The Role of Reactive Oxygen Species and Calcium Ions in Implementing the Stress-Protective Effect of γ-Aminobutyric Acid on Wheat Seedlings Under Heat Stress Conditions - Cytology and Genetics

γ-aminobutyric acid (GABA) is considered a molecule that combines the properties of a stress metabolite and a signaling molecule. At the same time, the importance of its functional interaction with other signaling mediators, in particular, reactive oxygen species (ROS) and calcium ions, for the implementation of stress-protective action on plant cells remains poorly researched. The authors studied the effect of GABA on the resistance of wheat seedlings (Triticum aestivum L., cultivar Doskonala) to potentially lethal heat stress and the participation of ROS and calcium in the manifestation of the effects of GABA. Treatment of seedlings with GABA in concentrations of 0.5 and 1 mM caused a significant increase in their survival after damaging heating in a water thermostat (10 min at 45°C). Under the influence of GABA, there was a transient increase in the content of hydrogen peroxide in the roots of seedlings, followed by an increase in the activity of antioxidant enzymes: superoxide dismutase, catalase, and guaiacol peroxidase. The specified effects of GABA were eliminated by the preliminary application of the hydrogen peroxide scavenger dimethylthiourea (DMTU) to the root incubation medium and were significantly suppressed in the presence of the NADPH oxidase inhibitor imidazole. At the same time, the treatment of seedlings with the chelator of extracellular calcium EGTA only partially eliminated the increase in the content of hydrogen peroxide and hardly affected the increase in the activity of antioxidant enzymes in the roots under the influence of GABA. Treatment with neomycin, an inhibitor of calcium uptake from intracellular compartments, caused a partial reduction in the effect of GABA on indicators of the state of the pro-/antioxidant system in wheat roots but did not eliminate these effects. Under the influence of GABA, damage to root cell membranes caused by heat stress was significantly reduced, which was manifested in a decrease in the release of UV-B-absorbing compounds from the cells and a decrease in the content of lipid peroxide oxidation products. At the same time, the stress-protective effect of GABA was eliminated by DMTU treatment and changed in the presence of calcium antagonists. A conclusion was made about the important role of ROS generated with the participation of NADPH oxidase in the implementation of the protective effect of GABA on wheat seedlings under conditions of heat stress and the partial dependence of its protective effects on calcium homeostasis.

Deep sea sensor reveals that corals produce reactive oxygen species

Just like us, corals breathe in oxygen and eat organic carbon. And just like us, as a byproduct of converting energy and oxygen in the body, corals produce reactive oxygen species (ROS), a family of chemical compounds that are naturally made by cells during cell division, while fighting off pathogens, and performing other physiological functions.

Non-specific LIPID TRANSFER PROTEIN 1 enhances immunity against tobacco mosaic virus in Nicotiana benthamiana

The non-specific lipid transfer protein LTP1 in Nicotiana benthamianafunctions in resistance to tobacco mosaic virus via mediating SA signaling pathways and ROS

Organic Chemistry - ROS generation - Beilstein-Institut

Organic Chemistry - ROS generation - Beilstein-Institut

Organic Chemistry - ROS generation - Beilstein-Institut

Transferred mitochondria accumulate reactive oxygen species, promoting proliferation

Transferred mitochondria do not always regulate cell behavior by simply restoring mitochondrial function, but rather, transferred mitochondria are dysfunctional, initiating downstream signaling and proliferation in response to reactive oxygen species.