Skip Navigation

This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
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 (26)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Whittaker, A.
Right arrow Articles by Farrant, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Whittaker, A.
Right arrow Articles by Farrant, J.
Agricola
Right arrow Articles by Whittaker, A.
Right arrow Articles by Farrant, J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Journal of Experimental Botany, Vol. 52, No. 358, pp. 961-969, May 1, 2001
© 2001 Oxford University Press

Original Papers

Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation-tolerant species Sporobolus stapfianus and Xerophyta viscosa

Anne Whittaker1, Adriana Bochicchio2, Concetta Vazzana2, George Lindsey1 and Jill Farrant1,3

1 Department of Biochemistry, University of Cape Town, Private Bag Rondebosch 7700, South Africa
2 Dipartimento di Scienze Agronomiche e Gestione del Territorio Agroforestale; Università di Firenze, Piazzale delle Cascine 18, I-50144 Firenze, Italia

The phosphorylation of glucose and fructose is an important step in regulating the supply of hexose sugars for biosynthesis and metabolism. Changes in leaf hexokinase (EC 2.7.1.1) activity and in vivo metabolite levels were examined during drying in desiccation-tolerant Sporobolus stapfianus and Xerophyta viscosa. Leaf hexokinase activity was significantly induced from 85% to 29% relative water content (RWC) in S. stapfianus and from 89% to 55% RWC in X. viscosa. The increase in hexokinase corresponded to the region of sucrose accumulation in both species, with the highest activity levels coinciding with region of net glucose and fructose removal. The decline of hexose sugars and accumulation of sucrose in both plant species was not associated with a decline in acid and neutral invertase. The increase in hexokinase activity may be important to ensure that the phosphorylation and incorporation of glucose and fructose into metabolism exceeded production from potential hydrolytic activity. Total cellular glucose-6-phosphate (Glc-6-P) and fructose-6-phosphate (Fru-6-P) levels were held constant throughout dehydration. In contrast to hexokinase, fructokinase activity was unchanged during dehydration. Hexokinase activity was not fully induced in leaves of S. stapfianus dried detached from the plant, suggesting that the increase in hexokinase may be associated with the acquisition of desiccation-tolerance.

Key words: Desiccation-tolerant, fructokinase, hexokinase, metabolites, resurrection plants.


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
 J Exp BotHome page
I. Mulako, J. M. Farrant, H. Collett, and N. Illing
Expression of Xhdsi-1VOC, a novel member of the vicinal oxygen chelate (VOC) metalloenzyme superfamily, is up-regulated in leaves and roots during desiccation in the resurrection plant Xerophyta humilis (Bak) Dur and Schinz
J. Exp. Bot., October 1, 2008; 59(14): 3885 - 3901.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
A. Whittaker, T. Martinelli, J. M. Farrant, A. Bochicchio, and C. Vazzana
Sucrose phosphate synthase activity and the co-ordination of carbon partitioning during sucrose and amino acid accumulation in desiccation-tolerant leaf material of the C4 resurrection plant Sporobolus stapfianus during dehydration
J. Exp. Bot., October 1, 2007; 58(13): 3775 - 3787.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
T. Martinelli, A. Whittaker, A. Bochicchio, C. Vazzana, A. Suzuki, and C. Masclaux-Daubresse
Amino acid pattern and glutamate metabolism during dehydration stress in the 'resurrection' plant Sporobolus stapfianus: a comparison between desiccation-sensitive and desiccation-tolerant leaves
J. Exp. Bot., August 1, 2007; 58(11): 3037 - 3046.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
S. Peters, S. G. Mundree, J. A. Thomson, J. M. Farrant, and F. Keller
Protection mechanisms in the resurrection plant Xerophyta viscosa (Baker): both sucrose and raffinose family oligosaccharides (RFOs) accumulate in leaves in response to water deficit
J. Exp. Bot., June 1, 2007; 58(8): 1947 - 1956.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
C. Vander Willigen, N. W. Pammenter, S. G. Mundree, and J. M. Farrant
Mechanical stabilization of desiccated vegetative tissues of the resurrection grass Eragrostis nindensis: does a TIP 3;1 and/or compartmentalization of subcellular components and metabolites play a role?
J. Exp. Bot., March 1, 2004; 55(397): 651 - 661.
[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.