Related Experiment Video
Updated: May 7, 2026

Tuning Degradation to Achieve Specific and Efficient Protein Depletion
Published on: July 20, 2019
Auxin-binding protein 1 is a negative regulator of the SCF(TIR1/AFB) pathway
Alexandre Tromas1, Sébastien Paque, Vérène Stierlé
11] Institut des Sciences du Végétal (ISV), UPR2355 Centre National de la Recherche Scientifique, Saclay Plant Sciences, 1 Avenue de la Terrasse, batiment 23, 91198 Gif sur Yvette, France [2].
Abstract:
Auxin is a major plant hormone that controls most aspects of plant growth and development. Auxin is perceived by two distinct classes of receptors: transport inhibitor response 1 (TIR1, or auxin-related F-box (AFB)) and auxin/indole-3-acetic acid (AUX/IAA) coreceptors, that control transcriptional responses to auxin, and the auxin-binding protein 1 (ABP1), that controls a wide variety of growth and developmental processes. To date, the mode of action of ABP1 is still poorly understood and its functional interaction with TIR1/AFB-AUX/IAA coreceptors remains elusive. Here we combine genetic and biochemical approaches to gain insight into the integration of these two pathways. We find that ABP1 is genetically upstream of TIR1/AFBs; ABP1 knockdown leads to an enhanced degradation of AUX/IAA repressors, independently of its effects on endocytosis, through the SCF(TIR1/AFB) E3 ubiquitin ligase pathway. Combining positive and negative regulation of SCF ubiquitin-dependent pathways might be a common mechanism conferring tight control of hormone-mediated responses.
Related Concept Videos
Cell Signaling in Plants
Allosteric Proteins-ATCase
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...
Negative Regulator Molecules
The Intrinsic Apoptotic Pathway
Canonical Wnt Signaling Pathway
Anaphase Promoting Complex

