MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China.
MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China.
Ecotoxicol Environ Saf. 2018 Jul 30;156:279-286. doi: 10.1016/j.ecoenv.2018.03.031. Epub 2018 Mar 20.
SaNRAMP3 gene cloned from a Zn/Cd hyperaccumulator Sedum alfredii was ectopicly expressed in Brassica juncea, a fast-growing and high-biomass crop plant. In a tissue culture experiment, transgenic plants were grown on MS medium with 0, 25, 50, 100, 200 μM Cd. It was shown that, at the same Cd treatment, the Cd tolerance of transgenic plants had no significant difference with those of wild-type plants (WT). However, the shoot Cd content and accumulation were improved significantly while the root Cd content and accumulation were descended significantly by SaNRAMP3 gene expression, which obviously enhanced the Cd root-to-shoot translocation factor (TF). In the hydroponic experiment, plants were cultured in nutrition solution with 0, 2.5, 25 μM Cd. Data showed that the Cd tolerance of transgenic plants had no significant difference with that of WT under the same Cd exposure. Whereas, the shoot Cd content and accumulation was increased 1.43-1.81 times and the TF was enhanced 3.09-3.51 times by SaNRAMP3 gene expression. Those results indicated that ectopic expression of SaNRAMP3 in B. juncea didn't lead to Cd sensitivity, but enhanced Cd root-to-shoot transport, so that increased shoot Cd accumulation. This study provided a possibility to improve phytoextraction efficiency of heavy metal through gene engineering.
从 Zn/Cd 超积累植物景天属中克隆的 SaNRAMP3 基因在生长迅速、生物量高的作物油菜中异位表达。在组织培养实验中，将转基因植物在含有 0、25、50、100、200 μM Cd 的 MS 培养基上生长。结果表明，在相同 Cd 处理下，转基因植物的 Cd 耐性与野生型植物（WT）没有显著差异。然而，SaNRAMP3 基因的表达显著提高了转基因植物的地上部 Cd 含量和积累，同时降低了根 Cd 含量和积累，明显提高了 Cd 根到地上部的转运因子（TF）。在水培实验中，植物在含有 0、2.5、25 μM Cd 的营养液中培养。结果表明，在相同 Cd 暴露下，转基因植物的 Cd 耐性与 WT 没有显著差异。然而，SaNRAMP3 基因的表达使转基因植物的地上部 Cd 含量和积累增加了 1.43-1.81 倍，TF 增强了 3.09-3.51 倍。这些结果表明，SaNRAMP3 在油菜中的异位表达并没有导致 Cd 敏感性，但增强了 Cd 从根部到地上部的运输，从而增加了地上部的 Cd 积累。本研究为通过基因工程提高重金属植物提取效率提供了可能。
