CaZF, a plant transcription factor functions through and parallel to HOG and calcineurin pathways in Saccharomyces cerevisiae to provide osmotolerance

PLoS One. 2009;4(4):e5154. doi: 10.1371/journal.pone.0005154. Epub 2009 Apr 13.

Abstract

Salt-sensitive yeast mutants were deployed to characterize a gene encoding a C2H2 zinc finger protein (CaZF) that is differentially expressed in a drought-tolerant variety of chickpea (Cicer arietinum) and provides salinity-tolerance in transgenic tobacco. In Saccharomyces cerevisiae most of the cellular responses to hyper-osmotic stress is regulated by two interconnected pathways involving high osmolarity glycerol mitogen-activated protein kinase (Hog1p) and Calcineurin (CAN), a Ca(2+)/calmodulin-regulated protein phosphatase 2B. In this study, we report that heterologous expression of CaZF provides osmotolerance in S. cerevisiae through Hog1p and Calcineurin dependent as well as independent pathways. CaZF partially suppresses salt-hypersensitive phenotypes of hog1, can and hog1can mutants and in conjunction, stimulates HOG and CAN pathway genes with subsequent accumulation of glycerol in absence of Hog1p and CAN. CaZF directly binds to stress response element (STRE) to activate STRE-containing promoter in yeast. Transactivation and salt tolerance assays of CaZF deletion mutants showed that other than the transactivation domain a C-terminal domain composed of acidic and basic amino acids is also required for its function. Altogether, results from this study suggests that CaZF is a potential plant salt-tolerance determinant and also provide evidence that in budding yeast expression of HOG and CAN pathway genes can be stimulated in absence of their regulatory enzymes to provide osmotolerance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Calcineurin / genetics
  • Calcineurin / metabolism*
  • Cicer / genetics
  • Cicer / physiology
  • Droughts
  • Glycerol / metabolism
  • Mitogen-Activated Protein Kinases / genetics
  • Mitogen-Activated Protein Kinases / metabolism*
  • Molecular Sequence Data
  • Nicotiana / genetics
  • Nicotiana / physiology
  • Phylogeny
  • Plant Proteins / classification
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plants, Genetically Modified
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae / physiology*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Salt Tolerance / genetics*
  • Salt-Tolerant Plants / genetics
  • Salt-Tolerant Plants / physiology
  • Signal Transduction / physiology*
  • Transcription Factors / classification
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Zinc Fingers

Substances

  • Plant Proteins
  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • HOG1 protein, S cerevisiae
  • Mitogen-Activated Protein Kinases
  • Calcineurin
  • Glycerol