Senescence-inducible cell wall and intracellular purple acid phosphatases: implications for phosphorus remobilization in Hakea prostrata (Proteaceae) and Arabidopsis thaliana (Brassicaceae)
| العنوان: | Senescence-inducible cell wall and intracellular purple acid phosphatases: implications for phosphorus remobilization in Hakea prostrata (Proteaceae) and Arabidopsis thaliana (Brassicaceae) |
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| المؤلفون: | William C. Plaxton, Kyla A. Stigter, Eric T. Fedosejevs, Michael W. Shane |
| المصدر: | Journal of Experimental Botany |
| بيانات النشر: | Oxford University Press, 2014. |
| سنة النشر: | 2014 |
| مصطلحات موضوعية: | 0106 biological sciences, Hakea, Hakea prostrata, Cytoplasm, Arabidopsis thaliana, Physiology, Acid Phosphatase, Arabidopsis, Plant Science, 01 natural sciences, Models, Biological, Plant Roots, Proteaceae, Phosphates, Cell wall, 03 medical and health sciences, Ribonucleases, Cell Wall, Gene Expression Regulation, Plant, cell wall hydrolases, purple acid phosphatase, phosphorus remobilization, Cellular Senescence, 030304 developmental biology, Glycoproteins, Plant Proteins, Plant senescence, 0303 health sciences, biology, senescence, Phosphorus, biology.organism_classification, Up-Regulation, Plant Leaves, Biochemistry, Seedlings, Vacuoles, ribonuclease, Cell aging, Intracellular, 010606 plant biology & botany, Research Paper |
| الوصف: | Summary Targeting of senescence-inducible acid phosphatases and RNases to the cell wall and vacuolar compartments appears to make a crucial contribution to efficient P remobilization networks of senescing tissues of Hakea prostrata and Arabidopsis. Despite its agronomic importance, the metabolic networks mediating phosphorus (P) remobilization during plant senescence are poorly understood. Highly efficient P remobilization (~85%) from senescing leaves and proteoid roots of harsh hakea (Hakea prostrata), a native ‘extremophile’ plant of south-western Australia, was linked with striking up-regulation of cell wall-localized and intracellular acid phosphatase (APase) and RNase activities. Non-denaturing PAGE followed by in-gel APase activity staining revealed senescence-inducible 120kDa and 60kDa intracellular APase isoforms, whereas only the 120kDa isoform was detected in corresponding cell wall fractions. Kinetic and immunological properties of the 120kDa and 60kDa APases partially purified from senescing leaves indicated that they are purple acid phosphatases (PAPs). Results obtained with cell wall-targeted hydrolases of harsh hakea were corroborated using Arabidopsis thaliana in which an ~200% increase in cell wall APase activity during leaf senescence was paralleled by accumulation of immunoreactive 55kDa AtPAP26 polypeptides. Senescing leaves of an atpap26 T-DNA insertion mutant displayed a >90% decrease in cell wall APase activity. Previous research established that senescing leaves of atpap26 plants exhibited a similar reduction in intracellular (vacuolar) APase activity, while displaying markedly impaired P remobilization efficiency and delayed senescence. It is hypothesized that up-regulation and dual targeting of PAPs and RNases to the cell wall and vacuolar compartments make a crucial contribution to highly efficient P remobilization that dominates the P metabolism of senescing tissues of harsh hakea and Arabidopsis. To the best of the authors’ knowledge, the apparent contribution of cell wall-targeted hydrolases to remobilizing key macronutrients such as P during senescence has not been previously suggested. |
| اللغة: | English |
| تدمد: | 1460-2431 0022-0957 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::33b00f51611fd2566036e6f3af6c9ba9Test http://europepmc.org/articles/PMC4203141Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....33b00f51611fd2566036e6f3af6c9ba9 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14602431 00220957 |
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