title: The metabolic response of marine copepods to environmental warming and ocean acidification in the absence of food.
abstract: Marine copepods are central to the productivity and biogeochemistry of marine ecosystems. Nevertheless, the direct and indirect effects of climate change on their metabolic functioning remain poorly understood. Here, we use metabolomics, the unbiased study of multiple low molecular weight organic metabolites, to examine how the physiology of Calanus spp. is affected by end-of-century global warming and ocean acidification scenarios. We report that the physiological stresses associated with incubation without food over a 5-day period greatly exceed those caused directly by seawater temperature or pH perturbations. This highlights the need to contextualise the results of climate change experiments by comparison to other, naturally occurring stressors such as food deprivation, which is being exacerbated by global warming. Protein and lipid metabolism were up-regulated in the food-deprived animals, with a novel class of taurine-containing lipids and the essential polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid and docosahexaenoic acid, changing significantly over the duration of our experiment. Copepods derive these PUFAs by ingesting diatoms and flagellated microplankton respectively. Climate-driven changes in the productivity, phenology and composition of microplankton communities, and hence the availability of these fatty acids, therefore have the potential to influence the ability of copepods to survive starvation and other environmental stressors.
authors.affiliation: Institute of Biological and Environmental Sciences, Oceanlab, University of Aberdeen, Main Street, Newburgh, Aberdeenshire AB41 6AA, UK.|Ocean Biogeochemistry and Ecosystems, National Oceanography Centre, Southampton, SO14 3ZH, UK.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Mayor
authors.affiliation: NERC Biomolecular Analysis Facility - Metabolomics Node (NBAF-B), School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK.
authors.forename: Ulf
authors.initials: U
authors.lastname: Sommer
authors.affiliation: Marine Scotland Science, Scottish Government, Marine Laboratory, 375 Victoria Road, Aberdeen AB11 9DB, UK.
authors.forename: Kathryn B
authors.initials: KB
authors.lastname: Cook
authors.affiliation: NERC Biomolecular Analysis Facility - Metabolomics Node (NBAF-B), School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Viant
mesh_terms: D000818:Animals; D057231:Climate Change; D033342:Copepoda / Q000378:metabolism*; D016002:Discriminant Analysis; D004281:Docosahexaenoic Acids / Q000378:metabolism; D017753:Ecosystem; D015118:Eicosapentaenoic Acid / Q000378:metabolism; D057232:Global Warming; D006863:Hydrogen-Ion Concentration; D016018:Least-Squares Analysis; D013058:Mass Spectrometry; D055442:Metabolome; D025341:Principal Component Analysis; D012623:Seawater / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature
chemical_list: D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid