eCite Digital Repository

The mechanistic basis of sodium exclusion in Puccinellia tenuiflora under conditions of salinity and potassium deprivation


Han, Q-Q and Wang, Y-P and Li, J and Yin, X-C and Jiang, X-Y and Yu, M and Wang, S-M and Shabala, S and Zhang, J-L, The mechanistic basis of sodium exclusion in Puccinellia tenuiflora under conditions of salinity and potassium deprivation, The Plant journal : for cell and molecular biology, 112, (2) pp. 322-338. ISSN 1365-313X (2022) [Refereed Article]

Copyright Statement

Copyright 1999-2023 John Wiley & Sons, Inc. All rights reserved

DOI: doi:10.1111/tpj.15946


Soil salinity is a significant threat to global agriculture. Understanding salt exclusion mechanisms in halophyte species may be instrumental in improving salt tolerance in crops. Puccinellia tenuiflora is a typical salt-excluding halophytic grass often found in potassium-deprived saline soils. Our previous work showed that P. tenuiflora possesses stronger selectivity for K+ than for Na+ ; however, the mechanistic basis of this phenomenon remained elusive. Here, P. tenuiflora PutHKT1;5 was cloned and the functions of PutHKT1;5 and PutSOS1 were characterized using heterologous expression systems. Yeast assays showed that PutHKT1;5 possessed Na+ transporting capacity and was highly selective for Na+ over K+ . PutSOS1 was located at the plasma membrane and operated as a Na+ /K+ exchanger, with much stronger Na+ extrusion capacity than its homolog from Arabidopsis. PutHKT2;1 mediated high-affinity K+ and Na+ uptake and its expression levels were upregulated by mild salinity and K+ deprivation. Salinity-induced changes of root PutHKT1;5 and PutHKT1;4 transcript levels matched the expression pattern of root PutSOS1, which was consistent with root Na+ efflux. The transcript levels of root PutHKT2;1 and PutAKT1 were downregulated by salinity. Taken together, these findings demonstrate that the functional activity of PutHKT1;5 and PutSOS1 in P. tenuiflora roots is fine-tuned under saline conditions as well as by operation of other ion transporters/channel (PutHKT1;4, PutHKT2;1, and PutAKT1). This leads to the coordination of radial Na+ and K+ transport processes, their loading to the xylem, or Na+ retrieval and extrusion under conditions of mild salinity and/or K+ deprivation.

Item Details

Item Type:Refereed Article
Keywords:salinity; sodium; potassium; Puccinellia
Research Division:Biological Sciences
Research Group:Plant biology
Research Field:Plant physiology
Objective Division:Plant Production and Plant Primary Products
Objective Group:Other plant production and plant primary products
Objective Field:Other plant production and plant primary products not elsewhere classified
UTAS Author:Shabala, S (Professor Sergey Shabala)
ID Code:155138
Year Published:2022
Web of Science® Times Cited:2
Deposited By:Agriculture and Food Systems
Deposited On:2023-01-30
Last Modified:2023-03-23

Repository Staff Only: item control page