Publications by authors named "Rasgon J"

Flaviviruses pose a major public health concern across the globe. Among them, Zika virus (ZIKV) is an emerging and reemerging arthropod-borne flavivirus that has become a major international public health problem following multiple large outbreaks over the past two decades. The majority of infections caused by ZIKV exhibit mild symptoms.

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Japanese encephalitis virus (JEV) NS2B-NS3 is a protein complex composed of NS3 proteases and an NS2B co-factor. The N-terminal protease domain (180 residues) of NS3 (NS3(pro)) interacts directly with a central 40-amino acid hydrophilic domain of NS2B (NS2B(H)) to form an active serine protease. In this study, the recombinant NS2B(H)-NS3(pro) proteases were prepared in and used to compare the enzymatic activity between genotype I (GI) and III (GIII) NS2B-NS3 proteases.

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Wolbachia pipientis (= Wolbachia) has promise as a tool to suppress virus transmission by Aedes aegypti mosquitoes. However, Wolbachia can have variable effects on mosquito-borne viruses. This variation remains poorly characterized, yet the multimodal effects of Wolbachia on diverse pathogens could have important implications for public health.

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Female mosquitoes are reproductively obligate bloodfeeders which feed on vertebrate blood to obtain nutrients required for egg production (driving transmission of vector-borne pathogens in the process), and which rely on plant sugars for their non-reproductive energy requirements. Male mosquitoes, on the other hand, are thought to rely exclusively on plant sugars for their energetic needs; indeed, this dichotomy is one of the central tenets of medical entomology. Here, we show that male and mosquitoes will readily take blood from a membrane feeder when reared under dehydration conditions with no toxic effects.

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Article Synopsis
  • West Nile virus (WNV) is the most common mosquito-related illness in the USA, and there are no vaccines or treatments for it right now.
  • A study looked at how an insect-specific virus called Eilat virus (EILV) affects WNV in both mosquito cells and real mosquitoes.
  • EILV was able to lower the levels of two different WNV strains in mosquito cells, but in mosquitoes, it helped one strain more than the other over time.
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Mushroom cultivation vastly improves the yield of mushrooms under optimized, controlled conditions, but may be susceptible to opportunistic colonization by pest species that can establish themselves, as well as the pathogens and pests they may transmit. Here, we describe our investigation into the bacterial communities of adult (Diptera: Sciaridae) and (Diptera: Phoridae) collected from button mushroom () production houses in Pennsylvania. We collected adult flies and sequenced the hypervariable v4 region of the bacterial 16S rRNA using the Illumina MiSeq.

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  • Mosquitoes in semi-arid regions adapt to drought by increasing their blood-feeding behavior, especially after prolonged dry periods.
  • Following a blood meal, these mosquitoes can survive for up to twenty days without water by refeeding, which helps them with hydration and nutrient needs without affecting egg production.
  • The changes in mosquito behavior during dry spells, like increased activity and sensitivity to CO2, are linked to higher survival rates and potentially greater transmission of diseases, such as arboviruses, during such dry conditions.
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  • The study focuses on improving gene editing techniques in a specific insect model that spreads Chagas disease, caused by parasites.
  • Researchers tested methods to deliver CRISPR-Cas9 gene editing tools to female insects' developing eggs and confirmed these methods led to successful changes in eye and cuticle color.
  • The findings pave the way for future gene editing in this insect species, potentially aiding the development of new strategies to control Chagas disease transmission.
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Multiple Wolbachia strains can block pathogen infection, replication and/or transmission in Aedes aegypti mosquitoes under both laboratory and field conditions. However, Wolbachia effects on pathogens can be highly variable across systems and the factors governing this variability are not well understood. It is increasingly clear that the mosquito host is not a passive player in which Wolbachia governs pathogen transmission phenotypes; rather, the genetics of the host can significantly modulate Wolbachia-mediated pathogen blocking.

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Background: Increasing global temperatures and unpredictable climatic extremes have contributed to the spread of vector-borne diseases. The mosquito Aedes aegypti is the main vector of multiple arboviruses that negatively impact human health, mostly in low socioeconomic areas of the world. Co-circulation and co-infection of these viruses in humans have been increasingly reported; however, how vectors contribute to this alarming trend remains unclear.

