title: The Arabidopsis transcription factor bZIP11 activates auxin-mediated transcription by recruiting the histone acetylation machinery.
abstract: In higher plants, the hormone auxin orchestrates a diverse array of developmental and environmental responses mainly exerted via transcriptional control. In its absence, auxin-mediated transcription is postulated to be repressed by histone deacetylases, which convert chromatin into a highly packed inactive state. Here we present a converse mechanism where Arabidopsis bZIP11-related basic leucine zipper (bZIP) transcription factors interact via an amino-terminal activation domain with ADA2b adapter proteins to recruit the histone acetylation machinery to specific auxin-responsive genes. Gain, loss-of-function and pharmacological approaches as well as chromatin immunoprecipitation experiments addressing various components of the recruitment and acetylation machinery substantiate the proposed mechanism. Importantly, G-box-related cis-elements, frequently found in auxin-induced promoters, are shown to bind bZIP11-related bZIPs and to function as quantitative modulators of auxin-induced transcription. In conclusion, we describe a regulatory activation mechanism that serves as a rheostat to modulate auxin-mediated responses.
authors.affiliation: Julius-von-Sachs-Institut, Pharmazeutische Biologie, Julius-Maximilians-Universität Würzburg, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Weiste
authors.affiliation: Julius-von-Sachs-Institut, Pharmazeutische Biologie, Julius-Maximilians-Universität Würzburg, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dröge-Laser
mesh_terms: D000107:Acetylation / Q000187:drug effects; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D053263:Gene Regulatory Networks; D017343:Genes, Plant; D017930:Genes, Reporter; D051548:Histone Acetyltransferases / Q000378:metabolism; D006657:Histones / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000494:pharmacology*; D008954:Models, Biological; D008969:Molecular Sequence Data; D011485:Protein Binding / Q000187:drug effects; D011523:Protoplasts / Q000187:drug effects / Q000378:metabolism; D020218:Response Elements / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects*; D020798:Two-Hybrid System Techniques
chemical_list: C112599:ATB2 protein, Arabidopsis; D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D006657:Histones; D007210:Indoleacetic Acids; D051548:Histone Acetyltransferases