Relating Mobility of dsRNA in Nanoporous Silica Particles to Loading and Release Behavior.

Nanoparticle delivery of polynucleic acids traditionally relies on the modulation of surface interactions to achieve loading and release. This work investigates the additional role of confinement in mobility of dsRNA (84 and 282 base pair (bp) sequences of ) as a function of silica nanopore size (nonporous, 3.9, 8.

Effect of Confinement in Nanopores on RNA Interactions with Functionalized Mesoporous Silica Nanoparticles.

Amine-functionalized mesoporous silica nanoparticles (MSNPAs) are ideal carriers for oligonucleotides for gene delivery and RNA interference. This investigation examines the thermodynamic driving force of interactions of double-stranded (ds) RNA with MSNPAs as a function of RNA length (84 and 282 base pair) and particle pore diameter (nonporous, 2.7, 4.

Improving the baculovirus expression vector system with vankyrin-enhanced technology.

The baculovirus expression vector system (BEVS) is a widely used platform for the production of recombinant eukaryotic proteins. However, the BEVS has limitations in comparison to other higher eukaryotic expression systems. First, the insect cell lines used in the BEVS cannot produce glycoproteins with complex-type N-glycosylation patterns.

De novo sequencing and transcriptome analysis of female venom glands of ectoparasitoid Bracon hebetor (Say.) (Hymenoptera: Braconidae).

Venom is a key-factor in the regulation of host physiology by parasitic Hymenoptera and a potentially rich source of novel bioactive substances for biotechnological applications. The limited study of venom from the ectoparasitoid Bracon hebetor, a tiny wasp that attacks larval pest insects of field and stored products and is thus a potential insect control agent, has not described the full complement and composition of these biomolecules. To have a comprehensive picture of genes expressed in the venom glands of B.

De novo sequencing and transcriptome analysis of venom glands of endoparasitoid Aenasius arizonensis (Girault) (=Aenasius bambawalei Hayat) (Hymenoptera, Encyrtidae).

Aenasius bambawalei Hayat (Encyrtidae: Hymenoptera) has been synonymized with Aenasius arizonensis (Girault) is a small, newly discovered endoparasitoid of the cotton mealybug Phenacoccuss solenopsis Tinsley (Pseudococcidae: Hemiptera), which completes its life cycle inside the body of its host and it is a potential insect control tool. Despite the acquired knowledge regarding host-parasitoid interaction, little information is available on the factors of parasitoid origin able to modulate mealybug physiology. The components of A.

Specificities of ichnoviruses associated with campoplegine wasps: genome, genes and role in host-parasitoid interaction.

Ichnoviruses (IVs), unique symbiotic viruses carried by ichneumonid campoplegine wasps, derive from integration of a paleo-ichnovirus into an ancestral wasp genome. The modern 'genome' is composed of both regions that are amplified, circularized and encapsidated into viral particles and non-encapsidated viral genomic regions involved in particle morphogenesis. Packaged genomes include multiple circular dsDNAs encoding many genes mostly organized in gene families.

Nancy E. Beckage (1950-2012): pioneer in insect host-parasite interactions.

Nancy E. Beckage is widely recognized for her pioneering work in the field of insect host-parasitoid interactions beginning with endocrine influences of the tobacco hornworm, Manduca sexta, host and its parasitoid wasp Apanteles congregatus (now Cotesia congregata) on each other's development. Moreover, her studies show that the polydnavirus carried by the parasitoid wasp not only protects the parasitoid from the host's immune defenses, but also is responsible for some of the developmental effects of parasitism.

A supracellular system of actin-lined canals controls biogenesis and release of virulence factors in parasitoid venom glands.

Parasitoid wasps produce virulence factors that bear significant resemblance to viruses and have the ability to block host defense responses. The function of these virulence factors, produced predominantly in wasp venom glands, and the ways in which they interfere with host development and physiology remain mysterious. Here, we report the discovery of a specialized system of canals in venom glands of five parasitoid wasps that differ in their infection strategies.

Shared and species-specific features among ichnovirus genomes.

During egg-laying, some endoparasitic wasps transmit a polydnavirus to their caterpillar host, causing physiological disturbances that benefit the wasp larva. Members of the two recognized polydnavirus taxa, ichnovirus (IV) and bracovirus (BV), have large, segmented, dsDNA genomes containing virulence genes expanded into families. A recent comparison of IV and BV genomes revealed taxon-specific features, but the IV database consisted primarily of the genome sequence of a single species, the Campoletis sonorensis IV (CsIV).

Antibiosis-type insect resistance in transgenic plants expressing a teratocyte secretory protein (TSP14) gene from a hymenopteran endoparasite (Microplitis croceipes).

We have isolated a teratocyte secretory protein (TSP14) gene product from a hymenopteran endoparasite that disrupts the growth of lepidopteran insect larvae. To evaluate the insecticidal activity of TSP14 for the protection of crops from insect damage, chimeric gene constructs of TSP14 were expressed in transgenic plants. The coding sequence of the TSP14 gene, with and without its native signal peptide, was placed between the modified peanut chlorotic streak virus (PClSV) full-length transcript (FLt) promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene.

Divergences in protein activity and cellular localization within the Campoletis sonorensis Ichnovirus Vankyrin family.

