title: Deregulation of sucrose-controlled translation of a bZIP-type transcription factor results in sucrose accumulation in leaves.
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.
authors.affiliation: Graduate School of Life Sciences, Tohoku University, Aoba, Sendai, Miyagi, Japan.
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Thalor
authors.forename: Thomas
authors.initials: T
authors.lastname: Berberich
authors.forename: Sung Shin
authors.initials: SS
authors.lastname: Lee
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Yang
authors.forename: Xujun
authors.initials: X
authors.lastname: Zhu
authors.forename: Ryozo
authors.initials: R
authors.lastname: Imai
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Tomonobu
authors.initials: T
authors.lastname: Kusano
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D050976:Basic-Leucine Zipper Transcription Factors / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D017931:DNA Primers; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D018515:Plant Leaves / Q000378:metabolism*; D030821:Plants, Genetically Modified; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013395:Sucrose / Q000378:metabolism*
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D017931:DNA Primers; D012333:RNA, Messenger; D013395:Sucrose