Abstract
Salmon lice (Lepeophtheirus salmonis) are parasitic copepods, living mainly on Atlantic salmon and leading to large economical losses in aquaculture every year. Due to the emergence of resistances to several drugs, alternative treatments are developed, including treatment with hydrogen peroxide, freshwater or thermal treatment. The present study gives a first overview of the thermotolerance and stress response of salmon lice. Sea lice nauplii acclimated to 10 °C can survive heat shocks up to 30 °C and are capable of hardening by a sublethal heat shock. We searched in the genome for heat shock protein (HSP) encoding genes and tested their inducibility after heat shock, changes in salinity and treatment with hydrogen peroxide, employing microfluidic qPCRs. We assessed 38 candidate genes, belonging to the small HSP, HSP40, HSP70 and HSP90 families. Nine of these genes showed strong induction after a non-lethal heat shock. In contrast, only three and two of these genes were induced after changes in salinity and incubation in hydrogen peroxide, respectively. This work provides the basis for further work on the stress response on the economically important parasite L. salmonis.
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Acknowledgements
We want to thank Heidi Kongshaug, Brigitte Schöpel, Ingrid Hennings and Luisa Falkenthal for help in the lab. Lars Hamre and Per Gunnar Espedal are thanked for maintaining the sea lice strains and organization of the wet lab. This research has been funded by the Research Council of Norway, SFI-Sea Lice Research Centre, grant number 203513/O30 and the Norwegian Seafood Research Fund – FHF (Fiskeri- og havbruksnæringens Forskningsfond). Project: OSMO-Lus, grant number 901208.
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Borchel, A., Komisarczuk, A.Z., Rebl, A. et al. Systematic identification and characterization of stress-inducible heat shock proteins (HSPs) in the salmon louse (Lepeophtheirus salmonis). Cell Stress and Chaperones 23, 127–139 (2018). https://doi.org/10.1007/s12192-017-0830-9
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DOI: https://doi.org/10.1007/s12192-017-0830-9