Titelangaben
Wojas, Sylwia ; Ruszczynska, Anna ; Bulska, Ewa ; Clemens, Stephan ; Antosiewicz, Danuta Maria:
The role of subcellular distribution of cadmium and phytochelatins in the generation of distinct phenotypes of AtPCS1- and CePCS3-expressing tobacco.
In: Journal of Plant Physiology.
Bd. 167
(2010)
Heft 12
.
- S. 981-988.
ISSN 0176-1617
DOI: https://doi.org/10.1016/j.jplph.2010.02.010
Abstract
Exposure to Cd2+ leads to activation of phytochelatin synthase (PCS) and the formation of phytochelatins (PCs) in the cytosol. Binding of Cd by PCs and the subsequent transport of PC–Cd complexes to the vacuoleare essential for Cd tolerance. Attempts to improve Cd detoxification by PCS overexpression have resulted in contrasting plant phenotypes, ranging from enhanced Cd tolerance to Cd hypersensitivity. In the present paper, changes in the subcellular phytochelatin, glutathione, -glutamylcysteine and cadmiumvacuolar and cytosolic distribution underlying these phenotypes were examined. Cadmium and PCs levels were determined in protoplasts and vacuoles isolated from leaves of Nicotiana tabacum expressing either of two phytochelatin synthase genes, AtPCS1 and CePCS (differing in their level of Cd tolerance;being Cd hypersensitive or more Cd-tolerant as compared to wild-type plants, respectively). We showed that Cd hypersensitivity of AtPCS1-expressing tobacco results from a significant decrease in both the cytosolic and vacuolar pool of PCs, indicating a decreased cadmium detoxification capacity. By contrast, enhanced Cd tolerance of CePCS plants was accompanied by an increased cytosolic and vacuolar SH ofPC/Cd ratio, suggesting more efficient Cd detoxification. Surprisingly, the substantially reduced level of PCs did not influence Cd accumulation in vacuoles of AtPCS1-transformed tobacco (relative to the wildtype),which suggests the important role of mechanisms other than PC–Cd transport in Cd translocationto the vacuole. Our data suggest that the key role of the PCs in Cd tolerance is temporary binding of Cd2+ in the cytosol, and contrary to the current view, their contribution to cadmium sequestration seems to be less important.
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | BAYCEER86047 |
Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie > Lehrstuhl Pflanzenphysiologie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie > Lehrstuhl Pflanzenphysiologie > Lehrstuhl Pflanzenphysiologie - Univ.-Prof. Dr. Stephan Clemens Forschungseinrichtungen > Forschungszentren > Bayreuther Zentrum für Ökologie und Umweltforschung - BayCEER Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie Forschungseinrichtungen Forschungseinrichtungen > Forschungszentren |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik |
Eingestellt am: | 18 Jun 2015 06:35 |
Letzte Änderung: | 18 Jun 2015 06:35 |
URI: | https://eref.uni-bayreuth.de/id/eprint/15168 |