Extracellular ATP Signaling in Plant Stress Responses

Extracellular ATP (eATP) has emerged as a pivotal damage‐associated molecular pattern in plants, linking the perception of biotic and abiotic stress to adaptive responses. Upon cell damage or environmental challenge, ATP is released into the apoplast, where it is recognised by plasma‐membrane receptor kinases, notably P2K1 (DORN1). Activation of P2K1 precipitates downstream cascades including elevation of cytosolic Ca2+ signatures, production of reactive oxygen species (ROS), phosphorylation of NADPH oxidase RBOHD and modulation of gene expression. These events converge to regulate stomatal closure, cell‐wall reinforcement, ion homeostasis and defence gene networks, thereby enhancing tolerance to stresses such as salinity, drought and pathogen attack. Apyrases fine‐tune this signalling by hydrolysing eATP, controlling signal intensity and duration. Collectively, eATP signalling represents a versatile system through which plants integrate stress perception with physiological and transcriptional reprogramming to maintain homeostasis and productivity.

Research from Nature Portfolio

Recent studies have elucidated the mechanism by which eATP induces rapid stomatal closure via direct phosphorylation of the NADPH oxidase RBOHD by the eATP receptor kinase. Activation of this pathway elevates ROS levels in guard cells, triggering pore closure and enhancing resistance to bacterial pathogens. Mutational analysis of phosphorylation sites on RBOHD abolishes eATP‐induced stomatal responses, underscoring the specificity of receptor‐mediated signalling. These insights clarify how purinergic signalling modulates gas exchange, water use efficiency and pathogen defence in leaves.

Extracellular ATP Signaling in Plant Stress Responses publication trend

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

Technical terms

Extracellular ATP (eATP): adenosine triphosphate released into the apoplast acting as a signalling molecule.

P2K1 (DORN1): a plasma‐membrane lectin receptor kinase that recognises eATP and initiates downstream phosphorylation cascades.

Reactive oxygen species (ROS): chemically reactive molecules containing oxygen that serve as secondary messengers in stress signalling.

Cytosolic calcium signature: dynamic variations in intracellular Ca2+ concentration that encode stimulus‐specific information.

References

1. Extracellular ATP acts as a damage-associated molecular pattern (DAMP) signal in plants. Frontiers in Plant Science (2014).
2. Extracellular ATP elicits DORN1-mediated RBOHD phosphorylation to regulate stomatal aperture. Nature Communications (2017).
3. Extracellular ATP Signaling Is Mediated by H2O2 and Cytosolic Ca2+ in the Salt Response of Populus euphratica Cells. PLOS ONE (2012).
4. Apyrase Suppression Raises Extracellular ATP Levels and Induces Gene Expression and Cell Wall Changes Characteristic of Stress Responses. Plant Physiology (2014).
5. CPK28 is a modulator of purinergic signaling in plant growth and defense. The Plant Journal (2024).
6. Identifying Receptor Kinase Substrates Using an 8000 Peptide Kinase Client Library Enriched for Conserved Phosphorylation Sites. Molecular & Cellular Proteomics (2025).
7. DORN1/P2K1 and purino-calcium signalling in plants: making waves with extracellular ATP. Annals of Botany (2019).