title: HSP90 regulates temperature-dependent seedling growth in Arabidopsis by stabilizing the auxin co-receptor F-box protein TIR1.
abstract: Recent studies have revealed that a mild increase in environmental temperature stimulates the growth of Arabidopsis seedlings by promoting biosynthesis of the plant hormone auxin. However, little is known about the role of other factors in this process. In this report, we show that increased temperature promotes rapid accumulation of the TIR1 auxin co-receptor, an effect that is dependent on the molecular chaperone HSP90. In addition, we show that HSP90 and the co-chaperone SGT1 each interact with TIR1, confirming that TIR1 is an HSP90 client. Inhibition of HSP90 activity results in degradation of TIR1 and interestingly, defects in a range of auxin-mediated growth processes at lower as well as higher temperatures. Our results indicate that HSP90 and SGT1 integrate temperature and auxin signalling in order to regulate plant growth in a changing environment.
authors.affiliation: Section of Cell and Developmental Biology, University of San Diego California, Howard Hughes Medical Institute, 9500 Gilman Dr, La Jolla, California 92093, USA.
authors.forename: Renhou
authors.initials: R
authors.lastname: Wang
authors.affiliation: Section of Cell and Developmental Biology, University of San Diego California, Howard Hughes Medical Institute, 9500 Gilman Dr, La Jolla, California 92093, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: Kieffer
authors.affiliation: Section of Cell and Developmental Biology, University of San Diego California, Howard Hughes Medical Institute, 9500 Gilman Dr, La Jolla, California 92093, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Yu
authors.affiliation: Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kepinski
authors.affiliation: Section of Cell and Developmental Biology, University of San Diego California, Howard Hughes Medical Institute, 9500 Gilman Dr, La Jolla, California 92093, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Estelle
mesh_terms: D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D044783:F-Box Proteins / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism*; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism*; D009154:Mutation; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D036226:Seedlings / Q000254:growth & development*; D015398:Signal Transduction; D013696:Temperature
chemical_list: D029681:Arabidopsis Proteins; D044783:F-Box Proteins; D018841:HSP90 Heat-Shock Proteins; D007210:Indoleacetic Acids; D011956:Receptors, Cell Surface; C501405:TIR1 protein, Arabidopsis; D005964:Glucosyltransferases; C515668:SGT1 protein, Arabidopsis