Complex regulation by Apetala2 domain-containing transcription factors revealed through analysis of the stress-responsive TdCor410b promoter from durum wheat

PLoS One. 2013;8(3):e58713. doi: 10.1371/journal.pone.0058713. Epub 2013 Mar 19.

Abstract

Expression of the wheat dehydrin gene Cor410b is induced several fold above its non-stressed levels upon exposure to stresses such as cold, drought and wounding. Deletion analysis of the TdCor410b promoter revealed a single functional C-repeat (CRT) element. Seven transcription factors (TFs) were shown to bind to this CRT element using yeast one-hybrid screens of wheat and barley cDNA libraries, of which only one belonged to the DREB class of TFs. The remaining six encoded ethylene response factors (ERFs) belong to three separate subfamilies. Analysis of binding selectivity of these TFs indicated that all seven could bind to the CRT element (GCCGAC), and that three of the six ERFs could bind both to the CRT element and the ethylene-responsive GCC-box (GCCGCC). The TaERF4 subfamily members specifically bound the CRT element, and did not bind either the GCC-box or DRE element (ACCGAC). Molecular modeling and site-directed mutagenesis identified a single residue Pro42 in the Apetala2 (AP2) domain of TaERF4-like proteins that is conserved in monocotyledonous plants and is responsible for the recognition selectivity of this subfamily. We suggest that both DREB and ERF proteins regulate expression of the Cor410b gene through a single, critical CRT element. Members of the TaERF4 subfamily are specific, positive regulators of Cor410b gene expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA, Plant / genetics
  • Gene Expression Regulation, Plant
  • Genes, Plant
  • Models, Molecular
  • Molecular Sequence Data
  • Phylogeny
  • Plant Proteins / chemistry
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plants, Genetically Modified
  • Promoter Regions, Genetic
  • Sequence Homology, Amino Acid
  • Stress, Physiological
  • Transcription Factors / chemistry
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Triticum / genetics*
  • Triticum / metabolism

Substances

  • DNA, Plant
  • Plant Proteins
  • Transcription Factors

Associated data

  • GENBANK/JN681186
  • GENBANK/JN681187
  • GENBANK/JN681188
  • GENBANK/JN681189
  • GENBANK/JN681190
  • GENBANK/JN681191
  • GENBANK/JN681192
  • GENBANK/JN681193

Grants and funding

This work was supported by the Masters of Plant Biotechnology Project (Plant SC 7229A WT & SC7229B WT) at the University of Adelaide, by the Australian Research Council, the Grains Research and Development Corporation, the Government of South Australia and the DuPont Ag Biotechnology Company. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript, except SS and ST (DuPont Ag Biotechnology Company), who were involved in the manuscript preparation.