Project description:Dengue and Zika are closely related members of the Flaviviridae family of positive, single-stranded RNA viruses and are of global clinical importance. These viruses utilize an 11kb RNA genome for translation and replication, and much remains to be learnt about how the entire genome folds to enable virus function. Here, we performed high throughput RNA secondary structure and pair-wise interaction mapping on four dengue serotypes and four Zika strains within their virus particles. We identified structures that are associated with translation pausing, and are evolutionary conserved by integrating synonymous mutation rates into our analysis. Genome-wide interaction mapping revealed alternative structures, as well as extensive long-range RNA interactions – including the known circularization signals– within the virus particles. Many of these long-range interactions are conserved across the viruses and/or clustered into “hubs” that are shown to be functionally important. This comprehensive structural resource of dengue and Zika viruses reveals that viral genome organization is much more complex than previously appreciated and deepens our understanding of the molecular basis for viral pathogenesis.
Project description:We used data independent acquisition (DIA) mass spectrometry (MS) to profile ~800 proteinsfrom 122 serum samples Dengue or Zika Trinidadian patients. Two time points were collectedper patient. The DIA MS data were matched against a spectral library generated from high pH/low pH separated pooled serum samples.
Project description:Dengue and Zika are two mosquito-borne diseases of great concern, affecting mainly the tropical and subtropical regions worldwide. The arrival of Zika virus (ZIKV) in dengue virus (DENV) endemic areas imposed challenges for differential diagnosis and the development of candidate vaccines. The use of peptides has shown great potential to achieve these goals. We aimed to identify the linear epitope profile recognized by the serum samples of dengue and Zika patients in the E and NS1 proteins of DENV and ZIKV to select peptides with the potential for the development of diagnostic tests and vaccines. Analysis of a peptide microarray platform with serum samples of dengue and Zika patients demonstrated that the epitopes were evenly distributed across the entire viral proteins, showing no preference for particular regions. However, several epitopes were within epitope hot spots constituted by clusters of peptides recognized in more than 30% of the sub-arrays analyzed with individual or pools of serum samples. The serum samples of dengue and Zika patients showed a high level of cross-reaction for epitopes in the DENV and ZIKV proteins. Analysis of an additional peptide microarray platform containing selected peptides based on the results of the first screening showed that three peptides (DENV: TQGEPSLNEEQDKRF and TQTVGPWHLGKLEID; ZIKV: LELDPPFGDSYIVIG), highly specific for their cognate viruses (p<0.05), were within the epitope hot spots; however, these peptides showed low detection rates (32.5, 35.0, and 28.6%, respectively). We also found two peptides (DENV: WEVEDYGFGVFTTNI and LELDFDLCEGTTVVV) in the epitope hot spots detected by both dengue and Zika patients with similarly high rates (arbitrary detection rate cut-off threshold of ≥40%). The epitope hot spots harbor several immunodominant epitopes recognized by a higher number of individuals when compared to the 15 aa sequence peptides. Therefore, the entire epitope hot spots, spanning up to ~30 aa, would have more potential than peptides of only 15 aa to serve as antigens in diagnostic tests and vaccine developments.
Project description:Dengue and Zika are two mosquito-borne diseases of great concern, affecting mainly the tropical and subtropical regions worldwide. The arrival of Zika virus (ZIKV) in dengue virus (DENV) endemic areas imposed challenges for differential diagnosis and the development of candidate vaccines. The use of peptides has shown great potential to achieve these goals. We aimed to identify the linear epitope profile recognized by the serum samples of dengue and Zika patients in the E and NS1 proteins of DENV and ZIKV to select peptides with the potential for the development of diagnostic tests and vaccines. Analysis of a peptide microarray platform with serum samples of dengue and Zika patients demonstrated that the epitopes were evenly distributed across the entire viral proteins, showing no preference for particular regions. However, several epitopes were within epitope hot spots constituted by clusters of peptides recognized in more than 30% of the sub-arrays analyzed with individual or pools of serum samples. The serum samples of dengue and Zika patients showed a high level of cross-reaction for epitopes in the DENV and ZIKV proteins. Analysis of an additional peptide microarray platform containing selected peptides based on the results of the first screening showed that three peptides (DENV: TQGEPSLNEEQDKRF and TQTVGPWHLGKLEID; ZIKV: LELDPPFGDSYIVIG), highly specific for their cognate viruses (p<0.05), were within the epitope hot spots; however, these peptides showed low detection rates (32.5, 35.0, and 28.6%, respectively). We also found two peptides (DENV: WEVEDYGFGVFTTNI and LELDFDLCEGTTVVV) in the epitope hot spots detected by both dengue and Zika patients with similarly high rates (arbitrary detection rate cut-off threshold of ≥40%). The epitope hot spots harbor several immunodominant epitopes recognized by a higher number of individuals when compared to the 15 aa sequence peptides. Therefore, the entire epitope hot spots, spanning up to ~30 aa, would have more potential than peptides of only 15 aa to serve as antigens in diagnostic tests and vaccine developments.
