Leaf starch turnover occurs in long days and in falling light at the end of the day
| Autor: | Gavin M. George, Anna Flis, Alison M. Smith, Regina Feil, Stéphanie Arrivault, Dean Sumner, John E. Lunn, Virginie Mengin, Mark Stitt, Olivier Fernandez, Hirofumi Ishihara, Samuel C. Zeeman |
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| Přispěvatelé: | John Innes Centre, Max Planck Institute of Molecular Plant Physiology (MPI-MP), Max-Planck-Gesellschaft, Swiss Fed Inst Technol, Plant Biochem, CH-8092 Zurich, Switzerland, Partenaires INRAE, Research School of Biology, Australian National University (ANU), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Université de Lyon (COMUE), European Commission Collaborative Project TiMet [245143], BBSRC Institute Strategic Programme [BB/J004561/1], Max-Planck Society, Germany, ETH (Zurich), SystemsX (Switzerland) grant |
| Předmět: |
0106 biological sciences
0301 basic medicine trehalose 6-phosphate Physiology Starch enzyme-activities [SDV]Life Sciences [q-bio] Circadian clock Plant Science Photosynthesis 01 natural sciences 03 medical and health sciences chemistry.chemical_compound Animal science Botany Genetics Arabidopsis thaliana 2. Zero hunger photoperiodism sugar-beet leaves biology beta-vulgaris l fungi Plant physiology food and beverages Maltose biology.organism_classification carbohydrate-metabolism transitory starch Light intensity 030104 developmental biology adp-glucose pyrophosphorylase diurnal changes chemistry carbon allocation sense organs arabidopsis circadian clock 010606 plant biology & botany |
| Zdroj: | University of Helsinki Plant Physiology Plant Physiology, American Society of Plant Biologists, 2017, 174 (4), pp.2199-2212. ⟨10.1104/pp.17.00601⟩ |
| ISSN: | 0032-0889 1532-2548 |
| Popis: | International audience; We investigated whether starch degradation occurs at the same time as starch synthesis in Arabidopsis (Arabidopsis thaliana) leaves in the light. Starch accumulated in a linear fashion for about 12 h after dawn, then accumulation slowed and content plateaued. Following decreases in light intensity, the rate of accumulation of starch declined in proportion to the decline in photosynthesis if the decrease occurred, 10 h after dawn, but accumulation ceased or loss of starch occurred if the same decrease in light intensity was imposed more than 10 h after dawn. These changes in starch accumulation patterns after prolonged periods in the light occurred at both high and low starch contents and were not related to time-dependent changes in either the rate of photosynthesis or the partitioning of assimilate between starch and Suc, as assessed from metabolite measurements and (CO2)-C-14 pulse experiments. Instead, measurements of incorporation of C-13 from (CO2)-C-13 into starch and of levels of the starch degradation product maltose showed that substantial starch degradation occurred simultaneously with synthesis at time points > 14 h after dawn and in response to decreases in light intensity that occurred > 10 h after dawn. Starch measurements in circadian clock mutants suggested that the clock influences the timing of onset of degradation. We conclude that the propensity for leaf starch to be degraded increases with time after dawn. The importance of this phenomenon for efficient use of carbon for growth in long days and for prevention of starvation during twilight is discussed. |
| Databáze: | OpenAIRE |
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