植物螯合肽的转运与功能研究进展

Research Advances of Phytochelatin Transport and Its Function

植物螯合肽(phytochelatins,PCs)是由植物螯合肽合酶催化谷胱甘肽合成的一类生物小分子,结构式为(γ-Glu-Cys)n-Gly(n=2～11),在真菌和高等植物耐受重金属胁迫机制中具有重要作用。近年来,人们在PC介导重金属脱毒害的分子机理研究上取得了重要进展,发现SpHMT1和SpABC2是PC在裂殖酵母中介导重金属液泡区室化的主要转运蛋白,鉴定了拟南芥液泡膜PC转运蛋白AtABCC1和AtABCC2。此外,PCs也可能在超积累植物细胞内对重金属脱毒害具有重要功能。

Phytochelatins （PCs） are synthesized by PC synthases from glutathione with the general structure of （γ-Glu-Cys）n-Gly （n=2-11）. They are necessary for heavy metal tolerance in fungi and higher plants. Recent studies have shown that both SpHMT1 and SpABC2 play an important role in PC-mediating heavy metal se- questration in the vacuole of Schizosaccharomycespombe, while AtABCCI and AtABCC2 are the major transporters for removing PC-heavy metal complexes from cytosol into the vacuole ofArabidopsis thaliana. In addition, several studies have suggested that PCs might detoxify heavy metal inside the cells ofhyperaccumulator.