Unknown,Transcriptomics,Genomics,Proteomics

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Differentiating size-dependent responses of juvenile pink salmon (Oncorhynchus gorbuscha) to sea lice (Lepeophtheirus salmonis) infections

ABSTRACT: Salmon infected with an ectoparasitic marine copepod, the salmon louse Lepeophtheirus salmonis, incur a wide variety of consequences depending upon host sensitivity. Juvenile pink salmon (Oncorhynchus gorbuscha) migrate from natal freshwater systems to the ocean at a young age relative to other Pacific salmon, and require rapid development of appropriate defences against marine pathogens. We analyzed the early transcriptomic responses of naïve juvenile pink salmon of sizes 0.3g (no scales), 0.7g (mid-scale development) and 2.4g (scales fully developed) to a low-level laboratory exposure with early moult stage L. salmonis. All infected size groups exhibited unique transcriptional profiles. Inflammation and inhibition of cell proliferation was identified in the smallest size class (0.3g), while increased glucose absorption and retention was identified in the middle size class (0.7g). Tissue-remodelling genes were also up-regulated in both the 0.3g and 0.7g size groups. Profiles of the 2.4g size class indicated cell-mediated immunity and possibly parasite-induced growth augmentation. Understanding a size-based threshold of resistance to L. salmonis is important for fisheries management. This work characterizes molecular responses reflecting the gradual development of innate immunity to L. salmonis between the susceptible (0.3g) and refractory (2.4g) pink salmon size classes. Six-condition experiment, 3 size groups each infected and uninfected, duplicate tanks. Biological replicates: 6 control, 6 infected for each size group. Sampled 6 days post exposure. cDNA samples with reference design (aRNA), two-color array.

ORGANISM(S): Oncorhynchus gorbuscha

SUBMITTER: Ben Koop

PROVIDER: E-GEOD-27528 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Differentiating size-dependent responses of juvenile pink salmon (Oncorhynchus gorbuscha) to sea lice (Lepeophtheirus salmonis) infections

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