Display options
Share it on

Planta. 1990 Jan;180(2):139-46. doi: 10.1007/BF00193988.

Phosphate transport across biomembranes and cytosolic phosphate homeostasis in barley leaves.

Planta

T Mimura, K J Dietz, W Kaiser, M J Schramm, G Kaiser, U Heber

Affiliations

  1. Institut für Botanik und Pharmazeutische Biologie, Mittlerer Dallenbergweg 64, D-8700, Würzburg, Germany.

PMID: 24201937 DOI: 10.1007/BF00193988

Abstract

Barley (Hordeum vulgare L.) plants were grown hydroponically with or without inorganic phosphate (Pi) in the medium. Leaves were analyzed for the intercellular and the intracellular distribution of Pi. Most of the leaf Pi was contained in mesophyll cells; Pi concentrations were low in the xylem sap, the apoplast and in the cells of the epidermis. The vacuolar concentration of Pi in mesophyll cells depended on Pi availability in the nutrient medium. After infiltrating the intercellular space of leaves with solutions containing Pi, Pi was taken up by the mesophyll at rates higher than 2.5 μmol· (g fresh weight)(-1) · h(-1). Isolated mesophyll protoplasts did not possess a comparable capacity to take up Pi from the medium. Phosphate uptake by mesophyll protoplasts showed a biphasic dependence on Pi concentration. Uptake of Pi by Pi-deficient cells was faster than uptake by cells which had Pi stored in their vacuoles, although cytoplasmic Pi concentrations were comparable. Phosphate transport into isolated mesophyll vacuoles was dependent on their Pi content; it was stimulated by ATP. In contrast to the vacuolar Pi concentration, and despite different kinetic characteristics of the uptake systems for pi of the plasmalemma and the tonoplast, the cytoplasmic pi concentration was regulated in mesophyll cells within narrow limits under very different conditions of Pi availability in the nutrient medium, whereas vacuolar Pi concentrations varied within wide limits.

References

  1. Planta. 1980 Jul;149(2):138-43 - PubMed
  2. Planta. 1986 Mar;167(3):369-75 - PubMed
  3. Plant Physiol. 1988 Aug;87(4):822-7 - PubMed
  4. Planta. 1984 Jan;161(1):46-52 - PubMed
  5. Plant Physiol. 1983 Jan;71(1):108-11 - PubMed
  6. Arch Biochem Biophys. 1983 Aug;225(1):143-8 - PubMed
  7. Plant Physiol. 1988 Aug;87(4):828-32 - PubMed
  8. Plant Physiol. 1986 Apr;80(4):895-901 - PubMed
  9. Plant Physiol. 1985 Apr;77(4):1013-5 - PubMed
  10. Planta. 1984 May;160(6):490-9 - PubMed
  11. Anal Biochem. 1983 Jul 15;132(2):254-8 - PubMed
  12. Planta. 1986 Mar;167(3):376-81 - PubMed
  13. Plant Physiol. 1977 Jun;59(6):1146-55 - PubMed

Publication Types