title: Ability of transgenic poplars with elevated glutathione content to tolerate zinc(2+) stress.
abstract: Phytoremediation potentials of four poplar lines, Populus nigra (N-SL clone), Populus canescens, and two transgenic P. canescens clones were investigated using in vitro leaf discs cultures. The transgenic poplars overexpressed a bacterial gene encoding gamma-glutamylcysteine synthetase in the cytosol (11ggs) or in the chlopoplasts (6LgI), and therefore, they contained an elevated level of glutathione. Leaf discs of poplar clones were exposed to different concentrations of ZnSO(4) for 21 days. Zinc(2+) was phytotoxic only at high concentrations (10(-2) to 10(-1) M) at all P. canescens lines, but P. nigra was more sensitive. Transgenic poplars showed elevated heavy metal uptake as compared to the nontransformed clones. Treatments with zinc(2+) strongly induced the activity of glutathione S-transferase enzyme in untransformed poplar lines but to a lesser extent in the transgenic clones. These results suggest that transgenic poplars are more suitable for phytoremediation of soils contaminated with zinc(2+) than wild-type plants.
authors.affiliation: Department of Genetics and Plant Breeding, HAS-SIU, Szent István University, 2103 Gödöllö, Páter K. u. 1, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Bittsánszky
authors.forename: Tamás
authors.initials: T
authors.lastname: Kömives
authors.forename: Gábor
authors.initials: G
authors.lastname: Gullner
authors.forename: Gábor
authors.initials: G
authors.lastname: Gyulai
authors.forename: József
authors.initials: J
authors.lastname: Kiss
authors.forename: László
authors.initials: L
authors.lastname: Heszky
authors.forename: László
authors.initials: L
authors.lastname: Radimszky
authors.forename: Heinz
authors.initials: H
authors.lastname: Rennenberg
mesh_terms: D000222:Adaptation, Physiological; D001673:Biodegradation, Environmental; D004351:Drug Resistance; D005721:Glutamate-Cysteine Ligase / Q000235:genetics / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism*; D005982:Glutathione Transferase / Q000235:genetics / Q000494:pharmacology; D030821:Plants, Genetically Modified; D032107:Populus / Q000235:genetics* / Q000502:physiology*; D015032:Zinc / Q000494:pharmacology* / Q000633:toxicity*
chemical_list: D005982:Glutathione Transferase; D005721:Glutamate-Cysteine Ligase; D005978:Glutathione; D015032:Zinc