This article, published in Nature in 2001, investigates the role of auxin in regulating the degradation of AUX/IAA proteins through the SCF^TIR1 ubiquitin ligase complex. The authors demonstrate that SCF^TIR1 interacts with AUX/IAA proteins, particularly AXR2/IAA7 and AXR3/IAA17, and that domain II of these proteins is essential for this interaction. Auxin treatment increases the binding of SCF^TIR1 to AUX/IAA proteins and promotes their degradation. The study also shows that dominant mutations in AUX/IAA genes or recessive mutations affecting SCF^TIR1 both lead to reduced auxin response, indicating that SCF^TIR1 is crucial for auxin signaling. The findings suggest that auxin promotes the degradation of AUX/IAA proteins, leading to diverse downstream effects in plant development. The authors propose a model where auxin derepresses the auxin-response pathway by targeting AUX/IAA proteins for degradation, which in turn activates ARF transcription factors and enhances auxin-regulated gene expression.This article, published in Nature in 2001, investigates the role of auxin in regulating the degradation of AUX/IAA proteins through the SCF^TIR1 ubiquitin ligase complex. The authors demonstrate that SCF^TIR1 interacts with AUX/IAA proteins, particularly AXR2/IAA7 and AXR3/IAA17, and that domain II of these proteins is essential for this interaction. Auxin treatment increases the binding of SCF^TIR1 to AUX/IAA proteins and promotes their degradation. The study also shows that dominant mutations in AUX/IAA genes or recessive mutations affecting SCF^TIR1 both lead to reduced auxin response, indicating that SCF^TIR1 is crucial for auxin signaling. The findings suggest that auxin promotes the degradation of AUX/IAA proteins, leading to diverse downstream effects in plant development. The authors propose a model where auxin derepresses the auxin-response pathway by targeting AUX/IAA proteins for degradation, which in turn activates ARF transcription factors and enhances auxin-regulated gene expression.