Development of abiotic stress tolerance via bZIP-type transcription factor LIP19 in common wheat

J Exp Bot. 2008;59(4):891-905. doi: 10.1093/jxb/ern014. Epub 2008 Mar 7.

Abstract

Cereal lip19 genes encoding bZIP-type transcription factors are assumed to play a regulatory role in gene expression during the cold acclimation process. However, no direct evidence shows an association of LIP19-type bZIPs with stress tolerance or activation of stress-responsive Cor/Lea genes. To understand the molecular basis of development of abiotic stress tolerance through the LIP19 transcription factor, a wheat lip19 homologue, Wlip19, was isolated and characterized. Wlip19 expression was activated by low temperature in seedlings and was higher in a freezing-tolerant cultivar than in a freezing-sensitive one. Wlip19 also responded to drought and exogenous ABA treatment. Wlip19-expressing transgenic tobacco showed a significant increase in abiotic stress tolerance, especially freezing tolerance. Expression of a GUS reporter gene under the control of promoter sequences of four wheat Cor/Lea genes, Wdhn13, Wrab17, Wrab18, and Wrab19, was enhanced by Wlip19 expression in wheat callus and tobacco plants. These results indicate that WLIP19 acts as a transcriptional regulator of Cor/Lea genes in the development of abiotic stress tolerance. Moreover, direct protein-protein interaction between WLIP19 and a wheat OBF1 homologue TaOBF1, another bZIP-type transcription factor, was observed, suggesting that this interaction is conserved in cereals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / pharmacology
  • Acclimatization
  • Basic-Leucine Zipper Transcription Factors / genetics
  • Basic-Leucine Zipper Transcription Factors / metabolism
  • Cold Temperature
  • Freezing
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant / physiology
  • Germination / drug effects
  • Nicotiana / metabolism
  • Osmolar Concentration
  • Phylogeny
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Triticum / genetics
  • Triticum / metabolism*

Substances

  • Basic-Leucine Zipper Transcription Factors
  • Plant Proteins
  • Transcription Factors
  • OBF1 protein, Zea mays
  • Abscisic Acid