植物重金属超富集机理研究进展

植物超富集重金属机理主要涉及植物对金属离子高的吸收、运输能力，区域化作用及螯合作用等方面，其中跨膜运载蛋白的表达、调控对重金属超富集这一特性起了关键作用。金属阳离子运载蛋白家族主要包括CDF家族、NRAMP家族和ZIP家族等，在超富集植物中已克隆出多个家族的金属运载蛋白基因，这些基因的过量表达对重金属在细胞中的运输、分布和富集及提高植物的抗性方面发挥了重要作用。综述了近年来研究重金属超富集植物吸收、转运和贮存Zn、Ni、Cd等重金属的生理和分子机制所取得的主要进展。

Advances in research of mechanisms of heavy metal hyperaccumulation in plants

The mechanism of heavy metal hyperaccumulation were very complicated and involved various metabolic processes in plants.The recent studies showed that the high ability of metal ion uptaking and trafficking,compartmentalization in vacuole,cell wall or trichome,and the chelation with organic acid (such as citrate,malate and oxalate) or amino acid (histidine) were involved in the metal accumulation and tolerance mechanism in hyperaccumulation.In addition,several metal cation transmembrane transporter genes were cloned and characterized in hyperaccumulator,which belong to the CDF family,or NRAMP family and/or ZIP family.The overexpression of the metal ion transporter genes play important roles not only in heavy metal uptaking,trafficking,distribution and accumulation in the cell,but also in increase the heavy metal tolerance of hyperaccumulator.