Glutaredoxin Function in Plant Stress Responses

Plants face a wide array of environmental challenges that disrupt cellular homeostasis, from drought and salinity to temperature extremes and pathogen attack. Central to adaptation is the maintenance of redox poise, in which glutaredoxins (GRXs) play a pivotal role. GRXs are small glutathione‐dependent oxidoreductases defined by distinct active‐site motifs (CPYC, CGFS, CC and related variants) that catalyse reversible thiol–disulfide exchange and deglutathionylation reactions. By modulating reactive oxygen species (ROS) levels and protein thiol status, GRXs safeguard enzyme function, regulate hormone signalling and influence gene expression. In leaves, they adjust stomatal aperture via guard‐cell hydrogen peroxide dynamics; in roots, they interact with transcriptional regulators to orchestrate nutrient‐responsive programmes. Across taxa—from Arabidopsis through cereals to cotton and tomato—GRXs integrate abiotic and biotic stress cues with developmental pathways, emerging as versatile hubs for enhancing stress tolerance in crops.

Research from Nature Portfolio

Foundational research demonstrated that RNA interference of a rice monothiol GRX isoform enhances drought tolerance by modulating hydrogen peroxide concentrations within guard cells. Suppression of this GRX reduces stomatal conductance, increases water‐use efficiency and heightens sensitivity to abscisic acid, leading to improved survival under water‐deficit conditions. This work defines a direct mechanistic connection between GRX‐mediated redox control and stomatal regulation during drought stress.

Glutaredoxin Function in Plant Stress Responses publication trend

The graph below shows the total number of articles in glutaredoxin function in plant stress responses across all publications each year (not limited to Nature Index journals).

Technical terms

Reactive oxygen species (ROS): Highly reactive molecules derived from oxygen, including hydrogen peroxide and superoxide, that can damage cellular components but also act as signalling messengers.

Glutaredoxin (GRX): A small enzyme that uses glutathione to catalyse reversible thiol–disulfide exchange reactions, thereby regulating protein redox state.

Monothiol/dithiol motif: Active‐site sequences in GRXs where monothiol (e.g. CGFS) contains a single cysteine residue and dithiol (e.g. CPYC) contains two, determining catalytic mechanism and substrate specificity.

Stomatal conductance: The rate of gas exchange through leaf stomata, influenced by guard‐cell turgor and redox signals, and central to transpiration and photosynthesis.

Transcription factor (TGA family): A protein that binds specific DNA elements to regulate stress‐responsive gene expression, modulated by physical interactions with GRXs.

References

1. Redox-inactive CC-type glutaredoxins interfere with TGA transcription factor–dependent repression of target promoters in roots. The Plant Cell (2025).
2. Glutaredoxin in Rice Growth, Development, and Stress Resistance: Mechanisms and Research Advances. International Journal of Molecular Sciences (2023).
3. Silencing of OsGRXS17 in rice improves drought stress tolerance by modulating ROS accumulation and stomatal closure. Scientific Reports (2017).