Altering Trehalose-6-Phosphate Content in Transgenic Potato Tubers Affects Tuber Growth and Alters Responsiveness to Hormones during Sprouting

Journal article


Publication Details

Author(s): Debast S, Nunes-Nesi A, Hajirezaei MR, Hofmann J, Sonnewald U, Fernie AR, Börnke F
Journal: Plant Physiology
Publisher: AMER SOC PLANT BIOLOGISTS
Publication year: 2011
Volume: 156
Journal issue: 4
Pages range: 1754-1771
ISSN: 0032-0889


Abstract


Trehalose-6-phosphate (T6P) is a signaling metabolite that regulates carbon metabolism, developmental processes, and growth in plants. In Arabidopsis (Arabidopsis thaliana), T6P signaling is, at least in part, mediated through inhibition of the SNF1-related protein kinase SnRK1. To investigate the role of T6P signaling in a heterotrophic, starch-accumulating storage organ, transgenic potato (Solanum tuberosum) plants with altered T6P levels specifically in their tubers were generated. Transgenic lines with elevated T6P levels (B33-TPS, expressing Escherichia coli osmoregulatory trehalose synthesis A [OtsA], which encodes a T6P synthase) displayed reduced starch content, decreased ATP contents, and increased respiration rate diagnostic for high metabolic activity. On the other hand, lines with significantly reduced T6P (B33-TPP, expressing E. coli OtsB, which encodes a T6P phosphatase) showed accumulation of soluble carbohydrates, hexose phosphates, and ATP, no change in starch when calculated on a fresh weight basis, and a strongly reduced tuber yield. [C-14] Glucose feeding to transgenic tubers indicated that carbon partitioning between starch and soluble carbohydrates was not altered. Transcriptional profiling of B33-TPP tubers revealed that target genes of SnRK1 were strongly up-regulated and that T6P inhibited potato tuber SnRK1 activity in vitro. Among the SnRK1 target genes in B33-TPP tubers, those involved in the promotion of cell proliferation and growth were down-regulated, while an inhibitor of cell cycle progression was up-regulated. T6P-accumulating tubers were strongly delayed in sprouting, while those with reduced T6P sprouted earlier than the wild type. Early sprouting of B33-TPP tubers correlated with a reduced abscisic acid content. Collectively, our data indicate that T6P plays an important role for potato tuber growth.



FAU Authors / FAU Editors

Börnke, Frederik PD Dr.
Lehrstuhl für Biochemie
Debast, Stefan Dr. rer. nat.
Lehrstuhl für Biochemie
Hofmann, Jörg Dr.
Lehrstuhl für Biochemie
Sonnewald, Uwe Prof. Dr.
Lehrstuhl für Biochemie


External institutions with authors

Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK) / Leibniz Institute of Plant Genetics and Crop Plant Research
Max-Planck-Institut für molekulare Pflanzenphysiologie / Max Planck Institute of Molecular Plant Physiology


How to cite

APA:
Debast, S., Nunes-Nesi, A., Hajirezaei, M.R., Hofmann, J., Sonnewald, U., Fernie, A.R., & Börnke, F. (2011). Altering Trehalose-6-Phosphate Content in Transgenic Potato Tubers Affects Tuber Growth and Alters Responsiveness to Hormones during Sprouting. Plant Physiology, 156(4), 1754-1771. https://dx.doi.org/10.1104/pp.111.179903

MLA:
Debast, Stefan, et al. "Altering Trehalose-6-Phosphate Content in Transgenic Potato Tubers Affects Tuber Growth and Alters Responsiveness to Hormones during Sprouting." Plant Physiology 156.4 (2011): 1754-1771.

BibTeX: 

Last updated on 2018-07-08 at 02:41