Overexpression of plastidial thioredoxin f leads to enhanced starch accumulation in tobacco leaves
Fecha
2013Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión publicada / Argitaratu den bertsioa
Impacto
|
10.1111/pbi.12052
Resumen
Starch, the most abundant storage carbohydrate in plants, has been a major feedstock for first‐generation biofuels. Growing fuel demands require, however, that the starch yields of energy crops be improved. Leaf starch is synthesised during the day and degraded at night to power nonphotosynthetic metabolism. Redox regulation has been associated with the coordination of the enzymes involved in sta ...
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Starch, the most abundant storage carbohydrate in plants, has been a major feedstock for first‐generation biofuels. Growing fuel demands require, however, that the starch yields of energy crops be improved. Leaf starch is synthesised during the day and degraded at night to power nonphotosynthetic metabolism. Redox regulation has been associated with the coordination of the enzymes involved in starch metabolism, but neither the signals nor mechanisms that regulate this metabolism are entirely clear. In this work, the thioredoxin (Trx) f and m genes, which code for key enzymes in plastid redox regulation, were overexpressed from the plastid genome. Tobacco plants overexpressing Trx f, but not Trx m, showed an increase of up to 700% in leaf starch accumulation, accompanied by an increase in leaf sugars, specific leaf weight (SLW), and leaf biomass yield. To test the potential of these plants as a nonfood energy crop, tobacco leaves overexpressing Trx f were subjected to enzymatic hydrolysis, and around a 500% increase in the release of fermentable sugars was recorded. The results show that Trx f is a more effective regulator of photosynthetic carbon metabolism in planta than Trx m. The overexpression of Trx f might therefore provide a means of increasing the carbohydrate content of plants destined for use in biofuel production. It might also provide a means of improving the nutritional properties of staple food crops. [--]
Materias
Chloroplast,
Transformation,
Tobacco,
Thioredoxin,
Starch,
Bioethanol feedstock
Editor
Wiley
Publicado en
Plant Biotechnology Journal (2013) 11, pp. 618–627
Departamento
Universidad Pública de Navarra/Nafarroako Unibertsitate Publikoa. IdAB. Instituto de Agrobiotecnología / Agrobioteknologiako Institutua
Versión del editor
Entidades Financiadoras
This work was supported by grants from Gobierno de Navarra (IIM10865.RI1) and Ministerio de Ciencia e Innovación (AGL2010-15107). R.S.-B. and P.M.-C. were supported by predoctoral fellowships from CSIC and G.Valenciana (Spain), respectively.