Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum)
Nitrogen (N) remobilization in wheat (Triticum aestivum) plants is crucial because it determines the grain protein concentration and the baking quality of flour. In order to evaluate the influence of cytokinins on N remobilization during N starvation, we analyzed various N remobilization parameters...
Guardado en:
| Autores principales: | , , , , |
|---|---|
| Formato: | JOUR |
| Materias: | |
| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_01761617_v166_n16_p1775_Criado |
| Aporte de: |
| id |
todo:paper_01761617_v166_n16_p1775_Criado |
|---|---|
| record_format |
dspace |
| spelling |
todo:paper_01761617_v166_n16_p1775_Criado2023-10-03T15:08:02Z Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) Criado, M.V. Caputo, C. Roberts, I.N. Castro, M.A. Barneix, A.J. Benzylaminopurine Chloroplast Nitrogen remobilization Nitrogen starvation Triticum aestivum cytokinin nitrogen primer DNA article chloroplast electron microscopy growth, development and aging metabolism nucleotide sequence physiology polymerase chain reaction ultrastructure wheat Base Sequence Chloroplasts Cytokinins DNA Primers Microscopy, Electron Nitrogen Polymerase Chain Reaction Triticum Triticum aestivum Nitrogen (N) remobilization in wheat (Triticum aestivum) plants is crucial because it determines the grain protein concentration and the baking quality of flour. In order to evaluate the influence of cytokinins on N remobilization during N starvation, we analyzed various N remobilization parameters in wheat plants that were watered with 6-benzylaminopurine (BAP) either with or without KNO3. Besides, the effects of BAP on protein synthesis were evaluated, and the size and ultrastructure of chloroplasts of BAP-treated plants were studied. BAP supply inhibited N remobilization of plants independently of N supply as shown by the increase in protein, Rubisco, chlorophyll, sugar and starch concentrations in the older leaves, the decrease in amino acid and sugar export to the phloem, and the decrease in protein, Rubisco and chlorophyll concentrations in the younger leaves. Besides, BAP supply increased nitrate reductase activity and decreased nitrate concentration, thus suggesting an increased assimilatory capacity. The increase in protein concentration could be explained mainly by a significant decrease in protein degradation and, to a lesser extent, by an increase in protein synthesis. Finally, an increase both in the size of the chloroplast and in the plastoglobuli and starch contents in BAP-supplied plants was observed. We propose that cytokinins retain the sink activity of the older leaves by inhibiting amino acid and sugar export to the phloem and stimulating assimilate accumulation in the chloroplasts of the older leaves. Besides, BAP may increase protein concentration of the older leaves both by decreasing protein degradation and maintaining protein synthesis even under stress conditions. © 2009 Elsevier GmbH. All rights reserved. Fil:Criado, M.V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Roberts, I.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Castro, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Barneix, A.J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_01761617_v166_n16_p1775_Criado |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Benzylaminopurine Chloroplast Nitrogen remobilization Nitrogen starvation Triticum aestivum cytokinin nitrogen primer DNA article chloroplast electron microscopy growth, development and aging metabolism nucleotide sequence physiology polymerase chain reaction ultrastructure wheat Base Sequence Chloroplasts Cytokinins DNA Primers Microscopy, Electron Nitrogen Polymerase Chain Reaction Triticum Triticum aestivum |
| spellingShingle |
Benzylaminopurine Chloroplast Nitrogen remobilization Nitrogen starvation Triticum aestivum cytokinin nitrogen primer DNA article chloroplast electron microscopy growth, development and aging metabolism nucleotide sequence physiology polymerase chain reaction ultrastructure wheat Base Sequence Chloroplasts Cytokinins DNA Primers Microscopy, Electron Nitrogen Polymerase Chain Reaction Triticum Triticum aestivum Criado, M.V. Caputo, C. Roberts, I.N. Castro, M.A. Barneix, A.J. Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) |
| topic_facet |
Benzylaminopurine Chloroplast Nitrogen remobilization Nitrogen starvation Triticum aestivum cytokinin nitrogen primer DNA article chloroplast electron microscopy growth, development and aging metabolism nucleotide sequence physiology polymerase chain reaction ultrastructure wheat Base Sequence Chloroplasts Cytokinins DNA Primers Microscopy, Electron Nitrogen Polymerase Chain Reaction Triticum Triticum aestivum |
| description |
Nitrogen (N) remobilization in wheat (Triticum aestivum) plants is crucial because it determines the grain protein concentration and the baking quality of flour. In order to evaluate the influence of cytokinins on N remobilization during N starvation, we analyzed various N remobilization parameters in wheat plants that were watered with 6-benzylaminopurine (BAP) either with or without KNO3. Besides, the effects of BAP on protein synthesis were evaluated, and the size and ultrastructure of chloroplasts of BAP-treated plants were studied. BAP supply inhibited N remobilization of plants independently of N supply as shown by the increase in protein, Rubisco, chlorophyll, sugar and starch concentrations in the older leaves, the decrease in amino acid and sugar export to the phloem, and the decrease in protein, Rubisco and chlorophyll concentrations in the younger leaves. Besides, BAP supply increased nitrate reductase activity and decreased nitrate concentration, thus suggesting an increased assimilatory capacity. The increase in protein concentration could be explained mainly by a significant decrease in protein degradation and, to a lesser extent, by an increase in protein synthesis. Finally, an increase both in the size of the chloroplast and in the plastoglobuli and starch contents in BAP-supplied plants was observed. We propose that cytokinins retain the sink activity of the older leaves by inhibiting amino acid and sugar export to the phloem and stimulating assimilate accumulation in the chloroplasts of the older leaves. Besides, BAP may increase protein concentration of the older leaves both by decreasing protein degradation and maintaining protein synthesis even under stress conditions. © 2009 Elsevier GmbH. All rights reserved. |
| format |
JOUR |
| author |
Criado, M.V. Caputo, C. Roberts, I.N. Castro, M.A. Barneix, A.J. |
| author_facet |
Criado, M.V. Caputo, C. Roberts, I.N. Castro, M.A. Barneix, A.J. |
| author_sort |
Criado, M.V. |
| title |
Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) |
| title_short |
Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) |
| title_full |
Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) |
| title_fullStr |
Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) |
| title_full_unstemmed |
Cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (Triticum aestivum) |
| title_sort |
cytokinin-induced changes of nitrogen remobilization and chloroplast ultrastructure in wheat (triticum aestivum) |
| url |
http://hdl.handle.net/20.500.12110/paper_01761617_v166_n16_p1775_Criado |
| work_keys_str_mv |
AT criadomv cytokinininducedchangesofnitrogenremobilizationandchloroplastultrastructureinwheattriticumaestivum AT caputoc cytokinininducedchangesofnitrogenremobilizationandchloroplastultrastructureinwheattriticumaestivum AT robertsin cytokinininducedchangesofnitrogenremobilizationandchloroplastultrastructureinwheattriticumaestivum AT castroma cytokinininducedchangesofnitrogenremobilizationandchloroplastultrastructureinwheattriticumaestivum AT barneixaj cytokinininducedchangesofnitrogenremobilizationandchloroplastultrastructureinwheattriticumaestivum |
| _version_ |
1807317268558774272 |