Key Laboratory of Horticulture Science for Southern Mountainous Regions, the Ministry of Education, College of Horticulture and Landscape Architecture, Southwest University, Beibei, Chongqing 400715, China.
State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing 400715, China.
Genes (Basel). 2022 Dec 19;13(12):2413. doi: 10.3390/genes13122413.
Metallothionein (MT) is a multifunctional inducible protein in animals, plants, and microorganisms. MT is rich in cysteine residues (10-30%), can combine with metal ions, has a low molecular weight, and plays an essential biological role in various stages of the growth and development of organisms. Due to its strong ability to bind metal ions and scavenge free radicals, metallothionein has been used in medicine, health care, and other areas. Zinc is essential for plant growth, but excessive zinc (Zn) is bound to poison plants, and cadmium (Cd) is a significant environmental pollutant. A high concentration of cadmium can significantly affect the growth and development of plants and even lead to plant death. In this study, the human metallothionein gene under the control of the CaMV 35S constitutive promoter was transformed into tobacco, and the tolerance and accumulation capacity of transgenic tobacco plants to Zn and Cd were explored. The results showed that the high-level expression of in tobacco could significantly enhance the accumulation of Zn and Cd in both the aboveground parts and the roots compared to wild-type tobacco plants and conferred a greater tolerance to Zn and Cd in transgenic tobacco. Subcellular localization showed that was localized to the nucleus and cytoplasm in the tobacco. Our study suggests that can be used for the phytoremediation of soil for heavy metal removal.
金属硫蛋白（MT）是动物、植物和微生物中一种具有多功能的诱导蛋白。MT 富含半胱氨酸残基（10-30%），可以与金属离子结合，分子量低，在生物体生长发育的各个阶段都发挥着重要的生物学作用。由于其结合金属离子和清除自由基的能力很强，金属硫蛋白已被应用于医学、保健等领域。锌是植物生长所必需的，但过量的锌（Zn）会毒害植物，而镉（Cd）是一种重要的环境污染物。高浓度的镉会显著影响植物的生长和发育，甚至导致植物死亡。在本研究中，受 CaMV 35S 组成型启动子控制的人金属硫蛋白基因被转入烟草中，探索了转基因烟草植株对 Zn 和 Cd 的耐受性和积累能力。结果表明，与野生型烟草相比，烟草中高水平表达 可显著增强地上部分和根部对 Zn 和 Cd 的积累，同时赋予转基因烟草对 Zn 和 Cd 的更大耐受性。亚细胞定位表明 定位于烟草的细胞核和细胞质。我们的研究表明， 可用于植物修复土壤以去除重金属。
