Project description:Background: Salmonid species have followed markedly divergent evolutionary trajectories in their interactions with sea lice. While sea lice parasitism poses significant economic, environmental, and animal welfare challenges for Atlantic salmon (Salmo salar) aquaculture, coho salmon (Oncorhynchus kisutch) exhibit near-complete resistance to sea lice, achieved through a potent epithelial hyperplasia response leading to rapid louse detachment. The molecular mechanisms underlying these divergent responses to sea lice are unknown. Results: We characterised the cellular and molecular responses of Atlantic salmon and coho salmon to sea lice using single-nuclei RNA sequencing. Juvenile fish were exposed to copepodid sea lice (Lepeophtheirus salmonis), and lice-attached pelvic fin and skin samples were collected 12h, 24h, 36h, 48h, and 60h after exposure, along with control samples. Comparative analysis of control and treatment samples revealed an immune and wound-healing response that was common to both species, but attenuated in Atlantic salmon, potentially reflecting greater sea louse immunomodulation. Our results revealed unique but complementary roles of three layers of keratinocytes in the epithelial hyperplasia response leading to rapid sea lice rejection in coho salmon. Our results suggest that basal keratinocytes direct the expansion and mobility of intermediate and, especially, superficial keratinocytes, which eventually encapsulate the parasite. Conclusions: Our results highlight the key role of keratinocytes in coho salmon’s sea lice resistance, and the diverged biological response of the two salmonid host species when interacting with this parasite. This study has identified key pathways and candidate genes that could be manipulated using various biotechnological solutions to improve Atlantic salmon sea lice resistance.
Project description:The mechanisms of action of compound 8 in Mycobacterium marinum although it inhibits the secretion of the bacteria. In this experiment, we aim to investigated the effect of compound 8 on the global gene expression of Mycobacterium marinum
Project description:We identify a putative link between miR-126 knockdown and neuroactive ligand and notch signalling pathways in uninfected and Mycobacterium marinum infected zebrafish embryos.
Project description:Mycobacteria infect macrophages that aggregate with additional macrophages and lymphocytes to form granulomas. We have used a functional genomics approach to identify immune response genes expressed during granuloma formation in Mycobacterium marinum-infected transparent zebrafish larvae where individual infection steps can be viewed in real time. We assessed RNA expression profiles from zebrafish larvae that were either infected with Mycobacterium marinum or mock-infected. Zebrafish infections were performed at 1 day post-fertilization (dpf), and samples were derived from pools of 6dpf zebrafish larvae. Keywords: host response to infection
Project description:Mycobacteria infect macrophages that aggregate with additional macrophages and lymphocytes to form granulomas. We have used a functional genomics approach to identify immune response genes expressed during granuloma formation in Mycobacterium marinum-infected transparent zebrafish larvae where individual infection steps can be viewed in real time. We assessed RNA expression profiles from zebrafish larvae that were either infected with Mycobacterium marinum, mock-infected, or uninfected. Zebrafish infections were performed at 1 day post-fertilization (dpf), and samples were derived from pools of 6dpf zebrafish larvae. Keywords: host response to infection
Project description:Mycobacterium marinum infection in zebrafish (Danio rerio) has been widely used to study human tuberculosis because the bacteria causing these two diseases are close relatives. We studied the zebrafish immune response to M. marinum infection through a whole-genome level transcriptome analysis. As expected based on the literature, our results showed the induction of genes coding proteins associated to immune signaling, cell migration and acute phase response indicating that the immune response to M. marinum infection in zebrafish is similar than the response to tuberculosis causing Mycobacterium tuberculosis in humans.
Project description:Related surrogate species are often used to study the molecular basis of pathogenicity of a pathogen on the basis of a shared set of biological features generally attributable to a shared core genome consisting of orthologous genes. An important and understudied aspect, however, is the extent to which regulatory features affecting the expression of such shared genes are present in both species. Here we report on an analysis of whole transcriptome maps for an important member of the TB complex Mycobacterium bovis and a closely related model organism for studying mycobacterial pathogenicity Mycobacterium marinum. Predict transcription start site
Project description:Related surrogate species are often used to study the molecular basis of pathogenicity of a pathogen on the basis of a shared set of biological features generally attributable to a shared core genome consisting of orthologous genes. An important and understudied aspect, however, is the extent to which regulatory features affecting the expression of such shared genes are present in both species. Here we report on an analysis of whole transcriptome maps for an important member of the TB complex Mycobacterium bovis and a closely related model organism for studying mycobacterial pathogenicity Mycobacterium marinum.
Project description:Understanding the regulatory roles of small RNAs (sRNAs) in Mycobacterium marinum is crucial for elucidating its pathogenesis. Here, we present transcriptome profiles of M. marinum strains with deletions and completions of sRNA B11. Through RNA sequencing analysis, we identified significant alterations in gene expression patterns between the B11-deleted and completed strains.