Ichnoviruses (IVs) occur in obligate symbiotic associations with endoparasitic ichneumonid wasps. IVs are injected with eggs during parasitization, where viral infection and gene expression alter host physiology to ensure endoparasitoid survival. The seven Campoletis sonorensis IV (CsIV) vankyrin genes encode proteins that possess ankyrin repeat domains resembling the inhibitory domains of NF-kappaB transcription factor inhibitors (IkappaBs).

Potential uses of Cys-motif and other polydnavirus genes in biotechnology.

Exploiting the ability of insect pathogens, parasites, and predators to control natural and damaging insect populations is a cornerstone of biological control. Here we focus on an unusual group of viruses, the polydnaviruses (PDV), which are obligate symbionts of some hymenopteran insect parasitoids. PDVs have a variety of important pathogenic effects on their parasitized hosts.

Polydnavirus genes that enhance the baculovirus expression vector system.

The baculovirus expression vector system (BEVS) is a powerful and versatile system for protein expression, which has many advantages. However, a limitation of any lytic viral expression system, including BEVS, is that death and lysis of infected insect cells terminates protein production. This results in interruption of protein production and higher production costs due to the need to set up new infections, maintain uninfected cells, and produce pure viral stocks.

Response of immunocompetent and immunosuppressed Spodoptera littoralis larvae to baculovirus infection.

The Mediterranean lepidopteran pest Spodoptera littoralis is highly resistant to infection with the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) via the oral route, but highly sensitive to infection with budded virus (BV) via the intrahaemocoelic route. To study the fate of AcMNPV infection in S. littoralis, vHSGFP, an AcMNPV recombinant that expresses the reporter green fluorescent protein gene under the control of the Drosophila heat-shock promoter, and high-resolution fluorescence microscopy were utilized.

Effect of Campoletis sonorensis ichnovirus cys-motif proteins on Heliothis virescens larval development.

Polydnaviruses are obligate symbionts of some parasitic hymenopteran wasps responsible for modifying the physiology of their host lepidopteran larvae to benefit the endoparasite. Injection of Campoletis sonorensis ichnovirus (CsIV) into Heliothis virescens larvae alters larval growth, development and immunity but genes responsible for alterations of host physiology are not well described. Recent studies of polydnavirus genomes establish that these genomes encode families of related genes expressed in parasitized larvae.

Polydnavirus genomes reflect their dual roles as mutualists and pathogens.

Symbionts often exhibit significant reductions in genome complexity while pathogens often exhibit increased complexity through acquisition and diversification of virulence determinants. A few organisms have evolved complex life cycles in which they interact as symbionts with one host and pathogens with another. How the predicted and opposing influences of symbiosis and pathogenesis affect genome evolution in such instances, however, is unclear.

Ikappabeta-related vankyrin genes in the Campoletis sonorensis ichnovirus: temporal and tissue-specific patterns of expression in parasitized Heliothis virescens lepidopteran hosts.

Polydnaviruses (PDVs) are unusual insect viruses that occur in obligate symbiotic associations with parasitic ichneumonid (ichnoviruses, or IVs) and braconid (bracoviruses, or BVs) wasps. PDVs are injected with eggs, ovarian proteins, and venom during parasitization. Following infection of cells in host tissues, viral genes are expressed and their products function to alter lepidopteran host physiology, enabling endoparasitoid development.

Quantitative analysis of hemocyte morphological abnormalities associated with Campoletis sonorensis parasitization.

Endoparasitoids of arthropods evoke host cellular immune responses that result in hemocytic encapsulation of the endoparasitoid, unless these responses are disrupted by the parasite. Our interest has focused on mutualistic viruses found in some hymenopteran endoparasitoids that disrupt hemocyte function and prevent encapsulation. Specifically, the Campoletis sonorensis polydnavirus interacts with wasp factors to suppress immunity via expression of intracellular and secreted viral proteins.

Evaluation of early fetal loss induced by gavage with eastern tent caterpillars in pregnant mares.

Objective: To determine whether gavage of pregnant mares (housed without access to pasture) with starved eastern tent caterpillars (ETCs) or their excreta is associated with early fetal loss (EFL), panophthalmitis, or pericarditis.

Design: Randomized clinical trial.

Animals: 15 mares.

Eastern tent caterpillars (Malacosoma americanum) cause mare reproductive loss syndrome.

A new equine abortigenic disease, mare reproductive loss syndrome (MRLS), was recognized and significantly impacted the Ohio Valley in the springs of 2001 and 2002. MRLS caused approximately 330 million US dollars in losses in 2001. An epidemiological investigation of MRLS associated occurrence of the disease with exposure to eastern tent caterpillars (M.

Polydnavirus genes and genomes: emerging gene families and new insights into polydnavirus replication.

Polydnavirus genome sequencing is providing new insights into viral genome organization and viral gene function. Sequence analyses demonstrate that the genomes of these viral mutualists are largely noncoding but maintain genes and gene families that are unrelated to other viral genes. Interestingly, these organizational patterns in polydnavirus genomes are evident in both the bracovirus and ichnovirus genera, even though these two genera are evolutionarily unrelated.

Diversifying selection in a parasitoid's symbiotic virus among genes involved in inhibiting host immunity.

During parasitization of their hosts some insect parasitoids deliver resident viruses which encode genes that must be expressed in the host for successful parasitization. Among these viruses the Campoletis sonorensis Ichnovirus has been well studied and encodes a cys-motif gene family implicated in disruption of host immunity and other physiological systems. Members of this gene family encode one or more intercystine-knot structural motifs in which the non-cysteine residues of the motif are variable.