ABSTRACT
Lipids are fundamental components of many biological structures, and their composition is partially diet dependent. Differences in lipid composition can impact the functioning of cellular membranes and proteins, subsequently altering the organism's ability to respond to environmental conditions. The American lobster (Homarus americanus) is an economically important shellfish in New England and is frequently kept in lobster impoundments (pounds) for prolonged periods, typically on a diet of herring, which differs from the natural diet of wild-caught lobsters. In this study, we compared the lipid composition of lobster muscle, heart and hepatopancreas from wild-caught and from pound-kept lobsters that were fed either herring or blue mussels. We performed lipidomic analysis, measured mitochondrial function, determined gene expression of cellular stress markers and evaluated thermal stress tolerance by assessing heart and ventilation rate, as well as hemolymph oxygenation during a fast progressive temperature challenge. We found a significant shift in lipid composition in pound-kept lobster hearts together with reduced mitochondrial function, and increased gene transcription of the cellular stress markers HSP70 and AMPK, indicating a worse nutritional state, compared with wild-fed lobsters. The changes did not lead to a shift in thermal thresholds, indicating a substantial plasticity and tolerance to compensate for adverse diet-induced conditions. This study mechanistically links diet, lipid composition, mitochondrial function and thermal tolerance and highlights the need for a more detailed understanding of cellular processes to understand climate change-induced impacts on marine invertebrates.
Footnotes
Author contributions
Conceptualization: M.C.B., C.P.H.V., A.R.G., M.F.; Data curation: M.F.; Formal analysis: M.C.B., Y.S.-O., C.P.H.V., A.R.G., I.M.P.; Funding acquisition: M.F.; Investigation: M.C.B., Y.S.-O., C.P.H.V., A.R.G.; Methodology: M.C.B., Y.S.-O., C.P.H.V., A.R.G., M.F.; Supervision: A.R.G., M.F.; Visualization: I.M.P.; Writing – original draft: M.C.B.; Writing – review & editing: M.C.B., C.P.H.V., A.R.G., I.M.P., M.F.
Funding
This work was supported by the University of New England Marine Science graduate program to M.C.B.; the National Science Foundation [1460861 to M.F.]; the National Institutes of Health [P30GM106391 to the Proteomics and Lipidomics and Physiology Cores at the MaineHealth Institute for Research, Center for Molecular Medicine]; and the National Institute of General Medical Sciences [P20GM121301 to the Physiology Core at Center for Clinical and Translational Research]. A.R.G. was supported by the National Institutes of Health/National Institute of Children's Health and Disease [R01HD112474] and funds from MaineHealth Institute for Research. Deposited in PMC for release after 12 months.
Data and resource availability
Data are available from Dryad (Butler et al., 2025): https://doi.org/10.5061/dryad.9w0vt4brt
