Plant Cell Reports

, Volume 26, Issue 9, pp 1673–1679

High-affinity K+ transporter PhaHAK5 is expressed only in salt-sensitive reed plants and shows Na+ permeability under NaCl stress

  • Ryuichi Takahashi
  • Takayoshi Nishio
  • Nobumasa Ichizen
  • Tetsuo Takano
Biotic and Abiotic Stress

DOI: 10.1007/s00299-007-0364-1

Cite this article as:
Takahashi, R., Nishio, T., Ichizen, N. et al. Plant Cell Rep (2007) 26: 1673. doi:10.1007/s00299-007-0364-1

Abstract

To understand the mechanism of ion homeostasis in salt tolerant and sensitive plants, we isolated cDNAs for K+ transporter PhaHAK1-u and PhaHAK5-u from reed plants. PhaHAK1-u belongs to group I and PhaHAK5-u belongs to group IV by phylogenetic analysis, respectively. PhaHAK5-u is predicted to be a plasma membrane transporter, and shows high-affinity K+ transporter. Expression of PhaHAK5 was found in salt-sensitive reed plants, but not in any parts of salt-tolerant reed plants maintained under both control and K+ starvation conditions. Under the NaCl stress, the K+ uptake ability of the yeast strain expressing PhaHAK5-u was remarkably lower than that of the yeast strain expressing PhaHAK1-u, and PhaHAK5-u showed Na+ permeability. These results suggest that PhaHAK5 is one of the routes by which Na+ enters cells.

Keywords

PhaHAK5PhaHAK1Potassium transporterSalt stressReed plants

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Ryuichi Takahashi
    • 1
  • Takayoshi Nishio
    • 2
  • Nobumasa Ichizen
    • 2
  • Tetsuo Takano
    • 1
  1. 1.Asian Natural Environmental Science Center (ANESC)The University of TokyoTokyoJapan
  2. 2.Weed Science Center (WSC)Utsunomiya UniversityTochigiJapan