植物对重金属镉的响应及其耐受机理

重金属Cd作为非必需微量元素,经根系吸收并累积时对植物具有很强的毒性,因而开展植物对Cd的响应途径及其调控机理研究,对改良植物对Cd的耐受性以及开发超累积植物均具有重要意义.植物硫代谢、抗氧化系统和Cdz2 跨膜运输是植物对重金属镉响应的主要途径,本研究综述了以上3种耐受机制的研究进展,包括Cd2 诱导植物硫转运蛋白、硫还原相关酶类以及半胱氮酸、谷胱廿肽和植物螯合肽合成及其基因表达调控,Cd2 诱发的植物抗氧化反应及其基因表达,质膜和液泡转运蛋白促进Cd2 运输和隔离的基因调控.

Response and resistance mechanisms of plants to cadmium

Cadmium is a non-essential micronutrient with strong phytotoxicity to plants when it is absorbed through the root system and accumulated in the plant tissues.It is important for improving the plants tolerance to cadmium and enabling a series of hyperaccumulation in plants.Sulfate metabolism,oxidation resistance systems and trans-membrane transport of cadmium are the main channels of plants response to cadmium.This article summarizes three kinds of mechanisms of heavy metal cadmium tolerance in plants,including cadmium-induced generation of sulfur transporters,sulfur reductase,cysteine,glutathione,phytochelatins,and gene expression and regulation.Cadmium-induced oxidation resistance response and gene expression,plasma and vacuole membrane transporters can accelerate the gene regulation of transport and isolation of cadmium.