Journal Article

Early Zn<sup>2+</sup>-induced effects on membrane potential account for primary heavy metal susceptibility in tolerant and sensitive <i>Arabidopsis</i> species

Lucia Kenderešová, Andrea Staňová, Ján Pavlovkin, Eva Ďurišová, Miriam Nadubinská, Milada Čiamporová and Miroslav Ovečka

in Annals of Botany

Published on behalf of The Annals of Botany Company

Volume 110, issue 2, pages 445-459
Published in print July 2012 | ISSN: 0305-7364
Published online May 2012 | e-ISSN: 1095-8290 | DOI: http://dx.doi.org/10.1093/aob/mcs111
Early Zn2+-induced effects on membrane potential account for primary heavy metal susceptibility in tolerant and sensitive Arabidopsis species

More Like This

Show all results sharing these subjects:

  • Ecology and Conservation
  • Evolutionary Biology
  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

Background and Aims

Uptake of heavy metals by plant root cells depends on electro-physiological parameters of the plasma membrane. In this study, responses of the plasma membrane in root cells were analysed where early reactions to the metal ion-induced stress are localized. Three different Arabidopsis species with diverse strategies of their adaptation to heavy metals were compared: sensitive Arabidopsis thaliana and tolerant A. halleri and A. arenosa.

Methods

Plants of A. thaliana Col-0 ecotype and plants of A. arenosa and A. halleri originating from natural metallicolous populations were exposed to high concentrations of Zn2+. Plants were tested for root growth rate, cellular tolerance, plant morphology and cell death in the root apex. In addition, the membrane potential (EM) of mature cortical root cells and changes in the pH of the liquid culture media were measured.

Key Results

Primary roots of A. halleri and A. arenosa plants grew significantly better at increased Zn2+ concentrations than A. thaliana plants. Elevated Zn2+ concentrations in the culture medium induced rapid changes in EM. The reaction was species-specific and concentration-dependent. Arabidopsis halleri revealed the highest insensitivity of the plasma membrane and the highest survival rate under prolonged treatment with extra-high concentrations. Plants were able to effectively adjust the pH in the control, but much less at Zn2+-induced lower pH.

Conclusions

The results indicate a similar mode of early reaction to Zn2+, but with different extent in tolerant and sensitive species of Arabidopsis. The sensitivity of A. thaliana and a high tolerance of A. halleri and A. arenosa were demonstrated. Plasma membrane depolarization was lowest in the hyperaccumulator A. halleri and highest in A. thaliana. This indicates that rapid membrane voltage changes are an excellent tool to monitor the effects of heavy metals.

Keywords: Arabidopsis arenosa; Arabidopsis halleri; Arabidopsis thaliana; heavy metal tolerance; membrane potential; pH; root growth; zinc; Zn2+

Journal Article.  9550 words.  Illustrated.

Subjects: Ecology and Conservation ; Evolutionary Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.