Skip Navigation


Plant and Cell Physiology Advance Access originally published online on July 16, 2009
Plant and Cell Physiology 2009 50(9):1651-1662; doi:10.1093/pcp/pcp108
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Data
Right arrow All Versions of this Article:
50/9/1651    most recent
pcp108v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Baroja-Fernández, E.
Right arrow Articles by Pozueta-Romero, J.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Baroja-Fernández, E.
Right arrow Articles by Pozueta-Romero, J.
Agricola
Right arrow Articles by Baroja-Fernández, E.
Right arrow Articles by Pozueta-Romero, J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2009. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oxfordjournals.org

Enhancing Sucrose Synthase Activity in Transgenic Potato (Solanum tuberosum L.) Tubers Results in Increased Levels of Starch, ADPglucose and UDPglucose and Total Yield

Edurne Baroja-Fernández1,5, Francisco José Muñoz1,5, Manuel Montero1, Ed Etxeberria1,2, María Teresa Sesma1, Miroslav Ovecka1,3, Abdellatif Bahaji1, Ignacio Ezquer1, Jun Li1, Salomé Prat4 and Javier Pozueta-Romero1,*

1Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
2IFAS Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, FL 33850, USA
3Institute of Botany, Slovak Academy of Sciences, Dubravska cesta 14, SK-84523 Bratislava, Slovakia
4Centro Nacional de Biotecnología, CSIC, Campus Universidad Autónoma de Madrid, c/Darwin 3, 28049 Madrid, Spain

*Corresponding author: E-mail, javier.pozueta{at}unavarra.es; Fax, +34-948232191.


  Abstract

Sucrose synthase (SuSy) is a highly regulated cytosolic enzyme that catalyzes the conversion of sucrose and a nucleoside diphosphate into the corresponding nucleoside diphosphate glucose and fructose. To determine the impact of SuSy activity in starch metabolism and yield in potato (Solanum tuberosum L.) tubers we measured sugar levels and enzyme activities in tubers of SuSy-overexpressing potato plants grown in greenhouse and open field conditions. We also transcriptionally characterized tubers of SuSy-overexpressing and -antisensed potato plants. SuSy-overexpressing tubers exhibited a substantial increase in starch, UDPglucose and ADPglucose content when compared with controls. Tuber dry weight, starch content per plant and total yield of SuSy-overexpressing tubers increased significantly over those of control plants. In contrast, activities of enzymes directly involved in starch metabolism in SuSy-overexpressing tubers were normal when compared with controls. Transcriptomic analyses using POCI arrays and the MapMan software revealed that changes in SuSy activity affect the expression of genes involved in multiple biological processes, but not that of genes directly involved in starch metabolism. These analyses also revealed a reverse correlation between the expressions of acid invertase and SuSy-encoding genes, indicating that the balance between SuSy- and acid invertase-mediated sucrolytic pathways is a major determinant of starch accumulation in potato tubers. Results presented in this work show that SuSy strongly determines the intracellular levels of UDPglucose, ADPglucose and starch, and total yield in potato tubers. We also show that enhancement of SuSy activity represents a useful strategy for increasing starch accumulation and yield in potato tubers.

Keywords: Carbohydrate metabolism

Abbreviations: ADPG, ADPglucose; SuSy, sucrose synthase; U, unit of enzyme activity; UDPG, UDPglucose.

5These authors contributed equally to this work.

(Received June 17, 2009; Accepted July 14, 2009)
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.