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  • Mosquito densoviruses (MDVs) are being researched for their potential as biocontrol agents and tools for manipulating mosquitoes in labs.
  • The study focused on identifying the nuclear localization signals (NLSs) and nuclear export signals (NESs) in MDV proteins, which are crucial for understanding how these viruses replicate and assemble in mosquito cells.
  • Findings from this analysis enhance our knowledge of MDV transport in the cell nucleus and provide a foundation for future applications in mosquito control and research.
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Japanese Encephalitis Virus (JEV) NS2B-NS3 is a protein complex composed of NS3 proteases and a NS2B cofactor. The N-terminal protease domain (180 residues) of NS3 (NS3(pro)) interacts directly with a central 40-amino acid hydrophilic domain of NS2B (NS2B(H)) to form an active serine protease. In this study, the recombinant NS2B(H)-NS3(pro) proteases were prepared in and used to compare the enzymatic activity between genotype I (GI) and III (GIII) NS2B-NS3 proteases.

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Relative humidity (RH) is an environmental variable that affects mosquito physiology and can impact pathogen transmission. Low RH can induce dehydration in mosquitoes, leading to alterations in physiological and behavioral responses such as blood-feeding and host-seeking behavior. We evaluated the effects of a temporal drop in RH (RH shock) on mortality and Mayaro virus vector competence in .

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Understanding the ecological and evolutionary processes that drive host-pathogen interactions is critical for combating epidemics and conserving species. The mite and deformed wing virus (DWV) are two synergistic threats to Western honeybee () populations across the globe. Distinct honeybee populations have been found to self-sustain despite infestations, including colonies within the Arnot Forest outside Ithaca, NY, USA.

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In the past 20 years, sequencing technologies have led to easy access to genomic data from nonmodel organisms in all biological realms. Insect genetic manipulation, however, continues to be a challenge due to various factors, including technical and cost-related issues. Traditional techniques such as microinjection of gene-editing vectors into early stage embryos have been used for arthropod transgenesis and the discovery of Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein (CRISPR-Cas) technologies allowed for targeted mutagenesis and the creation of knockouts or knock-ins in arthropods.

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Enhanced host immunity and competition for metabolic resources are two main competing hypotheses for the mechanism of -mediated pathogen inhibition in arthropods. Using an mosquito - somatic infection - O'nyong nyong virus (ONNV) model, we demonstrate that the mechanism underpinning -mediated virus inhibition is up-regulation of the Toll innate immune pathway. However, the viral inhibitory properties of were abolished by cholesterol supplementation.

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West Nile virus (WNV) is the leading cause of mosquito-borne illness in the United States. There are currently no human vaccines or therapies available for WNV, and vector control is the primary strategy used to control WNV transmission. The WNV vector is also a competent host for the insect-specific virus (ISV) Eilat virus (EILV).

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Increasing global temperatures and unpredictable climatic extremes have contributed to the spread of vector-borne diseases. The mosquito is the main vector of multiple arboviruses that negatively impact human health, mostly in low socioeconomic areas of the world. Co-circulation and co-infection of these viruses in humans have been increasingly reported; however, how vectors contribute to this alarming trend remains unclear.

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Eilat virus (EILV) is an insect-specific alphavirus that has the potential to be developed into a tool to combat mosquito-borne pathogens. However, its mosquito host range and transmission routes are not well understood. Here, we fill this gap by investigating EILV's host competence and tissue tropism in five mosquito species: Aedes aegypti, Culex tarsalis, Anopheles gambiae, Anopheles stephensi, and Anopheles albimanus.

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Autophagy is a critical modulator of pathogen invasion response in vertebrates and invertebrates. However, how it affects mosquito-borne viral pathogens that significantly burden public health remains underexplored. To address this gap, we use a genetic approach to activate macroautophagy/autophagy in the yellow fever mosquito (), infected with a recombinant Sindbis virus (SINV) expressing an autophagy activator.

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(=) has promise as a tool to suppress virus transmission by mosquitoes. However, can have variable effects on mosquito-borne viruses. This variation remains poorly characterized, yet the multimodal effects of on diverse pathogens could have important implications for public health.

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Ticks are important vectors of pathogenic viruses, bacteria, and protozoans to humans, wildlife, and domestic animals. Due to their life cycles, ticks face significant challenges related to water homeostasis. When blood-feeding, they must excrete water and ions, but when off-host (for stretches lasting several months), they must conserve water to avoid desiccation.

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Globalization and climate change have contributed to the simultaneous increase and spread of arboviral diseases. Cocirculation of several arboviruses in the same geographic region provides an impetus to study the impacts of multiple concurrent infections within an individual vector mosquito. Here, we describe coinfection and superinfection with the Mayaro virus (Togaviridae, ) and Zika virus (Flaviviridae, ) in vertebrate and mosquito cells, as well as Aedes aegypti adult mosquitoes, to understand the interaction dynamics of these pathogens and effects on viral infection, dissemination, and transmission.

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