title: Redundant ERF-VII Transcription Factors Bind to an Evolutionarily Conserved cis-Motif to Regulate Hypoxia-Responsive Gene Expression in Arabidopsis.
abstract: The response of Arabidopsis thaliana to low-oxygen stress (hypoxia), such as during shoot submergence or root waterlogging, includes increasing the levels of ∼50 hypoxia-responsive gene transcripts, many of which encode enzymes associated with anaerobic metabolism. Upregulation of over half of these mRNAs involves stabilization of five group VII ethylene response factor (ERF-VII) transcription factors, which are routinely degraded via the N-end rule pathway of proteolysis in an oxygen- and nitric oxide-dependent manner. Despite their importance, neither the quantitative contribution of individual ERF-VIIs nor the cis-regulatory elements they govern are well understood. Here, using single- and double-null mutants, the constitutively synthesized ERF-VIIs RELATED TO APETALA2.2 (RAP2.2) and RAP2.12 are shown to act redundantly as principle activators of hypoxia-responsive genes; constitutively expressed RAP2.3 contributes to this redundancy, whereas the hypoxia-induced HYPOXIA RESPONSIVE ERF1 (HRE1) and HRE2 play minor roles. An evolutionarily conserved 12-bp cis-regulatory motif that binds to and is sufficient for activation by RAP2.2 and RAP2.12 is identified through a comparative phylogenetic motif search, promoter dissection, yeast one-hybrid assays, and chromatin immunopurification. This motif, designated the hypoxia-responsive promoter element, is enriched in promoters of hypoxia-responsive genes in multiple species.
authors.affiliation: Plant Physiology, University Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Gasch
authors.affiliation: Plant Physiology, University Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Fundinger
authors.affiliation: Plant Physiology, University Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Jana T
authors.initials: JT
authors.lastname: Müller
authors.affiliation: Center for Plant Cell Biology and Botany and Plant Sciences Department, University of California, Riverside, California 92521.
authors.forename: Travis
authors.initials: T
authors.lastname: Lee
authors.affiliation: Center for Plant Cell Biology and Botany and Plant Sciences Department, University of California, Riverside, California 92521.
authors.forename: Julia
authors.identifier: http://orcid.org/0000-0002-8568-7125
authors.initials: J
authors.lastname: Bailey-Serres
authors.affiliation: Plant Physiology, University Bayreuth, 95440 Bayreuth, Germany angelika.mustroph@uni-bayreuth.de.
authors.forename: Angelika
authors.initials: A
authors.lastname: Mustroph
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001483:Base Sequence; D015687:Cell Hypoxia / Q000235:genetics; D017124:Conserved Sequence; D004268:DNA-Binding Proteins; D019143:Evolution, Molecular; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D059372:Nucleotide Motifs / Q000235:genetics*; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; C569242:RAP2.12 protein, Arabidopsis; C525662:RAP2.2 protein, Arabidopsis; D014157:Transcription Factors