Abstract Background To be transmitted by its mosquito vector, dengue virus (DENV) must infect midgut epithelial cells, replicate and disseminate into the hemocoel, finally salivary glands, which is essential for transmission. The extrinsic incubation period (EIP) very relevant epidemiologically time required from ingestion of until it can to next vertebrate host. EIP conditioned kinetics tropisms replication in vector. Here we document virogenesis DENV-2 newly-colonized Aedes aegypti...

A number of studies have shown that both innate and adaptive immune defense mechanisms greatly influence the course human dengue virus (DENV) infections, but little is known about response mosquito vector Aedes aegypti to arbovirus infection. We present evidence here a major component response, RNA interference (RNAi), an important modulator infections. The RNAi triggered by double-stranded (dsRNA), which occurs in cytoplasm as result positive-sense infection, leading production small...

Mosquitoes ( Aedes aegypti ) were genetically modified to exhibit impaired vector competence for dengue type 2 viruses (DENV-2). We exploited the natural antiviral RNA interference (RNAi) pathway in mosquito midgut by constructing an effector gene that expresses inverted-repeat (IR) derived from premembrane protein coding region of DENV-2 genome. The A. carboxypeptidase A promoter was used express IR epithelial cells after ingestion a bloodmeal. and inserted into genome white-eye Puerto Rico...

RNA interference (RNAi) is triggered in eukaryotic organisms by double-stranded (dsRNA), and it destroys any mRNA that has sequence identity with the dsRNA trigger. The RNAi pathway Anopheles gambiae can be silenced transfecting cells derived from exon of A. Argonaute2 ( AgAgo2 ) gene. We hypothesized may also act as an antagonist to alphavirus replication because viruses form during replication. Silencing expression would make mosquitoes more permissive virus infection. To determine whether...

ABSTRACT La Crosse virus (LACV) is a mosquito-transmitted member of the Bunyaviridae family that causes severe encephalitis in children. For LACV nonstructural protein NSs, previous overexpression studies with mammalian cells had suggested two different functions, namely induction apoptosis and inhibition RNA interference (RNAi). Here, we demonstrate mosquito persistently infected do not undergo mount specific RNAi response. Recombinant viruses either express (rLACV) or lack (rLACVdelNSs)...

Many viral pathogens cycle between humans and insects. These viruses must have evolved strategies for rapid adaptation to different host environments. However, the mechanistic basis process remains poorly understood. To study mosquito-human cycle, we examined changes in RNA structures of dengue virus genome during adaptation. Deep sequencing structure analysis, together with fitness evaluation, revealed a specialization elements 3'UTR. Adaptation mosquito or mammalian cells involved...

Aedes aegypti transmit pathogenic arboviruses while the mosquito itself tolerates infection. We examine a piRNA-based immunity that relies on acquisition of viral derived cDNA (vDNA) and how this pathway discriminates between self non-self. The piRNAs from these vDNAs are essential for virus control Piwi4 has central role in pathway. binds preferentially to virus-derived but not transposon-targeting piRNAs. Analysis episomal vDNA infected cells reveals molecules acquired through...

We describe the first comprehensive analysis of midgut metabolome Aedes aegypti, primary mosquito vector for arboviruses such as dengue, Zika, chikungunya and yellow fever viruses. Transmission these viruses depends on their ability to infect, replicate disseminate from several tissues in vector. The metabolic environments within play crucial roles processes. Since are enveloped, viral replication, assembly release occur cellular membranes primed through manipulation host metabolism....

The Flavivirus genus includes a large number of medically relevant pathogens that cycle between humans and arthropods. This host alternation imposes selective pressure on the viral population. Here, we found dengue virus, most important human pathogen transmitted by insects, evolved mechanism to differentially regulate production non-coding RNAs in mosquitos humans, with significant impact fitness each host. infections accumulate derived from 3'UTRs (known as sfRNAs), pathogenesis immune...

Double-stranded RNA (dsRNA) initiates cellular posttranscriptional responses that are collectively called silencing in a number of different organisms, including plants, nematodes, and fruit flies. In has been associated with protection from virus infection. this study, we demonstrate dsRNA-mediated interference also can act as viral defense mechanism mosquito cells. C6/36 (Aedes albopictus) cells were stably transformed plasmid designed to transcribe an inverted-repeat (irRNA) derived the...

Abstract Background The RNA interference (RNAi) pathway acts as an innate antiviral immune response in Aedes aegypti , modulating arbovirus infection of mosquitoes. Sindbis virus (SINV; family: Togaviridae genus: Alphavirus ) is that infects Ae. the laboratory. SINV strain TR339 encounters a midgut escape barrier (MEB) during . nature this not well understood. To investigate role central organ determining vector competence for arboviruses, we generated transgenic mosquitoes which RNAi was...

Controlled sex-, stage- and tissue-specific expression of antipathogen effector molecules is important for genetic engineering strategies to control mosquito-borne diseases. Adult female salivary glands are involved in pathogen transmission human hosts target sites molecules. The Aedes aegypti 30K a b genes expressed exclusively adult transcribed divergently from start separated by 263 nucleotides. intergenic, 5'- 3'-end untranslated regions both sufficient express simultaneously two...

