植物中镉及其螯合物相关转运蛋白研究进展

The Studies on Cadmium and Its Chelate Related Transporters in Plants

镉是一种毒性极强的重金属污染物,土壤和大气中的镉通过植物根和叶的吸收在其体内积累。镉不仅影响植物的正常生理代谢过程,严重降低作物产量和品质,还可通过食物链的传递和富集危害人类身体健康。镉胁迫条件下植物会通过一系列的生理反应来减轻镉损伤,其中镉及其螯合物相关转运蛋白在植物抗镉毒害中起重要作用。金属转运蛋白是一类位于植物组织膜上的运输蛋白,其参与金属元素的吸收、转运和区隔过程。目前利用基因工程和现代分子生物学技术,已经鉴定出一系列镉及其螯合物相关转运蛋白,主要包括锌/铁转运蛋白(ZIP)、天然抗性相关巨噬细胞蛋白(NRAMP)、重金属ATP酶(HMA)、金属耐受蛋白(MTP)、阳离子交换体(CAX)、ATP结合盒转运蛋白(ABC)、黄色条纹转运蛋白(YSL)等家族。本文从植物细胞、亚细胞水平综述与镉吸收和转运相关的转运蛋白的分子生物学研究进展,为更好地了解镉在植物体内的差异积累原理、植物抗镉毒害机理和植物吸收转运镉的分子机制提供理论依据。

Cadmium is a highly toxic heavy metal pollutant. Cadmium from soil and atmospheric is accumulated in plant through the absorption of roots or leaves. Cadmium not only affects the physiological metabolism of plants, and reduces crop yield and quality seriously, but also endangers human health through the transmission and enrichment of food chain. Plant can alleviate cadmium damage through a series of physiological responses under cadmium stress, and cadmium and its chelate related transporters play an important role in plant resistance to cadmium toxicity. Metal transporters are a class of transport proteins located on the membrane which participate in the absorption, transport and segregation of metal elements. At present, a series of transporter proteins related to cadmium and its chelate have been identified by genetic engineering and molecular biology techniques, including Zrt/Irt-like Protein（ZIP）, Natural Resistance Associated Macrophage Protein（NRAMP）, Heavy Metal ATPase（HMA）, Metal Tolerance Protein（MTP）, Cation Exchanger（CAX）, ATP-binding Cassette Transporters（ABC）, Yellow Stripe-Like Transporter（YSL） and other families. This paper focuses on the progress of molecular biology of the transporters associated with cadmium absorption and transport on the cellular and subcellular levels. In order to provide a basis for better understanding of the cadmium accumulation in plants, plant resistance to cadmium toxicity and the molecular mechanism of cadmium uptake.