University Of Tasmania
147647_Lipid kinases PIP5K7 and PIP5K9 are required for polyamine-triggered K+ efflux in Arabidopsis roots.pdf (1.46 MB)
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Lipid kinases PIP5K7 and PIP5K9 are required for polyamine-triggered K+ efflux in Arabidopsis roots

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journal contribution
posted on 2023-05-21, 04:00 authored by Zarza, X, Van Wijk, R, Svetlana ShabalaSvetlana Shabala, Hunkeler, A, Lefebvre, M, Rodriguez-Villalon, A, Sergey ShabalaSergey Shabala, Tiburcio, AF, Heilmann, I, Munnik, T
Polyamines, such as putrescine, spermidine and spermine (Spm), are low-molecular-weight polycationic molecules present in all living organisms. Despite their implication in plant cellular processes, little is known about their molecular mode of action. Here, we demonstrate that polyamines trigger a rapid increase in the regulatory membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2), and that this increase is required for polyamine effects on K+ efflux in Arabidopsis roots. Using in vivo 32Pi-labelling of Arabidopsis seedlings, low physiological (μm) concentrations of Spm were found to promote a rapid PIP2 increase in roots that was time- and dose-dependent. Confocal imaging of a genetically encoded PIP2 biosensor revealed that this increase was triggered at the plasma membrane. Differential 32Pi-labelling suggested that the increase in PIP2 was generated through activation of phosphatidylinositol 4-phosphate 5-kinase (PIP5K) activity rather than inhibition of a phospholipase C or PIP2 5-phosphatase activity. Systematic analysis of transfer DNA insertion mutants identified PIP5K7 and PIP5K9 as the main candidates involved in the Spm-induced PIP2 response. Using non-invasive microelectrode ion flux estimation, we discovered that the Spm-triggered K+ efflux response was strongly reduced in pip5k7 pip5k9 seedlings. Together, our results provide biochemical and genetic evidence for a physiological role of PIP2 in polyamine-mediated signalling controlling K+ flux in plants.


Publication title

The Plant Journal








Tasmanian Institute of Agriculture (TIA)


Wiley-Blackwell Publishing Ltd.

Place of publication

United Kingdom

Rights statement

© 2020 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd This is an open access article under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License, ( which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Repository Status

  • Open

Socio-economic Objectives

Other plant production and plant primary products not elsewhere classified