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Updated: Jul 22, 2026
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Measuring Spatial and Temporal Ca2+ Signals in Arabidopsis Plants
Published on: September 2, 2014
Oxidative Signals in Tobacco Increase Cytosolic Calcium
A. H. Price1, A. Taylor, S. J. Ripley
1School of Biological Sciences, University of Wales-Bangor, Bangor, Gwynedd LL57 2UW, United Kingdom.
The Plant Cell
|September 1, 1994
Summary
Hydrogen peroxide triggers a temporary rise in plant cell calcium, indicating a refractory period and distinct calcium signaling pathways. This calcium response plays a role in how plants manage oxidative stress.
Area of Science:
- Plant biology
- Molecular biology
- Biochemistry
Background:
- Aequorin, a calcium-sensitive luminescent protein, was reconstituted in genetically modified tobacco (Nicotiana plumbaginifolia) seedlings.
- Hydrogen peroxide (H2O2) treatment was used to investigate calcium signaling.
Purpose of the Study:
- To investigate the transient nature of cytosolic free calcium concentration ([Ca2+]cyt) changes induced by H2O2.
- To explore the potential for different signaling pathways and the role of redox state in plant oxidative stress responses.
Main Methods:
- Genetically transformed tobacco seedlings expressing apoaequorin were used.
- Seedlings were treated with h-coelenterazine to reconstitute aequorin.
- Treatments included hydrogen peroxide, cold shock, touching, buthionine sulfoximine, ascorbate peroxidase inhibitors, and lanthanum.
Main Results:
- H2O2 induced a transient, calcium-dependent luminescence, indicating a temporary increase in [Ca2+]cyt.
- A refractory period was observed, where prior H2O2 treatment reduced responsiveness to subsequent H2O2 application.
- H2O2 did not affect calcium mobilization by cold shock or touching, suggesting distinct calcium pools.
- Redox state modifiers affected H2O2-induced calcium transients.
- H2O2 treatment reduced superoxide dismutase activity, a reduction reversible by lanthanum.
Conclusions:
- Plant cells exhibit a refractory period in their calcium response to persistent hydrogen peroxide stimuli.
- Distinct signaling pathways involving different intracellular calcium pools are likely activated by various stress signals.
- Calcium plays a significant role in plant responses to oxidative stress, potentially by influencing enzyme activity like superoxide dismutase.
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