Ca sup 2+ transport in membrane vesicles from pinto bean leaves and its alteration after ozone exposure. [Phaseolus vulgaris]

Journal Article · Mon Oct 01 00:00:00 EDT 1990 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.94.2.788· OSTI ID:5950511

Castillo, F J; Heath, R L ^[1]

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1. Univ. of California, Riverside (USA)

The influence of ozone on Ca{sup 2+} 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 Ca{sup 2+} influx into the cell and (b) active Ca{sup 2+} efflux driven by an ATP-dependent system, which has two components: a primary Ca{sup 2+} transport directly linked to ATP which is partially activated by calmodulin and a H{sup +}/Ca{sup 2+} antiport coupled to activity of a H{sup +}-ATPase. The passive Ca{sup 2+} permeability is increased by ozone. A triangular pulse of ozone stimulates a higher influx of Ca{sup 2+} than does a square wave, even though the total dose with the same (0.6 microliter per liter {times} 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 Ca{sup 2+} extrusion mechanisms. On the other hand, leaves exposed to a triangular wave of ozone, exhibit visible injury and lost the ability of extruding Ca{sup 2+} out of the cell.

• OSTI ID: 5950511
• Journal Information: Plant Physiology; (USA), Vol. 94:2; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
CALCIUM COMPOUNDS
BIOCHEMICAL REACTION KINETICS
OZONE
TOXICITY
PHASEOLUS
PHYSIOLOGY
CATIONS
CELL MEMBRANES
INJURIES
LEAVES
PERMEABILITY
ALKALINE EARTH METAL COMPOUNDS
CELL CONSTITUENTS
CHARGED PARTICLES
IONS
KINETICS
LEGUMINOSAE
MAGNOLIOPHYTA
MAGNOLIOPSIDA
MEMBRANES
PLANTS
REACTION KINETICS
560300* - Chemicals Metabolism & Toxicology
551000 - Physiological Systems