DOI

Both ion fluxes and changes of cytosolic pH take an active part in the signal transduction of different environmental stimuli. Here we studied the anoxia-induced alteration of cytosolic K+ concentration, [K+]cyt, and cytosolic pH, pHcyt, in rice and wheat, plants with different tolerances to hypoxia. The [K+]cyt and pHcyt were measured by fluorescence microscopy in single leaf mesophyll protoplasts loaded with the fluorescent potassium-binding dye PBFI-AM and the pH-sensitive probe BCECF-AM, respectively. Anoxic treatment caused an efflux of K+ from protoplasts of both plants after a lag-period of 300–450 s. The [K+]cyt decrease was blocked by tetraethylammonium (1 mM, 30 min pre-treatment) suggesting the involvement of plasma membrane voltage-gated K+ channels. The protoplasts of rice (a hypoxia-tolerant plant) reacted upon anoxia with a higher amplitude of the [K+]cyt drop. There was a simultaneous anoxia-dependent cytosolic acidification of protoplasts of both plants. The decrease of pHcyt was slower in wheat (a hypoxia-sensitive plant) while in rice protoplasts it was rapid and partially reversible. Ion fluxes between the roots of intact seedlings and nutrient solutions were monitored by ion-selective electrodes and revealed significant anoxia-induced acidification and potassium leakage that were inhibited by tetraethylammonium. The K+ efflux from rice was more distinct and reversible upon reoxygenation when compared with wheat seedlings.

Original languageEnglish
Article number1216
Pages (from-to)1-15
Number of pages14
JournalPlants
Volume9
Issue number9
DOIs
StatePublished - Sep 2020

    Research areas

  • Acidification, Anoxic signaling, Fluorescence microscopy, Oryza sativa, PH, Potassium, Triticum aestivum, OXYGEN DEFICIENCY, H+-ATPASE ACTIVITY, K+ RETENTION, potassium, ROOT TISSUES, CYTOPLASMIC PH, acidification, fluorescence microscopy, MOBILE ENERGY-SOURCE, anoxic signaling, BARLEY HORDEUM-VULGARE, CALCIUM, pH, PLANTS, ION CHANNELS

    Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Plant Science
  • Ecology

ID: 62488782