Project description:Infections with bovine viral diarrhea virus (BVDV) contribute significantly to health-related economic losses in the beef and dairy industries and are widespread throughout the world. Severe acute BVDV infection is characterized by a gastrointestinal (GI) inflammatory response. The mechanism of inflammatory lesions caused by BVDV remains unknown. The interstitial cells of Cajal (ICC) network plays a pivotal role as a pacemaker in the generation of electrical slow waves for GI motility, and it is crucial for the reception of regulatory inputs from the enteric nervous system. The present study investigated whether ICC were a good model for studying GI inflammatory lesions caused by BVDV infection. Primary ICC were isolated from the duodenum of Merino sheep. The presence of BVDV was detected in ICC grown for five passages after BVDV infection, indicating that BVDV successfully replicated in ICC. After infection with BVDV strain TC, the cell proliferation proceeded slowly or declined. Morphological changes, including swelling, dissolution, and formation of vacuoles, of ICC were observed, pointing to quantitative, morphological and functional changes of ICC. Therefore, RNA sequencing (RNA-Seq) was performed to investigate differentially expressed genes (DEGs) in BVDV-infected ICC and to further explore the molecular mechanism of underlying quantitative, morphological and functional changes of ICC. Eight hundred six genes were differentially expressed upon BVDV infection, of which 538 genes were upregulated and 268 genes were downregulated. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the 806 DEGs were significantly enriched in 27 pathways, including cytokine-cytokine receptor interaction, interleukin (IL)-17 signaling, mitogen-activated protein kinase (MAPK) signaling pathway. Finally, 21 DEGs were randomly selected, and the relative repression levels of these genes were tested using the quantitative real-time PCR (qRT-PCR) to validate the RNA-Seq results. The results showed that the related expression levels of 21 DEGs were similar to RNA-Seq. This study is the first to establish a new infection model for investigating GI inflammatory lesions induced by BVDV infection.
Project description:The impact of late-term fetal bovine viral diarrhea virus (BVDV) transient infections (TI) on fetal growth and methylome was examined by inoculating pregnant heifers with a noncytopathic (ncp) type 2 BVDV suspended in media or media alone (sham-inoculated controls) on day 175 of gestation to generate TI (n=11) and control heifer calves (n=12). Blood samples were collected at birth. White blood cells (WBC) were separated for DNA extraction. Fetal infection in calves was confirmed by positive virus serum neutralizing antibody titers at birth and control calves were seronegative. Both control and TI calves were negative for BVDV RNA in WBCs by RT-PCR. DNA methyl seq analysis of WBC DNA demonstrated 2,349 differentially methylated cytosines (p≤0.05) including 1,277 hypomethylated cytosines, 1.072 hypermethylated cytosines, 84 differentially methylated regions based on CpGs in promoters and 89 DMRs based on CpGs in exons of TI WBC DNA compared to controls. Fetal BVDV infection during late gestation resulted in epigenomic modifications predicted to affect fetal and organ development pathways suggesting potential consequences for postnatal growth and health of TI cattle.
