Biochemical and Structural Insights into the Mechanism of DNA Recognition by Arabidopsis ETHYLENE INSENSITIVE3

PLoS One. 2015 Sep 9;10(9):e0137439. doi: 10.1371/journal.pone.0137439. eCollection 2015.

Abstract

Gaseous hormone ethylene regulates numerous stress responses and developmental adaptations in plants by controlling gene expression via transcription factors ETHYLENE INSENSITIVE3 (EIN3) and EIN3-Like1 (EIL1). However, our knowledge regarding to the accurate definition of DNA-binding domains (DBDs) within EIN3 and also the mechanism of specific DNA recognition by EIN3 is limited. Here, we identify EIN3 82-352 and 174-306 as the optimal and core DBDs, respectively. Results from systematic biochemical analyses reveal that both the number of EIN3-binding sites (EBSs) and the spacing length between two EBSs affect the binding affinity of EIN3; accordingly, a new DNA probe which has higher affinity with EIN3 than ERF1 is also designed. Furthermore, we show that palindromic repeat sequences in ERF1 promoter are not necessary for EIN3 binding. Finally, we provide, to our knowledge, the first crystal structure of EIN3 core DBD, which contains amino acid residues essential for DNA binding and signaling. Collectively, these data suggest the detailed mechanism of DNA recognition by EIN3 and provide an in-depth view at molecular level for the transcriptional regulation mediated by EIN3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / chemistry
  • Arabidopsis / genetics*
  • Arabidopsis Proteins / chemistry*
  • Arabidopsis Proteins / genetics
  • Binding Sites
  • Crystallography, X-Ray*
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / genetics
  • Electrophoretic Mobility Shift Assay
  • Ethylenes / metabolism
  • Gene Expression Regulation, Plant
  • Inverted Repeat Sequences
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / genetics
  • Peptide Termination Factors / chemistry
  • Peptide Termination Factors / genetics
  • Plants, Genetically Modified
  • Promoter Regions, Genetic
  • Protein Conformation
  • Protein Structure, Tertiary
  • Signal Transduction
  • Transcription Factors / chemistry*
  • Transcription Factors / genetics

Substances

  • Arabidopsis Proteins
  • DNA-Binding Proteins
  • EIL1 protein, Arabidopsis
  • EIN3 protein, Arabidopsis
  • Ethylenes
  • Nuclear Proteins
  • Peptide Termination Factors
  • Transcription Factors
  • eukaryotic release factor 1, Arabidopsis
  • ethylene

Grants and funding

This work was supported by the National Basic Research Foundation of China (http://www.most.gov.cn/; 2014CB964900 to C.Y.), and the National Natural Science Foundation of China (http://www.nsfc.gov.cn/; 31270838 to C.Y., 21472009 to C.Y.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.