Overexpression of PtrABF gene, a bZIP transcription factor isolated from Poncirus trifoliata, enhances dehydration and drought tolerance in tobacco via scavenging ROS and modulating expression of stress-responsive genes

BMC Plant Biol. 2010 Oct 25;10:230. doi: 10.1186/1471-2229-10-230.

Abstract

Background: Drought is one of the major abiotic stresses affecting plant growth, development and crop productivity. ABA responsive element binding factor (ABF) plays an important role in stress responses via regulating the expression of stress-responsive genes.

Results: In this study, a gene coding for ABF (PtrABF) was isolated from Poncirus trifoliata (L.) Raf. PtrABF had a complete open reading frame of 1347 bp, encoding a 448 amino acid peptide, and shared high sequence identities with ABFs from other plants. PtrABF was subcellularly targeted to the nucleus, exhibited transactivation activity in yeast cell and could bind to ABRE, supporting its role as a transcription factor. Expression levels of PtrABF were induced by treatments with dehydration, low temperature and ABA. Ectopic expression of PtrABF under the control of a CaMV 35S promoter in transgenic tobacco plants enhanced tolerance to both dehydration and drought. Under dehydration and drought conditions, the transgenic plants accumulated lower levels of reactive oxygen species compared with wild type, accompanied by higher activities and expression levels of three antioxidant enzymes. In addition, steady-state mRNA levels of nine stress-responsive genes coding for either functional or regulatory proteins were induced to higher levels in the transgenic lines with or without drought stress.

Conclusions: PtrABF is a bZIP transcription factor and functions in positive modulation of drought stress tolerance. It may be an important candidate gene for molecular breeding of drought-tolerant plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / pharmacology
  • Adaptation, Physiological / drug effects
  • Amino Acid Sequence
  • Basic-Leucine Zipper Transcription Factors / classification
  • Basic-Leucine Zipper Transcription Factors / genetics
  • Catalase / metabolism
  • Cell Nucleus / metabolism
  • Gene Expression Regulation, Plant / drug effects
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Molecular Sequence Data
  • Peroxidase / metabolism
  • Phylogeny
  • Plant Growth Regulators / pharmacology
  • Plant Proteins / classification
  • Plant Proteins / genetics*
  • Plants, Genetically Modified
  • Poncirus / genetics*
  • Reactive Oxygen Species / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Stress, Physiological / drug effects
  • Superoxide Dismutase / metabolism
  • Temperature
  • Tobacco / genetics*
  • Tobacco / metabolism
  • Water / metabolism
  • Water / pharmacology

Substances

  • Basic-Leucine Zipper Transcription Factors
  • Plant Growth Regulators
  • Plant Proteins
  • Reactive Oxygen Species
  • Water
  • Green Fluorescent Proteins
  • Abscisic Acid
  • Catalase
  • Peroxidase
  • Superoxide Dismutase

Associated data

  • GENBANK/HM171703