Project description:Small non-coding RNAs have emerged as key players in modulation of viral infection. A unique example is the critical dependence of hepatitis C virus (HCV) on the liver-specific microRNA (miRNA), miR-122, which has surfaced as therapeutic target. Here, we used crosslinking immunoprecipitation (CLIP) of the Argonaute (AGO) protein to characterize strengths and specificities of miRNA interactions across 15 viral genomes. Intriguingly, replication of pestiviruses, which are major threats to milk and meat industry, critically depends on cellular miR-17 and let-7 interactions with the viral 3âUTR. Like HCV, miRNA binding enhanced translation and prevented viral RNA degradation. On the cellular transcriptome, pestiviral miR-17 sequestration in vitro and ex vivo conferred reduced AGO binding and functional mRNA de-repression for miR-17 targets. These findings generalize the concept of RNA virus dependence on cellular miRNAs, highlight such interactions as therapeutic targets, and connect functional regulation of the transcriptome in primary cells to miRNA sequestration. Several subseries of analyses were performed. For each sample, subseries to which it belongs are indicated. In the âVirus AGO-CLIPâ subseries, AGO-CLIP was performed on cells infected with virus as indicated. Processed reads were aligned to the host genome (hg18 or BosTau7) and to the respective viral genome. The primary data of interest from this subseries concerns AGO binding to viral RNA, and is given as processed data file âTable S1â. In the âVirus AGO-CLIP: BVDV vs. Mockâ subseries, AGO-CLIP was performed on four replicates each of BVDV and mock infected MDBK cells. CLIP reads aligned to BosTau7 were clustered, and differential analysis was performed on binding to each cluster. In addition, differential analysis of AGO bound miRNAs was performed. The associated data is given as processed data file âTable S3 and S4â. In the âAGO-CLIP: tinyLNA-17 vs. Mockâ AGO-CLIP was performed on four replicates each of tinyLNA-17 and mock treated MDBK cells. CLIP reads aligned to BosTau7 were clustered, and differential analysis was performed on binding to each cluster. The associated data is given as processed data file âTable S5â. In the âRNA-seq: BVDV vs. Mockâ subseries, mRNA-seq was performed on two replicates each of MDBK cells infected with different biotypes of BVDV or with miR-17 seed site mutant BVDV. The latter (incl. mock controls) were trans-complemented with the corresponding mutated miR-17. Differential gene expression analysis was performed between selected conditions. The associated data is given as processed data file âTable S6â.
Project description:Grouper is an important commercial maricultural fish, which suffer viral nervous necrosis (VNN) disease at the larval and juvenile stages, but the changes of transcriptomics and proteomics during viral infection remain unknown. In this study, we applied RNA-seq and label-free mass spectrum for the first time to depict the map of transcriptomics and proteomics in non-infected, susceptible-infected and tolerate-infected grouper in larval stage. Further analyses showed that the transcriptome and proteome change dramatically among 3 distinct groups, indicating that different immune response for infected and perststent grouper in larval stage. These valuable transcriptomics and proteomics datasets enable the investigation of molecular mechanism in nervous necrosis (VNN) virus infection, thus helps the further development of molecular breeding and marine fishery
Project description:SARS-CoV-2 causes the COVID-19 pandemic. It is urgent to develop disease models to dissect mechanisms regulating SARS-CoV-2 infection. Here, we derive airway organoids from human pluripotent stem cells (hPSC-AOs). The hPSC-AOs, particularly ciliated-like cells, are permissive to SARS-CoV-2 infection. Using this platform, we perform a high content screen and identify GW6471, which blocks SARS-CoV-2 infection. GW6471 can also block infection of the B.1.351 SARS-CoV-2 variant. RNA-seq analysis suggests that GW6471 blocks SARS-CoV-2 infection at least in part by inhibiting HIF1α, which is further validated by chemical inhibitor and genetic perturbation targeting HIF1α. Metabolic profiling identifies decreased rates of glycolysis upon GW6471 treatment, consistent with transcriptome profiling. Finally, xanthohumol, 5-(Tetradecyloxy)-2-furoic acid, and ND-646, three compounds that suppress fatty acid biosynthesis, also block SARS-CoV-2 infection. Together, a high content screen coupled with transcriptome and metabolic profiling reveals a key role of the HIF1α-glycolysis axis in mediating SARS-CoV-2 infection of human airway epithelium.
Project description:Fetal spleens were collected at days 82 and 97 of gestation following maternal infection with BVDV on day 75 of gestation. A microarray was performed on RNA -> cDNA of the splenic samples. Treatment groups consist of Controls (non-infected) and PI (persistently infected).
Project description:Transcriptional profiling by array was performed to investigate differentially expressed genes (DEGs) in BVDV-infected MDBK cells and to further explore the molecular mechanism of underlying functional changes caused by infection.
Project description:Transcriptional profiling by array was performed to investigate differentially expressed genes (DEGs) in MDBK cells infected with field strains of BVDV and to further explore the molecular mechanism of underlying functional changes caused by infection.