TY - JOUR ID - 1281 TI - Mechanism of auxin perception by the TIR1 ubiquitin ligase JO - Nature PY - 2007 SP - 640-645 AU - Tan, X. AU - Calderón Villalobos, L.I. AU - Sharon, M. AU - Zheng, C. AU - Robinson, C.V. AU - Estelle, M. AU - Zheng, N. VL - 446(7136) UR - DO - 10.1038/nature05731 AB - ArabidopsisAuxin is a pivotal plant hormone that controls many aspects of plant growth and development. Perceived by a small family of F-box proteins including transport inhibitor response 1 (TIR1), auxin regulates gene expression by promoting SCF ubiquitin-ligase-catalysed degradation of the Aux/IAA transcription repressors, but how the TIR1 F-box protein senses and becomes activated by auxin remains unclear. Here we present the crystal structures of the TIR1–ASK1 complex, free and in complexes with three different auxin compounds and an Aux/IAA substrate peptide. These structures show that the leucine-rich repeat domain of TIR1 contains an unexpected inositol hexakisphosphate co-factor and recognizes auxin and the Aux/IAA polypeptide substrate through a single surface pocket. Anchored to the base of the TIR1 pocket, auxin binds to a partially promiscuous site, which can also accommodate various auxin analogues. Docked on top of auxin, the Aux/IAA substrate peptide occupies the rest of the TIR1 pocket and completely encloses the hormone-binding site. By filling in a hydrophobic cavity at the protein interface, auxin enhances the TIR1–substrate interactions by acting as a ‘molecular glue’. Our results establish the first structural model of a plant hormone receptor. A2 - C1 - Molecular Signal Processing ER - TY - JOUR ID - 878 TI - Jasmonates: An update on biosynthesis, signal transduction and action in plant stress response, growth and development JO - Annals of Botany PY - 2007 SP - 681-697 AU - Wasternack, C. VL - 100 UR - DO - 10.1093/aob/mcm079 AB - A2 - C1 - Molecular Signal Processing ER - TY - JOUR ID - 831 TI - Isolation and characterization of the glutaminyl cyclases from Solanum tuberosum and Arabidopsis thaliana: implications for physiological functions JO - Biol. Chem PY - 2007 SP - 145-153 AU - Schilling, S. AU - Stenzel, I. AU - von Bohlen, A. AU - Wermann, M. AU - Schulz, K. AU - Demuth, H.-U. AU - Wasternack, C. VL - 388 UR - DO - 10.1515/BC.2007.016 AB - A2 - C1 - Molecular Signal Processing ER -