The sucrose-regulated Arabidopsis transcription factor bZIP11 reprograms metabolism and regulates trehalose metabolism

New Phytol. 2011 Aug;191(3):733-45. doi: 10.1111/j.1469-8137.2011.03735.x. Epub 2011 Apr 27.

Abstract

• The Arabidopsis basic region-leucine zipper transcription factor 11 (bZIP11) is known to be repressed by sucrose through a translational inhibition mechanism that requires the conserved sucrose control peptide encoded by the mRNA leader. The function of bZIP11 has been investigated in over-expression studies, and bZIP11 has been found to inhibit plant growth. The addition of sugar does not rescue the growth inhibition phenotype. Here, the function of the bZIP11 transcription factor was investigated. • The mechanism by which bZIP11 regulates growth was studied using large-scale and dedicated metabolic analysis, biochemical assays and molecular studies. • bZIP11 induction results in a reprogramming of metabolism and activation of genes involved in the metabolism of trehalose and other minor carbohydrates such as myo-inositol and raffinose. bZIP11 induction leads to reduced contents of the prominent growth regulatory molecule trehalose 6-phosphate (T6P). • The metabolic changes detected mimic in part those observed in carbon-starved plants. It is proposed that bZIP11 is a powerful regulator of carbohydrate metabolism that functions in a growth regulatory network that includes T6P and the sucrose non-fermenting-1 related protein kinase 1 (SnRK1).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / growth & development
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Basic-Leucine Zipper Transcription Factors / genetics
  • Basic-Leucine Zipper Transcription Factors / metabolism*
  • Gene Expression Regulation, Plant / genetics*
  • Genes, Plant / genetics
  • Inositol / metabolism
  • Leucine Zippers / genetics
  • Plant Roots / growth & development
  • Promoter Regions, Genetic / genetics
  • Protein-Serine-Threonine Kinases / metabolism
  • Raffinose / biosynthesis
  • Seedlings / metabolism
  • Sucrose / metabolism*
  • Transgenes / genetics
  • Trehalose / metabolism*

Substances

  • ATB2 protein, Arabidopsis
  • Arabidopsis Proteins
  • Basic-Leucine Zipper Transcription Factors
  • Inositol
  • Sucrose
  • Trehalose
  • Protein-Serine-Threonine Kinases
  • SnRK1 protein, Arabidopsis
  • Raffinose