Open Access Repository

The ability to regulate voltage-gated K+-permeable channels in the mature root epidermis is essential for waterlogging tolerance in barley


Downloads per month over past year

Gill, MB, Zeng, F, Shabala, L ORCID: 0000-0002-5360-8496, Bohm, J ORCID: 0000-0002-8104-8705, Zhang, G, Zhou, M ORCID: 0000-0003-3009-7854 and Shabala, S ORCID: 0000-0003-2345-8981 2018 , 'The ability to regulate voltage-gated K+-permeable channels in the mature root epidermis is essential for waterlogging tolerance in barley' , Journal of Experimental Botany, vol. 69, no. 3 , pp. 667-680 , doi: 10.1093/jxb/erx429.

125785 - The ab...pdf | Download (706kB)

| Preview


Oxygen depletion under waterlogged conditions results in a compromised operation of H+-ATPase, with strong implications for membrane potential maintenance, cytosolic pH homeostasis, and transport of all nutrients across membranes. The above effects, however, are highly tissue specific and time dependent, and the causal link between hypoxia-induced changes to the cell’s ionome and plant adaptive responses to hypoxia is not well established. This work aimed to fill this gap and investigate the effects of oxygen deprivation on K+ signalling and homeostasis in plants, and potential roles of GORK (depolarization-activated outward-rectifying potassium) channels in adaptation to oxygen-deprived conditions in barley. A significant K+ loss was observed in roots exposed to hypoxic conditions; this loss correlated with the cell’s viability. Stress-induced K+ loss was stronger in the root apex immediately after stress onset, but became more pronounced in the root base as the stress progressed. The amount of K+ in shoots of plants grown in waterlogged soil correlated strongly with K+ flux under hypoxia measured in laboratory experiments. Hypoxia induced membrane depolarization; the severity of this depolarization was less pronounced in the tolerant group of cultivars. The expression of GORK was down-regulated by 1.5-fold in mature root but it was up-regulated by 10-fold in the apex after 48 h hypoxia stress. Taken together, our results suggest that the GORK channel plays a central role in K+ retention and signalling under hypoxia stress, and measuring hypoxia-induced K+ fluxes from the mature root zone may be used as a physiological marker to select waterlogging-tolerant varieties in breeding programmes.

Item Type: Article
Authors/Creators:Gill, MB and Zeng, F and Shabala, L and Bohm, J and Zhang, G and Zhou, M and Shabala, S
Keywords: GORK, H+-ATPase, H+-PPase, hypoxia, ionic homeostasis, potassium, signalling, viability staining, waterlogging.
Journal or Publication Title: Journal of Experimental Botany
Publisher: Oxford Univ Press
ISSN: 0022-0957
DOI / ID Number: 10.1093/jxb/erx429
Copyright Information:

© The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0)

Related URLs:
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page