Pepper RING-Type E3 Ligase, CaAIAR1, Negatively Modulates ABA Signaling and Drought Stress Response by Controlling CaADBZ1 Stability.

Pepper CaAIAR1 E3 ligase reduces drought tolerance and ABA sensitivity by promoting CaADBZ1 degradation, with silencing enhancing drought resilience in pepper plants.

• Why it matters: Understanding how protein stability influences plant stress responses can reveal targets for improving drought tolerance, addressing the gap in knowledge about regulators of CaADBZ1 stability.
• What they did: The study used yeast two-hybrid assays, in vitro and in vivo interaction tests, and degradation assays to show CaAIAR1 ubiquitinates CaADBZ1, with expression induced by abiotic stresses and functional effects observed in transgenic plants.
• The result: Silencing CaAIAR1 increased drought tolerance and ABA sensitivity, while overexpression decreased these traits, indicating CaAIAR1's role upstream of CaADBZ1 in modulating drought stress and ABA signaling.