Bohm et al 2016_MolPlant_reprint.pdf (1.75 MB)
Venus flytrap HKT1-type channel provides for prey sodium uptake into carnivorous plant without conflicting with electrical excitability
journal contributionposted on 2023-05-18, 18:03 authored by Bohm, J, Scherzer, S, Sergey ShabalaSergey Shabala, Krol, E, Neher, E, Mueller, TD, Hedrich, R
The animal diet of the carnivorous Venus flytrap, Dionaea muscipula, contains a sodium load that enters the capture organ via an HKT1-type sodium channel, expressed in special epithelia cells on the inner trap lobe surface. DmHKT1 expression and sodium uptake activity is induced upon prey contact. Here, we analyzed the HKT1 properties required for prey sodium osmolyte management of carnivorous Dionaea. Analyses were based on homology modeling, generation of model-derived point mutants, and their functional testing in Xenopus oocytes. We showed that the wild-type HKT1 and its Na+- and K+-permeable mutants function as ion channels rather than K+ transporters driven by proton or sodium gradients. These structural and biophysical features of a high-capacity, Na+-selective ion channel enable Dionaea glands to manage prey-derived sodium loads without confounding the action potential-based information management of the flytrap.
Publication titleMolecular Plant
Department/SchoolTasmanian Institute of Agriculture (TIA)
Place of publicationUnited States
Rights statementCopyright 2016 The Author Licenced under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) https://creativecommons.org/licenses/by-nc-nd/4.0/