《植物生理学报》 2013, 49(3): 253-258

转柽柳和星星草双价金属硫蛋白基因烟草对Cd²⁺和Cu²⁺的抗性分析

张艳^1,2,3,*, 杨传平⁴

1黑龙江省教育学院, 哈尔滨150080; 2东北林业大学博士后流动站, 哈尔滨150040; 3黑龙江省农业科学院博士后工作站, 哈

通信作者：张；E-mail: zy021208@163.com；Tel: 0451-82456373

摘　要：

金属硫蛋白(MT)是一类广泛存在于生物中的低分子量、富含半胱氨酸且可结合重金属的蛋白质, 在土壤重金属污染的治理中发挥重要作用。将从柽柳和星星草cDNA文库中克隆的MT基因构建在同一植物表达载体pRCXM上, 通过农杆菌介导的叶盘法转化烟草‘龙江911’, 获得了抗卡那霉素的转基因植株。PCR-Southern和Northern blot检测证明双价MT基因已整合进烟草基因组中并可正常表达。抗性试验证明双价MT基因的转入提高了转基因烟草对Cd2+和Cu2+的抗性, 转基因烟草分别能在300 μmol·L-1 Cd2+或150 μmol·L-1 Cu2+的胁迫下正常生长。本研究结果对通过基因工程技术培育植物修复新品种提供了理论基础。

关键词：金属硫蛋白; 星星草; 柽柳; 烟草

收稿：2012-12-14   修定：2013-01-28

资助：国家“973”计划项目(G1999016000)。

Ectopic Expression of Two Metallothionein Genes Enhances Tolerance to Cd²⁺ and Cu²⁺ in Tobacco (Nicotiana tabacum L.)

ZHANG Yan^1,2,3,*, YANG Chuan-Ping⁴

¹Heilongjiang College of Education, Harbin 150080, China; ²Station of Postdoctor, Northeast Forestry University, Harbin 150040, China; ³Station of Postdoctor, Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China; ⁴Key Laboratory of Forest Tree Genetic Improvement and Biotechnology, Ministry of Education, Northeast Forestry University, Harbin 150040, China

Corresponding author: ZHANG Yan; E-mail: zy021208@163.com; Tel: 0451-82456373

Abstract:

Metallothionein (MT) is a low molecular weight, cysteine-rich, and heavy metal-binding protein. MT plays important roles in controlling heavy metal pollution of soil. Two MT genes from Tamarix androssowii and Puccinellia tenuiflora were cloned into the same vector pRCXM. Kanamycin-resistant transgenic tobacco (Nico-tiana tabacum ‘Longjiang 911’) plants were obtained using Agrobacterium-mediated gene transferring method. PCR-Southern and Northern blot analysis indicated that two MT genes were indeed integrated into the tobacco genome and expressed in tobacco. Resistance tests proved that the expression of two MT genes enhanced toler-ance to Cd²⁺ and Cu²⁺ in tobacco. The transgenic plants can live in the medium with 300 µmol·L-1 Cd²⁺ or 150 µmol·L-1 Cu²⁺. Our study provides theoretical references for cultivating new varieties of phytoremediation by genetic engineering technology.

Key words: metallothionein; Puccinellia tenuiflora; Tamarix androssowii; tobacco (Nicotiana tabacum)