Project description:Zika virus (ZIKV) and dengue virus (DENV) are members of the Flaviviridae family of RNA viruses and cause severe disease in humans. ZIKV and DENV share over 90% of their genome sequences, however the clinical features of Zika and dengue infections are very different reflecting tropism and cellular effects. Here, we used simultaneous RNA sequencing and ribosome footprinting to define the transcriptional and translational dynamics of ZIKV and DENV infection in human neuronal progenitor cells (hNPCs). The gene expression data showed induction of aminoacyl tRNA synthetases (ARS) and the translation-activating PIM1 kinase indicating an increase in RNA translation capacity. The data also reveal activation of different cell stress reponses, with ZIKV triggering a BACH1/2 redox program, and DENV activating the ETF/CHOP endoplasmatic reticulum (ER) stress program. The RNA translation data highlight activation of polyamine metabolism through changes in key enzymes and their regulators. This pathway is needed for eIF5A hypusination and has been implicated viral translation and replication. Concerning the viral RNA genomes, ribosome occupancy readily identifies highly translated open reading frames and a novel upstream ORF (uORF) in the DENV genome. Together, our data highlight both the cellular stress response and also the activation of RNA translation and polyamine metabolism during DENV and ZIKV infection.
Project description:Viral pathogens are an ongoing threat to public health worldwide. Dissecting their dependence on host biosynthetic pathways could lead to effective antiviral therapies. To define how entero- and flaviviruses redirect host ribosomes to synthesize viral proteins and disable host protein production, we performed proteomic analysis of lysates and isolated polysomes from human Huh7 cells infected with either polio, zika or dengue viruses. We find that infection remodels polysome composition along similar principles, without major changes to core ribosome stoichiometry. These viruses use different strategies to evictfrom polysomes a common set of translation initiation and RNA surveillance factors while recruiting host machineries specifically required for viral biogenesis. We also find that both zika and dengue utilize the collagen prolyl-hydroxylation machinery to mediate co-translational modification of conserved prolines in the viral polyprotein. Our findings show how RNA viruses co-opt polysome modularity and establish a powerful strategy to identify targets for selective antiviral interventions.
Project description:In this study, 10x Chromium technology was applied to quantify transcripts from single-cell nuclei of adult male and female brain of Aedes aegypti, a medically important mosquito vector that transmits yellow fever, dengue, chikungunya, and Zika viruses to humans.
Project description:Flaviviruses, including Dengue and Zika, are widespread human pathogens; however, no broadly active therapeutics exist to fight infection. Recently, remodeling of endoplasmic reticulum (ER) proteostasis by pharmacologic regulators, such as compound 147, was shown to correct pathologic ER imbalances associated with protein misfolding diseases. Here, we establish a new activity of compound 147 as an effective host-centered antiviral agent against flaviviruses. Compound 147 reduces infection by attenuating the infectivity of secreted virions without causing toxicity in host cells. 147 is a preferential activator of the ATF6 pathway of the ER unfolded protein response, which requires targeting of cysteine residues primarily on protein disulfide isomerases (PDIs). We find that the antiviral activity of 147 is independent of ATF6 induction but does require modification of reactive thiols on protein targets. Targeting PDIs and additional non-PDI targets using RNAi and other small molecule inhibitors was unable to recapitulate the antiviral effects, suggesting a unique polypharmacology may mediate the activity. Importantly, 147 can impair infection of multiple strains of Dengue and Zika virus, indicating that it is suitable as a broad-spectrum antiviral agent.
Project description:The Virochip microarray (version 5.0, Viro5AGL-60K platform) was used to verify the presence or absence of Chikungunya virus in RNA extracts from asymptomatic blood donors located in Puerto Rico.