Project description:Pan-viral DNA array (PVDA) and high-throughput sequencing (HTS) are useful tools to identify novel virus of emerging diseases. However, both techniques have difficulties to identify viruses in clinical samples because of host genomic DNA (hgDNA) contamination. Both propidium monoazide (PMA) and ethidium bromide monoazide (EMA) have the capacity to bind free DNA but are cell membrane-impermeable and thus are unable to bind protected DNA and RNA such as viral genomic material. DNA modified by EMA or PMA is not amplifiable by polymerase. In order to assess the capacity of EMA or PMA to lower hgDNA, serum or lung tissue homogenates were spiked with porcine reproductive and respiratory virus (PRRSV) and were processed with different combination of treatment: with or without ultracentrifugation and incubation with or without different concentration of EMA or PMA. PVDA and HTS were used to evaluate the capacity of both techniques to detect the presence of PRRSV from each sample. Negative results were obtained by PVDA and low amount of PRRSV specific reads were obtained by HTS with untreated samples or samples treated only by ultracentrifugation. An increase capacity of PRRSV detection was observable by PVDA in EMA and PMA treated samples but PVDA best results were obtained following PMA treatment, with or without ultracentrifugation. HTS sensitivity was also improved by a treatment with EMA or PMA, but the number of reads was significantly higher in PMA treated samples. These results support the use of PMA as a treatment to increase sensitivity of PVDA and HTS.
Project description:Pan-viral DNA array (PVDA) and high-throughput sequencing (HTS) are useful tools to identify novel virus of emerging diseases. However, both techniques have difficulties to identify viruses in clinical samples because of host genomic DNA (hgDNA) contamination. Both propidium monoazide (PMA) and ethidium bromide monoazide (EMA) have the capacity to bind free DNA but are cell membrane-impermeable and thus are unable to bind protected DNA and RNA such as viral genomic material. DNA modified by EMA or PMA is not amplifiable by polymerase. In order to assess the capacity of EMA or PMA to lower hgDNA, serum or lung tissue homogenates were spiked with porcine reproductive and respiratory virus (PRRSV) and were processed with different combination of treatment: with or without ultracentrifugation and incubation with or without different concentration of EMA or PMA. PVDA and HTS were used to evaluate the capacity of both techniques to detect the presence of PRRSV from each sample. Negative results were obtained by PVDA and low amount of PRRSV specific reads were obtained by HTS with untreated samples or samples treated only by ultracentrifugation. An increase capacity of PRRSV detection was observable by PVDA in EMA and PMA treated samples but PVDA best results were obtained following PMA treatment, with or without ultracentrifugation. HTS sensitivity was also improved by a treatment with EMA or PMA, but the number of reads was significantly higher in PMA treated samples. These results support the use of PMA as a treatment to increase sensitivity of PVDA and HTS. A non specific DNA probe is used as a negative hybridization control. Also, specifics probes targeting pUC19 plasmid DNA is used as a DNA array positive control as well as a localization control. Finally, there are 34 probes of 70 nucleotides spotted in duplicate were selected to target PRRSV conserved regions. A total of 80 different tests were done by DNA array in order to evaluate different treatments conditions with EMA or PMA, with or without ultracentrifugation. A total of 58 samples were tested on specific lung tissue homogenates spiked with different concentration of PRRSV and 12 samples were serum samples spiked with one concentration of PRRSV. Finally. A total of six samples
Project description:Large White and Meishan pigs were either non-treated or injected with mammalian 1-24 ACTH (Immediate Synachten, Novartis France) at the dose of 250 µg per animal. Pigs were sacrificed either immediately after capture from their home cage (non-treated animals) or 1 hour following ACTH injection. Adrenal glands were immediately collected from pigs and frozen on dry ice and then stored at -80°C until RNA isolation. Keywords: stress response, adrenal, gene expression, pig
Project description:Large White and Meishan pigs were either non-treated or injected with mammalian 1-24 ACTH (Immediate Synachten, Novartis France) at the dose of 250 µg per animal. Pigs were sacrificed either immediately after capture from their home cage (non-treated animals) or 1 hour following ACTH injection. Adrenal glands were immediately collected from pigs and frozen on dry ice and then stored at -80°C until RNA isolation. Keywords: stress response, adrenal, gene expression, pig 47 samples
Project description:In this study, we applied the isobaric tags for relative and absolute quantitation (iTRAQ) technique to detect alterations in the proteomic profile of the jejunal mucosa using a porcine model in which piglets were offered the protein-limited (PL) diet. Protein identification and quantification for iTRAQ experiments were performed using ProteinPilot (v4.0.8085) software. The LC-MS/MS data were searched against the UniProtKB (sus scrofa). To minimize the false discovery rate (FDR), a threshold for protein identification was applied, with the confident value > 95% (amount to the confident value “unused ProtScore” > 1.3 in ProteinPilot software), and at least one unique peptide was considered for protein identification. Proteins that were quantified with fold change > 2.0 were considered to be differentially expressed proteins. We identified 5275 proteins, 202 of which were differentially expressed. Furthermore, we adopted function annotation analysis of all identified proteins and function enrichment analysis of all differentially expressed proteins to explore more meaningful proteins and pathways.