Related Experiment Video
Updated: Jun 14, 2025

Tuning Degradation to Achieve Specific and Efficient Protein Depletion
Published on: July 20, 2019
Redox-regulated Aux/IAA multimerization modulates auxin responses
Dipan Roy1, Poonam Mehra2, Lisa Clark1
1Department of Biosciences, Durham University, Durham, UK.
None:
Reactive oxygen species (ROS) function as key signals in plant adaptation to environmental stresses, such as drought. Roots respond to transient water unavailability by temporarily ceasing branching through the acclimative response xerobranching. In this study, we report how a xerobranching stimulus triggers rapid changes of ROS levels in root nuclei, triggering redox-dependent multimerization of the auxin repressor protein IAA3. Mutations in specific cysteine residues of IAA3 disrupt redox-mediated multimerization and interaction with co-repressor TPL, thereby attenuating IAA3-mediated target gene repression. Other AUX/IAA proteins also vary in their redox-mediated multimerization, which reveals a regulatory mechanism that connects dynamic changes in cellular redox status to auxin signaling. Our study reveals how ROS, auxin, and water availability intersect and shape root adaptive responses, thereby maintaining phenotypic plasticity in plants.
Related Concept Videos
Cell Signaling in Plants
The Antenna Complex
Photoreceptors and Plant Responses to Light
Plant Hormones
Regulation of the Unfolded Protein Response
Cooperative Allosteric Transitions

