Deregulation of sucrose-controlled translation of a bZIP-type transcription factor results in sucrose accumulation in leaves

PLoS One. 2012;7(3):e33111. doi: 10.1371/journal.pone.0033111. Epub 2012 Mar 22.

Abstract

Sucrose is known to repress the translation of Arabidopsis thaliana AtbZIP11 transcript which encodes a protein belonging to the group of S (S--stands for small) basic region-leucine zipper (bZIP)-type transcription factor. This repression is called sucrose-induced repression of translation (SIRT). It is mediated through the sucrose-controlled upstream open reading frame (SC-uORF) found in the AtbZIP11 transcript. The SIRT is reported for 4 other genes belonging to the group of S bZIP in Arabidopsis. Tobacco tbz17 is phylogenetically closely related to AtbZIP11 and carries a putative SC-uORF in its 5'-leader region. Here we demonstrate that tbz17 exhibits SIRT mediated by its SC-uORF in a manner similar to genes belonging to the S bZIP group of the Arabidopsis genus. Furthermore, constitutive transgenic expression of tbz17 lacking its 5'-leader region containing the SC-uORF leads to production of tobacco plants with thicker leaves composed of enlarged cells with 3-4 times higher sucrose content compared to wild type plants. Our finding provides a novel strategy to generate plants with high sucrose content.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Base Sequence
  • Basic-Leucine Zipper Transcription Factors / chemistry
  • Basic-Leucine Zipper Transcription Factors / classification
  • Basic-Leucine Zipper Transcription Factors / genetics*
  • DNA Primers
  • Molecular Sequence Data
  • Open Reading Frames
  • Phylogeny
  • Plant Leaves / metabolism*
  • Plants, Genetically Modified
  • Protein Biosynthesis*
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Sucrose / metabolism*

Substances

  • Basic-Leucine Zipper Transcription Factors
  • DNA Primers
  • RNA, Messenger
  • Sucrose