Redox-regulated Aux/IAA multimerization modulates auxin responses

• 成果类型: Article
• 署名作者: Roy, Dipan; Mehra, Poonam; Clark, Lisa; Mukkawar, Vaishnavi; Bellande, Kevin; Martin-Arevalillo, Raquel; Ghosh, Srayan; Ingole, Kishor D.; Bhagat, Prakash Kumar; Brown, Adrian; Sue-ob, Kawinnat; Jones, Andrew; Vermeer, Joop E. M.; Vernoux, Teva; Lilley, Kathryn; Mullineaux, Phil; Bechtold, Ulrike; Bennett, Malcolm J.; Sadanandom, Ari
• 署名单位: Durham University; University of Nottingham; University of Neuchatel; Institut Agro; Universite de Montpellier; Centre National de la Recherche Scientifique (CNRS); INRAE; Centre National de la Recherche Scientifique (CNRS); Ecole Normale Superieure de Lyon (ENS de LYON); Universite Claude Bernard Lyon 1; INRAE; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Physics (INP); Universite Federale Toulouse Midi-Pyrenees (ComUE); Universite de Toulouse; Institut National Polytechnique de Toulouse; University of Cambridge; University of Liverpool; University of Essex
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-12581
• DOI: 10.1126/science.adu1470
• 发表日期: 2025-07-17
• 关键词: multiple sequence alignment; lateral root-formation; box protein tir1; transcriptional repression; pb1 domain; degradation; mechanisms; expression; vectors

摘要

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.