A WRKY transcription factor participates in dehydration tolerance in Boea hygrometrica by binding to the W-box elements of the galactinol synthase (BhGolS1) promoter

Planta. 2009 Nov;230(6):1155-66. doi: 10.1007/s00425-009-1014-3. Epub 2009 Sep 17.

Abstract

Accumulation of compatible osmolytes, such as soluble sugars, in plants is an important osmoprotective mechanism. Sugars play a role in osmotic adjustment and are associated with stabilization of proteins and cell structures, reactive oxygen species scavenging, signaling functions or induction of adaptive pathways. Galactinol is the galactosyl donor for the synthesis of raffinose family oligosaccharides (RFOs) and its synthesis by galactinol synthase (GolS) is the first committed step of the RFOs biosynthetic pathway. GolS genes are induced by a variety of stresses in both stress-sensitive and tolerant-plant species; however, the mechanism of transcriptional regulation is not fully established. In this paper, we characterized a GolS gene (BhGolS1) that was dehydration and ABA-inducible in the resurrection plant Boea hygrometrica and conferred dehydration tolerance in a transgenic tobacco system. Four W-box cis-elements were identified in the BhGolS1 promoter and shown to be bound by an early dehydration and ABA-inducible WRKY gene (BhWRKY1). These data suggest a mechanism where BhWRKY1 is likely to function in an ABA-dependent signal pathway to regulate BhGolS1 expression, which leads to the accumulation of RFOs in desiccation-tolerant B. hygrometrica leaves.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / pharmacology
  • Acclimatization / drug effects
  • Base Sequence
  • Binding Sites / genetics
  • Blotting, Western
  • Chromatin Immunoprecipitation
  • Galactosyltransferases / genetics*
  • Galactosyltransferases / metabolism
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Plant / drug effects
  • Magnoliopsida / genetics*
  • Magnoliopsida / growth & development
  • Magnoliopsida / metabolism
  • Molecular Sequence Data
  • Plant Growth Regulators / pharmacology
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plants, Genetically Modified
  • Promoter Regions, Genetic / genetics*
  • Protein Binding
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tobacco / genetics
  • Tobacco / growth & development
  • Tobacco / metabolism
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Water / metabolism
  • Water / pharmacology

Substances

  • Plant Growth Regulators
  • Plant Proteins
  • Transcription Factors
  • Water
  • Abscisic Acid
  • Galactosyltransferases
  • inositol 1-alpha-galactosyltransferase

Associated data

  • GENBANK/FJ222452
  • GENBANK/FJ222453