Project description:<p>Despite the nuclear localization of the m6A machinery, the genomes of multiple exclusively-cytoplasmic RNA viruses, such as chikungunya (CHIKV) and dengue (DENV), are reported to be extensively m6A-modified. However, these findings are mostly based on m6A-seq, an antibody-dependent technique with a high rate of false positives. Here, we addressed the presence of m6A in CHIKV and DENV RNAs. For this, we combined m6A-seq and the antibody-independent SELECT and nanopore direct RNA sequencing techniques with functional, molecular, and mutagenesis studies. Following this comprehensive analysis, we found no evidence of m6A modification in CHIKV or DENV transcripts. Furthermore, depletion of key components of the host m6A machinery did not affect CHIKV or DENV infection. Moreover, CHIKV or DENV infection had no effect on the m6A machinery’s localization. Our results challenge the prevailing notion that m6A modification is a general feature of cytoplasmic RNA viruses and underscore the importance of validating RNA modifications with orthogonal approaches.</p>
Project description:To investigate gene specificity at the level of translation in both the human genome and viruses, we devised a high-throughput bicistronic assay to quantify cap-independent translation. We uncovered thousands of novel cap-independent translation sequences, and we provide insights on the landscape of translational regulation in both humans and viruses. We find extensive translational elements in the 3′ untranslated region of human transcripts and the polyprotein region of uncapped RNA viruses. Through the characterization of regulatory elements underlying cap-independent translation activity, we identify potential mechanisms of secondary structure, short sequence motif,and base pairing with the 18S ribosomal RNA (rRNA). Furthermore, we systematically map the 18S rRNA regions for which reverse complementarity enhances translation. Thus, we make available insights into the mechanisms of translational control in humans and viruses.
Project description:To investigate gene specificity at the level of translation in both the human genome and viruses we devised a high-throughput bicistronic assay to quantify cap-independent translation. We uncover thousands of novel cap-independent translation sequences and provide insights on the landscape of translational regulation in both human and viruses. We find extensive translational elements in the 3â untranslated region (3âUTR) of human transcripts and the polyprotein region of un-capped RNA viruses. Through the characterization of regulatory elements underlying cap-independent translation activity we identify potential mechanisms of secondary structure, short sequence motif and base-pairing with the 18S rRNA. Furthermore, we systematically map the 18S rRNA regions for which reverse complementary enhance translation. Thus we provide insights into the mechanisms of translational control in humans and viruses. high-throughput bicistronic assay for obtaining cap-independent translation measurements of 55,000 fully designed sequences in parallel using fluorescence-activated cell sorting and high-throughput DNA sequencing (FACS-seq).
Project description:Primary objectives: Characterization of the macrophage population subset that is modulated by enteric neurons
Primary endpoints: Characterization of the macrophage population subset that is modulated by enteric neurons via RNA sequencing
Project description:Transcriptome profiling of pyrethroid resistant field populations of Anopheles funestus across Uganda and neighboring Kenya from Uganda and Kenya compared to a susceptible lab strain FANG
Project description:Viruses are obligate intracellular parasites, which depend on the host cellular machineries to replicate their genome and complete their infectious cycle. Long double stranded (ds)RNA is a common viral by-product originating during RNA virus replication, which is universally sensed as a danger signal to trigger the antiviral response. As a result, viruses hide dsRNA intermediates into viral replication factories and have evolved strategies to hijack cellular proteins for their benefit. The characterization of the host factors associated to viral dsRNA and involved in viral replication remains a major challenge to develop new antiviral drugs against RNA viruses. Here, we performed anti-dsRNA immunoprecipitation followed by Mass Spectrometry to fully characterize the dsRNA interactome in Sindbis virus (SINV) infected human HCT116 cells. Among the validated factors, we characterized SFPQ (Splicing factor, proline-glutamine rich) as a new dsRNA-associated factor upon SINV infection. We proved that SFPQ is able to directly bind dsRNAs in vitro, that SFPQ association to dsRNA is independent on single-stranded (ss)RNA flanking regions in vivo and that it is able to bind the viral genome upon infection. Furthermore, we showed that either knock-down or knock-out of SFPQ reduced SINV infection in human HCT116 and SKNBE cells, suggesting that SFPQ could enhance viral replication. Overall, this study not only represents a resource to further study SINV dsRNA-associated factors upon infection but also identifies SFPQ as a new proviral dsRNA binding protein.
Project description:RNA viruses rely on cellular RNA-binding proteins (RBPs) to infect the host cell. However, the repertoire of the cellular RBPs exploited by viruses is largely unknown. Using the ‘RNA interactome capture’ method, we profiled in a proteome-wide scale the RBP-RNA interactions occurring during sindbis virus (SINV) infection. We discover that SINV affects the activity of hundreds of RBPs, essentially rewiring the host RNA-bound proteome. Such alterations do not relate to changes in protein abundance but are rather due to subcellular redistribution of RBPs and pervasive transcriptome remodelling. Strikingly, RBPs stimulated by SINV accumulate in the cytoplasmic compartments where the virus replicates and interact with viral RNA. Perturbation of these RBPs can restrict or promote infection; for example, GEMIN5 binds to key regulatory regions of SINV RNAs and inhibits viral protein expression. Importantly, we show that drug based RBP intervention may have potential as therapeutic strategy against viruses.