Project description:Eukaryotic cells recognize intracellular pathogens through pattern recognition receptors, including sensors of aberrant nucleic acid structures. Sensors of double-stranded RNA (dsRNA) are known to detect replication intermediates of RNA viruses. It has been suggested that annealing of mRNA from symmetrical transcription of both top and bottom strands of DNA virus genomes can produce dsRNA during infection. Supporting this hypothesis, nearly all DNA viruses encode inhibitors of dsRNA-recognition pathways. However, direct evidence that DNA viruses produce dsRNA is lacking. Contrary to dogma, we show that the nuclear-replicating DNA virus adenovirus (AdV) does not produce detectable levels of dsRNA during infection. In contrast, abundant dsRNA is detected within the nucleus of cells infected with AdV mutants that lack the virus-directed ubiquitin ligase required for efficient processing of viral RNA. In the presence of nuclear dsRNA, the cytoplasmic dsRNA sensor PKR is relocalized and activated within the nucleus. Accumulation of viral dsRNA occurs in the late phase of infection, when unspliced viral transcripts form intron/exon base pairs between top and bottom strand transcripts. We propose that DNA viruses actively promote efficient splicing and mRNA processing to limit dsRNA formation, thus avoiding detection and restriction by host nucleic acid sensors.

2021-07-15 | GSE179388 | GEO

Determination of dsRNA interactome upon Sindbis virus infection in human cells identifies SFPQ as a critical proviral factor

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.

2024-05-22 | PXD024554 | Pride

Next Generation Sequencing Facilitates Quantitative Analysis of yeast cells lacking either M-2 dsRNA or both L-A-lus and M-2 dsRNA viruses

Project description:Here we determine the impact upon the loss of M-2 dsRNA alone and both L-A-lus along with M-2 on the host S. cerevisiae transcriptional changes. By performing profiling of the whole transcriptomes, we determined 486 genes differentially expressed after curing of yeast cells from M-2 dsRNA and 715 genes affected by the elimination of both M-2 and L-A-lus dsRNAs.

2017-07-26 | GSE100290 | GEO

RNA-seq of fibroblasts from two bat species stimulated by dsRNA to trigger antiviral response

Project description:Dermal fibroblasts from megabat and microbat, stimulated with dsRNA (poly(I:C)) and controls. Bats can harbor some of the most deadliest viruses to humans while rarely displaying pathogenicity themselves. To study their innate immune response - the expression program that is initiated once a pathogen is senseds, we stimulated dermal fibroblast cells from two species (Rousettus aegyptiacus and Pipistrellus kuhlii) for four hours with dsRNA - a viral RNA mimic that triggers a rapid innate immune response. Subsequently, we profiled the response using bulk RNA-seq.

2022-10-01 | E-MTAB-10870 | biostudies-arrayexpress

Single-Cell RNA-seq of bat and human fibroblasts stimulated by dsRNA to trigger antiviral response

Project description:Dermal fibroblasts from bat and human, stimulated with dsRNA (poly(I:C)) and controls. Bats can harbor some of the most deadliest viruses to humans while rarely displaying pathogenicity themselves. To study the transcriptional divergence and cell-to-cell variability of their innate immune response - the expression program that is initiated once a pathogen is sensed, we stimulated dermal fibroblast cells from Rousettus aegyptiacus and from human for four hours with dsRNA - a viral RNA mimic that triggers a rapid innate immune response. Subsequently, we profiled the response using scRNA-seq.

2022-10-01 | E-MTAB-11056 | biostudies-arrayexpress

Umbelopsis ramanniana AG strain:AG

Project description:Umbelopsis ramanniana AG strain:AG Genome sequencing and assembly

| PRJNA196032 | ENA