In 2006, we reported a mariner (Mos1)-transformed Aedes aegypti line, Carb77, which was highly resistant to dengue-2 virus (DENV2). Carb77 mosquitoes expressed DENV2-specific inverted-repeat (IR) RNA in midgut epithelial cells after ingesting an infectious bloodmeal. The IR-RNA formed double-stranded DENV2-derived RNA, initiating intracellular antiviral interference (RNAi) response. However, stopped expressing the 17 generations culture and lost their DENV2-refractory phenotype. current...

Background Vector competence of Aedes aegypti mosquitoes is a quantitative genetic trait that varies among geographic locations and different flavivirus species genotypes within species. The subspecies Ae. formosus, found mostly in sub-Saharan Africa, considered to be refractory both dengue (DENV) yellow fever viruses (YFV) compared the more globally distributed aegypti. Within Senegal, vector with collection site DENV-2 viral isolate, but knowledge about interaction West African...

Aedes aegypti is the primary mosquito vector of dengue viruses (DENV; serotypes 1-4). Human-mosquito transmission cycles maintain DENV during epidemics but questions remain regarding how these survive when human infections and abundance are minimal. mosquitoes can transmit within population through two alternate routes: vertical venereal (VT VNT, respectively). We tested efficiency VT VNT in a genetically diverse laboratory (GDLS) strain Ae. orally infected with DENV2 (Jamaica 1409)....

Arthropod-borne viruses (arboviruses) infect mosquito salivary glands and then escape to saliva prior virus transmission. Arbovirus transmission from mosquitoes can be modulated by gland infection barriers (SGIBs) (SGEBs). We determined the influence of SGIBs SGEBs estimating quantitative genetic contributions Aedes aegypti half-sib families (Mapastepec, Mexico) infected with three dengue 2 (DENV2), two chikungunya (CHIKV), Zika (ZIKV) genotypes. titer per at seven days post-infection...

The yellow fever mosquito Aedes aegypti is a major vector of arthropod-borne viruses, including dengue, chikungunya, and Zika viruses. A novel approach to mitigate arboviral infections generate mosquitoes refractory infection by overexpressing antiviral effector molecules. Such an requires mechanism spread these effectors through population, for example, using CRISPR/Cas9-based gene drive systems. Critical the design single-locus autonomous that selected genomic locus amenable both...

Abstract Transgenic Aedes aegypti were engineered to express a virus‐derived, inverted repeat (IR) RNA in the mosquito midgut trigger interference (RNAi) and generate resistance dengue virus type 2 (DENV2) vector. Here we characterize genotypic phenotypic stabilities of one line, Carb77, between generations G 9 17 . The anti‐DENV2 transgene was integrated at single site within noncoding region genome. phenotype strong until 13 suppressed replication different DENV2 genotypes. From 14 –G...

Abstract Alphavirus transducing systems (ATSs) are alphavirus‐based tools for expressing genes in insects. Here we describe an ATS (5′dsMRE16ic) based entirely on Sindbis MRE16 virus. GFP expression was used to characterize alimentary tract infections and dissemination three Culicine two Lepidopteran species. Following per os infection, 5′dsMRE16ic‐EGFP efficiently infected Aedes aegypti Culex tritaeniorhynchus , but not pipiens . Ae. clearly showed accumulation of green fluorescent protein...

Epidemic dengue has emerged throughout the tropical world. In continued absence of a vaccine against virus (DENV), mosquito vector surveillance and control programs are essential to reduce human infections. An effective test detect DENV in infected mosquitoes would be valuable addition effort. We investigated detection Aedes aegypti using commercially available non-structural protein 1 (NS1) ELISA kit (Platelia Dengue NS1 Ag), by reverse transcription-polymerase chain reaction (RT-PCR)...

Transgenic mosquitoes generated by transposable elements (TEs) often poorly express transgenes owing to position effects. To avoid these effects, the ΦC31 site-directed recombination system was used insert into a locus favourable for gene expression in Aedes aegypti. We describe phenotypes of mariner Mos1 TE and transgenic expressing enhanced green fluorescent protein (EGFP) reporter midguts blood-fed females. Mosquitoes nine TE-generated lines [estimated transformation frequency (TF): 9.3%]...

Chikungunya virus (CHIKV) is a medically important mosquito-borne transmitted to humans by infected Aedes (Stegomyia) species. In 2013–2014, Ae. aegypti CHIKV in the Caribbean and 2005–2006, albopictus on La Réunion Island (Indian Ocean basin). LR2006 OPY1 from epidemic was associated with mutation (E1:A226V) viral E1 glycoprotein that enhanced transmission albopictus. R99659 outbreak did not have E1:A226V mutation. Here, we analyzed salivary glands saliva of strains New Jersey, Florida,...

We tested a nootkatone product for insecticide activity against the most prominent vectors of Zika virus (ZIKV), Aedes aegypti, and albopictus. permethrin-resistant (PERM-R) Vergel strain A. aegypti permethrin-susceptible (PERM-S) New Orleans to determine if resistance affected their susceptibility nootkatone. Bottle bioassays showed that PERM-S (New Orleans) was more susceptible than confirmed strain, Vergel. The albopictus ATM-NJ95 known Coatzacoalcos permethrin unknown but proved be...