超富集植物吸收富集重金属的生理和分子生物学机制

与普通植物相比，超富集植物在地上部富集大量重金属离子的情况下可以正常生长，其富集重金属的机理已经成为当前植物逆境生理研究的热点领域．尤其是近两年，随着分子生物学等现代技术手段的引人，关于重金属离子富集机理的研究取得了一定进展．通过与酵母突变株功能互补克隆到了多条编码微量元素转运蛋白的全长cDNA；也从分子水平上研究了谷胱甘肽、植物螯合素、金属硫蛋白、有机酸或氨基酸等含巯基物质与重金属富集之间的可能关系．本文从植物生理和分子生物学角度简要评述超富集植物对重金属元素的吸收、富集、整合及区室化的机制．

Physiological and molecular biological mechanisms of heavy metal absorption and accumulation in hyperaccumualtors

In comparison with normal plants, hyperaccumulators have the ability to accumulate heavy metals in their shoots far exceeding those observed in soil, without suffering from detrimental effects.With the help of molecular technologies, the research on the mechanisms of heavy metal accumulation in hyperaccumulators has been made a great progress. A number of trace element transporters have been cloned by functional complementation with yeast mutants defective in metal absorption. The relations between glutathione, phytochelatins metallothioneins, organic acids and heavy metals have been studied by molecular technologies. This review concentrated on the physiological and molecular mechanisms of heavy metal absorption and sequestration in hyperaccumulators.