This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Castillo, F. J. Articles by Heath, R. L. Search for Related Content PubMed PubMed Citation Articles by Castillo, F. J. Articles by Heath, R. L. Agricola Articles by Castillo, F. J. Articles by Heath, R. L.

Environmental and Stress Physiology

Ca²⁺ Transport in Membrane Vesicles from Pinto Bean Leaves and Its Alteration after Ozone Exposure ¹

Department of Botany and Plant Sciences, University of California, Riverside, California 92521

The influence of ozone on Ca²⁺ transport in plant membranes from pinto bean (Phaseolus vulgaris L. var Pinto) leaves was investigated in vitro by means of a filtration method using purified vesicles. Two transport mechanisms located at the plasma membrane are involved in a response to ozone: (a) passive Ca²⁺ influx into the cell and (b) active Ca²⁺ efflux driven by an ATP-dependent system, which has two components: a primary Ca²⁺ transport directly linked to ATP which is partially activated by calmodulin and a H⁺/Ca²⁺ antiport coupled to activity of a H⁺-ATPase. The passive Ca²⁺ permeability is increased by ozone. A triangular pulse of ozone stimulates a higher influx of Ca²⁺ than does a square wave, even though the total dose was the same (0.6 microliter per liter x hour). Leaves exposed to a square wave did not exhibit visible injury and were still able to recover from oxidant stress by activation of calmodulin-dependent Ca²⁺ extrusion mechanisms. On the other hand, leaves exposed to a triangular wave of ozone, exhibit visible injury and lost the ability of extruding Ca²⁺ out of the cell.

¹ Financial support was provided by a fellowship from the Swiss FRNS to F.J.C.

This article has been cited by other articles:

				R. Endo and K. Omasa 3-D cell-level chlorophyll fluorescence imaging of ozone-injured sunflower leaves using a new passive light microscope system J. Exp. Bot., March 1, 2007; 58(4): 765 - 772. [Abstract] [Full Text] [PDF]

				K. Overmyer, M. Brosche, R. Pellinen, T. Kuittinen, H. Tuominen, R. Ahlfors, M. Keinanen, M. Saarma, D. Scheel, and J. Kangasjarvi Ozone-Induced Programmed Cell Death in the Arabidopsis radical-induced cell death1 Mutant Plant Physiology, March 1, 2005; 137(3): 1092 - 1104. [Abstract] [Full Text] [PDF]

				J. Leipner, K. Oxborough, and N. R. Baker Primary sites of ozone-induced perturbations of photosynthesis in leaves: identification and characterization in Phaseolus vulgaris using high resolution chlorophyll fluorescence imaging J. Exp. Bot., August 1, 2001; 52(361): 1689 - 1696. [Abstract] [Full Text] [PDF]

				G. Torsethaugen, E. J. Pell, and S. M. Assmann Ozone inhibits guard cell K+ channels implicated in stomatal opening PNAS, November 9, 1999; 96(23): 13577 - 13582. [Abstract] [Full Text] [PDF]