choristoneura fumiferana Granulovirus p74 protein, a highly conserved baculoviral envelope protein. (7/31)
A gene that encodes a homologue to baculoviral p74, an envelope-associated viral structural protein, has been identified and sequenced on the genome of Choristoneura fumiferana granulovirus (ChfuGV). A part of the ChfuGV p74 gene was located on an 8.9 kb BamHI subgenomic fragment using different sets of degenerated primers. These were designed using the results of the protein sequencing of a major 74 kDa structural protein that is associated with the occlusion-derived virus (ODV). The gene has a 1992 nucleotide (nt) open-reading frame (ORF) that encodes a protein with 663 amino acids with a predicted molecular mass of 74,812 Da. Comparative studies revealed the presence of two major conserved regions in the ChfuGV p74 protein. This study also shows that all of the p74 proteins contain two putative transmembrane domains at their C-terminal segments. At the nucleotide sequence level, two late promoter motifs (TAAG and GTAAG) were located upstream of the first ATG of the p74 gene. The gene contained a canonical poly(A) signal, AATAAA, at its 3 non-translated region. A phylogenetic tree for baculoviral p74 was constructed using a maximum parsimony analysis. The phylogenetic estimation demonstrated that ChfuGV p74 is related the closest to those of Cydia pomonella granulovirus (CpGV) and Phthorimaea operculella granulovirus (PhopGV). (+info)The genome of the Cryptophlebia leucotreta granulovirus. (8/31)
The genome of the Cryptophlebia leucotreta granulovirus (CrleGV) was sequenced and analyzed. The double-stranded circular genome contains 110907 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. (+info)I'm sorry for any confusion, but "Granulovirus" is not a widely recognized medical or scientific term with a specific definition in the context of human health. The term "granulovirus" is used in the field of virology to refer to a type of virus that is characterized by the production of granular-shaped virions (infectious particles) during its replication cycle. This term is most commonly associated with certain types of baculoviruses, which are viruses that infect insects.
If you have any questions related to human health or a specific medical concern, I would be happy to try and help clarify those for you!
I believe there may be some confusion in your question. "Moths" are not a medical term, but rather they are a group of insects closely related to butterflies. They belong to the order Lepidoptera and are characterized by their scales covering their wings and body. If you have any questions about moths or if you meant to ask something else, please let me know!
Baculoviridae is a family of large, double-stranded DNA viruses that infect arthropods, particularly insects. The virions (virus particles) are enclosed in a rod-shaped or occlusion body called a polyhedron, which provides protection and stability in the environment. Baculoviruses have a wide host range within the order Lepidoptera (moths and butterflies), Hymenoptera (sawflies, bees, wasps, and ants), and Diptera (flies). They are important pathogens in agriculture and forestry, causing significant damage to insect pests.
The Baculoviridae family is divided into four genera: Alphabaculovirus, Betabaculovirus, Gammabaculovirus, and Deltabaculovirus. The two most well-studied and economically important genera are Alphabaculovirus (nuclear polyhedrosis viruses or NPVs) and Betabaculovirus (granulosis viruses or GVs).
Baculoviruses have a biphasic replication cycle, consisting of a budded phase and an occluded phase. During the budded phase, the virus infects host cells and produces enveloped virions that can spread to other cells within the insect. In the occluded phase, large numbers of non-enveloped virions are produced and encapsidated in a protein matrix called a polyhedron. These polyhedra accumulate in the infected insect's tissues, providing protection from environmental degradation and facilitating transmission to new hosts through oral ingestion or other means.
Baculoviruses have been extensively studied as models for understanding viral replication, gene expression, and host-pathogen interactions. They also have potential applications in biotechnology and pest control, including the production of recombinant proteins, gene therapy vectors, and environmentally friendly insecticides.
I'm sorry for any confusion, but "Lepidoptera" is not a medical term. It is a taxonomic order that includes moths and butterflies, which are insects known for their distinctive wing scales. This term is used in the field of biology, not medicine.
