Project description:Transcriptomic profiling of Homarus americanus after in vivo challenge with White Spot Syndrome Virus Two condition (control and infected) time series experiment; Biological replicates: 3 x 6 h control, 3 x 168 h control, 4 x 6 h infected, 4 x 12 h infected, 4 x 24 h infected, 4 x 48 h infected, 4 x 96 h infected, 4 x 168 h infected
Project description:Spot 42 was discovered in Escherichia coli nearly 40 years ago as an abundant, small and unstable RNA. Its biological role remained obscure until it was shown to cause discoordinate expression of the galactose operon (gal operon). Recently Spot 42 has also been implicated in having broader roles in the central and secondary metabolism. Spot 42 is encoded by the spf gene. The gene is ubiquitous in the Vibrionaceae family of gamma-proteobacteria, which includes a number of serious pathogens of humans and animals, including the infamous Vibrio cholerae. One member of this family, Aliivibrio salmonicida, causes cold-water vibriosis in farmed Atlantic salmon. Its genome encodes Spot 42 with 84 % identity to E. coli Spot 42 (spf). We generated a A. salmonicida spf deletion mutant. We then and used microarray and Northern blot analyses to monitor global effects on the transcriptome in order to provide insights into the biological roles of Spot 42 in this bacterium. In the presence of glucose we found a surprisingly large number of ≥2× differentially expressed genes, and several major cellular processes were affected, such as carbohydrate metabolism and transport, motility and chemotaxis, iron homeostasis and quorum sensing. A gene encoding a pirin-like protein (VSAL_I1200) showed an on/off expression pattern in the presence/absence of Spot 42, which suggests that Spot 42 plays a key regulatory role in the central metabolism by regulating the switch between fermentation and respiration. Interestingly, in a global search we discovered a sRNA, named VSsrna24, which is encoded immediately downstream of spf. This new sRNA has an expression pattern opposite to that of Spot 42, and its expression is highly dependent on glucose. Our hypothesis is that this novel sRNA works in concert with Spot 42 to regulate carbohydrate metabolism and uptake.
Project description:Understanding the molecular mechanisms of feed efficiency is an important step toward sustainability of salmonids aquaculture. In this study, the liver and white muscle proteomes of efficient (EFF) and inefficient (INEFF) Chinook salmon (Oncorhynchus tshawytscha) farmed in sea water were investigated by liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach. In total, 2,746 liver and 702 white muscle quantified proteins were compared between 21 EFF and 22 INEFF fish. Protein synthesis was enriched in both liver and white muscle of the EFF group while conversely, pathways related to protein degradation (amino acid catabolism and proteolysis, respectively) were the most affected processes in the liver and white muscle of INEFF fish. The SOM in the INEFF group was significantly higher than EFF fish showing INEFF fish probably was the dominant group. The INEFF group (dominant) suffered stress and shifted to consume energy through protein catabolism. As the first study, the results provide a preliminary picture of the fundamental molecular landscape of feed efficiency in Chinook salmon farmed in sea water
Project description:Profiles of gene expression in hepatopancreas isolated from shrimp experimentally infected with White Spot Syndrome Virus were compared to those of un-infected controls Keywords: response to viral disease Two groups of eight shrimp were compared in terms of hepatopancreas gene expression, 40 hours after challenge with White Spot Syndrome Virus
