AtUBC32, AtUBC33, and AtUBC34 comprise Arabidopsis group XIV E2 ubiquitin-conjugating enzymes. Yeast two-hybrid, in vitro pull-down, and bimolecular fluorescence complementation assays revealed that group XIV E2s are interacting partners of the U-box-type E3 ligase PUB19, a negative regulator of drought stress response. These three AtUBCs are co-localized with PUB19 to the punctae-like structures, most of which reside on the endoplasmic reticulum membrane of tobacco leaf cells. Suppression of AtUBC32, AtUBC33, and AtUBC34 resulted in increased abscisic acid-mediated stomatal closure and tolerance to drought stress. These results indicate that Arabidopsis group XIV E2s play negative roles in drought stress response.
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science
- Plant Science