Ethylene as a Stomatal Signalling Hub: Integrating Hormonal and Stress Signals to Optimize Stomatal Responses.

Ethylene regulates stomatal responses through a bidirectional mechanism involving both closure-promoting and antagonistic pathways.

• Why it matters: Understanding how ethylene influences stomatal behavior is crucial because it plays a key role in plant stress responses and growth regulation, yet its effects are paradoxical and not fully integrated.
• What they did: The authors synthesized current evidence into a model where ethylene produces two opposing outputs: one promoting closure via Gα-dependent, RBOHD/F-mediated H2O2, NO, and H2S signals, and another opposing closure through EIN2-dependent flavonol accumulation that scavenges guard-cell ROS.
• The result: This mechanistic framework clarifies ethylene's complex role in stomatal regulation, offering insights to optimize plant growth and stress resilience by manipulating ethylene signaling pathways.