Molecular Biotechnology

, Volume 48, Issue 1, pp 76–86

Ectopic Expression of the K+ Channel β Subunits from Puccinellia tenuiflora (KPutB1) and Rice (KOB1) Alters K+ Homeostasis of Yeast and Arabidopsis

  • Sintho Wahyuning Ardie
  • Shunsaku Nishiuchi
  • Shenkui Liu
  • Tetsuo Takano
Research

DOI: 10.1007/s12033-010-9349-3

Cite this article as:
Ardie, S.W., Nishiuchi, S., Liu, S. et al. Mol Biotechnol (2011) 48: 76. doi:10.1007/s12033-010-9349-3

Abstract

In this study, we cloned a cDNA for the K+ channel β subunit from the halophyte Puccinellia tenuiflora and named it KPutB1. KPutB1 was preferentially expressed in the roots and was transiently induced by K+-starvation, salt stress, or the combination of both stresses. By yeast two-hybrid assay, we demonstrated that KPutB1 interacts with PutAKT1, α subunit of an AKT1-type K+ channel of P. tenuiflora. The functional relevance of this interaction on K+-nutrition was investigated by co-expression experiments in yeast under various ionic conditions, and K+ channel α and β subunit homologues from rice (OsAKT1 and KOB1, respectively) were included for comparison. Yeast co-expressing PutAKT1 and the β subunits (KPutB1 and KOB1) had better growth and higher K+-uptake ability than yeast expressing PutAKT1 alone. In contrast, yeast co-expressing the β subunits (KPutB1 and KOB1) with OsAKT1 had slower growth and lower K+ uptake than yeast expressing OsAKT1 alone. Arabidopsis plants over-expressing the K+ channel β subunit of P. tenuiflora or rice showed increased shoot K+ content and decreased root Na+ content under control, 75 mM NaCl, and K+-starvation stress conditions. These results suggest that ectopic expression of the K+ channel β subunit could alter K+ and Na+ homeostasis in plants.

Keywords

β subunit K+ channel K+ nutrition Puccinellia tenuiflora Salt stress 

Supplementary material

12033_2010_9349_MOESM1_ESM.doc (124 kb)
Supplementary material 1 (DOC 124 kb)

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Sintho Wahyuning Ardie
    • 1
    • 2
  • Shunsaku Nishiuchi
    • 1
  • Shenkui Liu
    • 3
  • Tetsuo Takano
    • 1
  1. 1.Asian Natural Environmental Science Center (ANESC)The University of TokyoTokyoJapan
  2. 2.Department of Agronomy and HorticultureBogor Agricultural UniversityBogorIndonesia
  3. 3.Alkali Soil Natural Environmental Science CenterNortheast Forestry UniversityHarbinChina

Personalised recommendations