5α-cyprinol sulfate, a bile salt from fish, induces diel vertical migration in Daphnia
Abstract
Prey are under selection to minimize predation losses. In aquatic environments many prey use chemical cues released by predators, which initiate predator-avoidance. A prominent example of behavioural predator-avoidance constitutes diel vertical migration (DVM) in the freshwater microcrustacean Daphnia spp., which is induced by chemical cues (kairomones) released by planktivorous fish. In a bioassay-guided approach using liquid chromatography and mass spectrometry we isolated the kairomone from fish incubation water and identified it as 5α-cyprinol sulfate inducing DVM in Daphnia at picomolar concentrations. The role of 5α-cyprinol sulfate in lipid digestion in fish explains why from an evolutionary perspective fish has not stopped releasing 5α-cyprinol sulfate despite the disadvantages for the releaser. The identification of the DVM-inducing kairomone enables investigating its spatial and temporal distribution and the underlying molecular mechanism of its perception. Furthermore, it allows to test if fish-mediated inducible defenses in other aquatic invertebrates are triggered by the same compound.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, Figure 1-figure supplement 2, Figure 4, Figure 3-figure supplement 2, and Figure 4-figure supplement 6.
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Data from: A bile salt from fish induces diel vertical migration in zooplanktonDryad Digital Repository, doi:10.5061/dryad.5d69g86.
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No external funding was received for this work.
Copyright
© 2019, Hahn et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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