A viral genome is the genetic material (DNA or RNA) that is present in a virus. It contains all the genetic information that a virus needs to replicate itself and infect its host. The size and complexity of viral genomes can vary greatly, ranging from a few thousand bases to hundreds of thousands of bases. Some viruses have linear genomes, while others have circular genomes. The genome of a virus also contains the information necessary for the virus to hijack the host cell's machinery and use it to produce new copies of the virus. Understanding the genetic makeup of viruses is important for developing vaccines and antiviral treatments.
A nucleopolyhedrovirus (NPV) is a type of large, complex DNA virus that infects insects, particularly members of the order Lepidoptera (moths and butterflies). NPVs are characterized by their ability to produce multiple virions within a single polyhedral occlusion body, which provides protection for the virions in the environment and facilitates their transmission between hosts.
NPVs replicate in the nucleus of infected cells, where they induce the production of large quantities of viral proteins that ultimately lead to the lysis of the host cell. The virions are then released and can infect other cells or be transmitted to other insects. NPVs are important pathogens of many agricultural pests, and some species have been developed as biological control agents for use in integrated pest management programs.
An open reading frame (ORF) is a continuous stretch of DNA or RNA sequence that has the potential to be translated into a protein. It begins with a start codon (usually "ATG" in DNA, which corresponds to "AUG" in RNA) and ends with a stop codon ("TAA", "TAG", or "TGA" in DNA; "UAA", "UAG", or "UGA" in RNA). The sequence between these two points is called a coding sequence (CDS), which, when transcribed into mRNA and translated into amino acids, forms a polypeptide chain.
In eukaryotic cells, ORFs can be located in either protein-coding genes or non-coding regions of the genome. In prokaryotic cells, multiple ORFs may be present on a single strand of DNA, often organized into operons that are transcribed together as a single mRNA molecule.
It's important to note that not all ORFs necessarily represent functional proteins; some may be pseudogenes or result from errors in genome annotation. Therefore, additional experimental evidence is typically required to confirm the expression and functionality of a given ORF.
A larva is a distinct stage in the life cycle of various insects, mites, and other arthropods during which they undergo significant metamorphosis before becoming adults. In a medical context, larvae are known for their role in certain parasitic infections. Specifically, some helminth (parasitic worm) species use larval forms to infect human hosts. These invasions may lead to conditions such as cutaneous larva migrans, visceral larva migrans, or gnathostomiasis, depending on the specific parasite involved and the location of the infection within the body.
The larval stage is characterized by its markedly different morphology and behavior compared to the adult form. Larvae often have a distinct appearance, featuring unsegmented bodies, simple sense organs, and undeveloped digestive systems. They are typically adapted for a specific mode of life, such as free-living or parasitic existence, and rely on external sources of nutrition for their development.
In the context of helminth infections, larvae may be transmitted to humans through various routes, including ingestion of contaminated food or water, direct skin contact with infective stages, or transmission via an intermediate host (such as a vector). Once inside the human body, these parasitic larvae can cause tissue damage and provoke immune responses, leading to the clinical manifestations of disease.
It is essential to distinguish between the medical definition of 'larva' and its broader usage in biology and zoology. In those fields, 'larva' refers to any juvenile form that undergoes metamorphosis before reaching adulthood, regardless of whether it is parasitic or not.
Gene order, in the context of genetics and genomics, refers to the specific sequence or arrangement of genes along a chromosome. The order of genes on a chromosome is not random, but rather, it is highly conserved across species and is often used as a tool for studying evolutionary relationships between organisms.
The study of gene order has also provided valuable insights into genome organization, function, and regulation. For example, the clustering of genes that are involved in specific pathways or functions can provide information about how those pathways or functions have evolved over time. Similarly, the spatial arrangement of genes relative to each other can influence their expression levels and patterns, which can have important consequences for phenotypic traits.
Overall, gene order is an important aspect of genome biology that continues to be a focus of research in fields such as genomics, genetics, evolutionary biology, and bioinformatics.
Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.
Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.