Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa.
| dc.contributor.author | Whittaker, Anne | |
| dc.contributor.author | Bochicchio, Adriana | |
| dc.contributor.author | Vazzana, Concetta | |
| dc.contributor.author | Lindsey, George | |
| dc.contributor.author | Farrant, Jill | |
| dc.date.accessioned | 2016-08-04T09:10:50Z | |
| dc.date.available | 2016-08-04T09:10:50Z | |
| dc.date.issued | 2001 | |
| dc.date.updated | 2016-08-04T07:46:53Z | |
| dc.description.abstract | 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. | en_ZA |
| dc.identifier | http://dx.doi.org/10.1093/jexbot/52.358.961 | |
| dc.identifier.apacitation | Whittaker, A., Bochicchio, A., Vazzana, C., Lindsey, G., & Farrant, J. (2001). Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa. <i>Journal of Experimental Botany</i>, http://hdl.handle.net/11427/21108 | en_ZA |
| dc.identifier.chicagocitation | Whittaker, Anne, Adriana Bochicchio, Concetta Vazzana, George Lindsey, and Jill Farrant "Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa." <i>Journal of Experimental Botany</i> (2001) http://hdl.handle.net/11427/21108 | en_ZA |
| dc.identifier.citation | Whittaker, A., Bochicchio, A., Vazzana, C., Lindsey, G., & Farrant, J. (2001). Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation‐tolerant species Sporobolus stapfianus and Xerophyta viscosa. Journal of Experimental Botany, 52(358), 961-969. | en_ZA |
| dc.identifier.issn | 0022-0957 | en_ZA |
| dc.identifier.ris | TY - Journal Article AU - Whittaker, Anne AU - Bochicchio, Adriana AU - Vazzana, Concetta AU - Lindsey, George AU - Farrant, Jill AB - 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. DA - 2001 DB - OpenUCT DP - University of Cape Town J1 - Journal of Experimental Botany LK - https://open.uct.ac.za PB - University of Cape Town PY - 2001 SM - 0022-0957 T1 - Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa TI - Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa UR - http://hdl.handle.net/11427/21108 ER - | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11427/21108 | |
| dc.identifier.vancouvercitation | Whittaker A, Bochicchio A, Vazzana C, Lindsey G, Farrant J. Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa. Journal of Experimental Botany. 2001; http://hdl.handle.net/11427/21108. | en_ZA |
| dc.language | eng | en_ZA |
| dc.publisher | Oxford University Press | en_ZA |
| dc.publisher.institution | University of Cape Town | |
| dc.source | Journal of Experimental Botany | en_ZA |
| dc.source.uri | http://www.oxfordjournals.org/our_journals/exbotj/openaccess.html | |
| dc.subject.other | Desiccation‐tolerant | |
| dc.subject.other | fructokinase | |
| dc.subject.other | hexokinase | |
| dc.subject.other | metabolites | |
| dc.subject.other | resurrection plants | |
| dc.title | Changes in leaf hexokinase activity and metabolite levels in response to drying in the desiccation?tolerant species Sporobolus stapfianus and Xerophyta viscosa. | en_ZA |
| dc.type | Journal Article | en_ZA |
| uct.type.filetype | Text | |
| uct.type.filetype | Image | |
| uct.type.publication | Research | en_ZA |
| uct.type.resource | Article | en_ZA |