Identification of genes involved in metal transport in plants.

Plants obtain mineral nutrients from the soil. If they are growing in soil with high levels of metals, they will take up an excess of what is needed for growth. Depending on the species, this can be detrimental to growth—or lethal—and can greatly limit the growth range of plants and the productivity of agricultural species. However, some plants have adapted to living in soil containing excess metals. A portion of these species will even hyperaccumulate the metals, leading to exceedingly high levels of metals in the plant tissues. The metal most commonly accumulated is nickel (Ni). How and why certain plants are able to accumulate—and tolerate—high levels of potentially toxic compounds has spawned diverse areas of research, including an article by Talke et al., ‘‘Zincdependent global transcriptional control, transcriptional deregulation, and higher gene copy number for genes in metal homeostasis of the hyperaccumulator Arabidopsis halleri,’’ which appeared in the September 2006 issue of Plant Physiology.