RT Journal Article
SR Electronic
T1 Larval zebrafish use olfactory detection of sodium and chloride to avoid salt-water
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.08.19.258061
DO 10.1101/2020.08.19.258061
A1 Kristian J. Herrera
A1 Thomas Panier
A1 Drago Guggiana-Nilo
A1 Florian Engert
YR 2020
UL http://biorxiv.org/content/early/2020/08/20/2020.08.19.258061.abstract
AB Salinity levels constrain the habitable environment of all aquatic organisms. Zebrafish are freshwater fish that cannot tolerate high salt environments and would, therefore, benefit from neural mechanisms that enable the navigation of salt gradients to avoid high salinity. Yet, zebrafish lack epithelial sodium channels, the primary conduit land animals use to taste sodium. This suggests fish may possess novel, undescribed mechanisms for salt detection. In the present study, we show that zebrafish, indeed, respond to small temporal increases in salt by reorienting more frequently. Further, we use calcium imaging techniques to identify the olfactory system as the primary sense used for salt detection, and we find that a specific subset of olfactory receptor neurons encodes absolute salinity concentrations by detecting monovalent anions and cations. In summary, our study establishes that zebrafish larvae have the ability to navigate, and thus detect salinity gradients, and that this is achieved through previously undescribed sensory mechanisms for salt detection.Competing Interest StatementThe authors have declared no competing interest.