Skip Navigation


Plant and Cell Physiology Advance Access originally published online on February 13, 2008
Plant and Cell Physiology 2008 49(3):469-480; doi:10.1093/pcp/pcn022
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Data
Right arrow All Versions of this Article:
49/3/469    most recent
pcn022v1
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 ISI Web of Science
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 arrow Search for citing articles in:
ISI Web of Science (1)
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Müller, G. L.
Right arrow Articles by Lara, M. V.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Müller, G. L.
Right arrow Articles by Lara, M. V.
Agricola
Right arrow Articles by Müller, G. L.
Right arrow Articles by Lara, M. V.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2008. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oxfordjournals.org

Nicotiana tabacum NADP-Malic Enzyme: Cloning, Characterization and Analysis of Biological Role

Gabriela Leticia Müller, María Fabiana Drincovich, Carlos Santiago Andreo* and María Valeria Lara

Centro de Estudios Fotosintéticos y Bioquímicos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Suipacha 531, Rosario (2000), Argentina

*Corresponding author: E-mail, carlosandreo{at}cefobi.gov.ar; Fax, +54-341-4370044.


  Abstract

NADP-malic enzyme (NADP-ME) catalyzes the oxidative decarboxylation of L-malate, producing pyruvate, CO2 and NADPH. The photosynthetic role of this enzyme in C4 and Crassulacean acid metabolism (CAM) plants has been well established; however, the biological role of several non-photosynthetic isoforms described in C3, C4 and CAM plants is still speculative. In this study, the characterization of the NADP-ME isoforms from Nicotiana tabacum was performed. Three different nadp-me transcripts were identified in this C3 plant, two of which encode for putative cytosolic isoforms (DQ923118 [GenBank] and EH663836 [GenBank] ), while the third encodes for a plastidic counterpart (DQ923119 [GenBank] ). Although the three transcripts are expressed in vegetative as well as in reproductive tissues, they display different levels of expression. With regards to enzyme activity, root is the tissue that displays the highest NADP-ME activity. Recombinant NADP-MEs encoded by DQ923118 [GenBank] and DQ923119 [GenBank] were expressed in Escherichia coli and their kinetic parameters and response to different metabolic effectors were analyzed. Studies carried out with crude extracts and with the recombinant proteins indicate that the cytosolic and plastidic isoforms aggregate as tetramers of subunits of 65 and 63 kDa, respectively. Real-time reverse transcription–PCR studies show that the three nadp-me tobacco transcripts respond differently to several biotic and abiotic stress stimuli. Finally, the physiological role of each isoform is discussed in terms of the occurrence, kinetic properties and response to stress. The structure of the NADP-ME family in tobacco is compared with those of other C3 species.

Keywords: NADP-malic enzyme - Nicotiana tabacum - Stress - Tobacco

Abbreviations: BSC, bundle sheath cell; CAM, Crassulacean acid metabolism; IEF, isoelectric focusing; NADP–ME, NADP-malic enzyme; OAA, oxaloacetic acid; PEG, polyethylene glycol; PEPC, phosphoenolpyruvate carboxylase; RT–PCR, reverse transcription–PCR

(Received January 4, 2008; Accepted February 6, 2008)
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Gen Biol EvolHome page
P.-A. Christin, E. Samaritani, B. Petitpierre, N. Salamin, and G. Besnard
Evolutionary Insights on C4 Photosynthetic Subtypes in Grasses from Genomics and Phylogenetics
Gen Biol Evol, August 13, 2009; 2009(0): 221 - 230.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
J. Borsani, C. O. Budde, L. Porrini, M. A. Lauxmann, V. A. Lombardo, R. Murray, C. S. Andreo, M. F. Drincovich, and M. V. Lara
Carbon metabolism of peach fruit after harvest: changes in enzymes involved in organic acid and sugar level modifications
J. Exp. Bot., April 1, 2009; 60(6): 1823 - 1837.
[Abstract] [Full Text] [PDF]


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.