植物重金属转运蛋白研究进展

Heavy metal-transport proteins in plants:A review

土壤中的有毒重金属不仅对植物有害,也可通过食物链危害人类和动物的健康.重金属转运蛋白在植物吸收、抵抗重金属的复杂机制中起着关键作用.植物重金属转运蛋白分为吸收蛋白和排出蛋白,其中,吸收蛋白转运必需重金属进入细胞,同时也会因为必需重金属的缺乏或离子之间的竞争而运载有毒重金属;排出蛋白是一类解毒蛋白,可将过量的或有毒的重金属逆向转运出细胞,或区室化于液泡中.目前,细胞内多种重金属转运蛋白基因的转录水平与重金属离子积累之间的联系已被揭示,并分离克隆出诸多相关蛋白家族成员.本文综述了近年来发现并鉴定的主要重金属转运蛋白的金属亲和性、器官表达特异性及细胞内定位等的研究进展.

The heavy metals in soil not only damage plant growth,but also threaten the health of human beings and animals through food chain.Heavy metal-transport proteins play crucial roles in the heavy metals uptake and tolerance of plants.Plant heavy metal-transport proteins can be classified as metal-uptake proteins and metal-efflux proteins.The metal-uptake proteins can transport essential heavy metals into cytoplasm,and also,transport toxic heavy metals into cytoplasm due to the absence of essential heavy metals or the competition among ions.The metal-efflux proteins are a group of detoxification proteins,which can efflux excess and toxic heavy metals from cytoplasm,or move these metals into vacuole.In recent years,the associations between elevated steady-state transcript levels of heavy metal-transporter genes and metal accumulation in plants have been revealed,and many heavy metal-transport proteins have been cloned and identified.In this paper,the metal affinity,tissue-specific gene expression,and cellular location of representative heavy metal-transport proteins were reviewed.