Ecophysiology of metallophytes
Up to now, no investigations have detected any specific metabolites in metal-tolerant ecotypes. Metal tolerances are due to differential gene activities which are up- or down-regulating enzymes. In the case of metal uptake into the roots, there is a down-regulation of the high-affinity phosphate transporter in arsenic-tolerant plants Macnair amp Cumbes 1987 or the elevated expression of Zn transporter genes Assuncao et al. 2001 . Once the metal is in the cell, metal-tolerant plants have...