Ca super(2) super(+)-dependent plant response to Pb super(2) super(+) is regulated by LCT1

• Published in: Environmental pollution (1987) 2007-06, Vol.147 (3), p.584-592
• Main Authors: Wojas, S, Ruszczynska, A, Bulska, E, Wojciechowski, M, Antosiewicz, D M
• Format: Article
• Language: English
• ISSN: 0269-7491
• DOI: 10.1016/j.envpol.2006.10.012

Tobacco plants transformed with TaLCT1 were cultured on Knop's medium with modified calcium concentrations (0.01-3mM) in the presence of Pb super(2) super(+), and in soil contaminated by lead. A 4-5kM Pb super(2) super(+) administered in the presence of 1mM Ca super(2) super(+) inhibited the root growth of transgenic plants to much lesser degree than of control plants, whereas in the presence of 3mM Ca super(2) super(+) no differences were found between the studied lines. The reduction of Pb super(2) super(+) toxicity in the presence of 1mM Ca super(2) super(+) was not accompanied by a change in the lead tissue concentration. However, when Ca super(2) super(+) level in the medium was lowered to 0.01mM, several fold higher root/shoot Pb ratio in transgenic plants was observed, twofold increase in the total amount of metal accumulated, and lower concentration of Pb in the xylem sap. Results suggest the involvement of TaLCT1 in the regulation of Ca-dependent Pb-detoxification, and under conditions of low calcium in lead uptake and distribution.