NMT历史上的今天
2017年10月17日，中国林科院亚热带林业研究所卓仁英、陈双双利用NMT在Scientific Reports上发表了标题为Sedum alfredii SaNramp6 Metal Transporter Contributes to Cadmium Accumulation in Transgenic Arabidopsis thaliana的研究成果。
期刊：Scientific Reports
主题：东南景天金属转运蛋白有助于转基因拟南芥中镉的积累
标题：Sedum alfredii SaNramp6 Metal Transporter Contributes to Cadmium Accumulation in Transgenic Arabidopsis thaliana
影响因子：4.259
检测指标：Cd2+流速
检测部位：拟南芥根部（距离根尖120μm）
Cd2+流实验处理方法：
30日龄的拟南芥幼苗，在0/50μM CdCl2中处理24 h
Cd2+流实验测试液成份：
0.05 mM CdCl2, 0.1 mM KCl, 0.02 mM CaCl2, 0.02 mM MgCl2, 0.5 mM NaCl, 0.1 mM Na2SO4 and 0.3 mM MES, pH 5.7
作者：中国林科院亚热带林业研究所卓仁英、陈双双
英文摘要
The plant natural resistance-associated macrophage protein (Nramp) family plays an important role in tolerance to heavy metal stress. However, few Nramps have been functionally characterized in the heavy metal-accumulating plant Sedum alfredii.
Here, Nramp6 was cloned and identified from S. alfredii and its function analyzed in transgenic Arabidopsis thaliana. SaNramp6 cDNA contains an open reading frame of 1, 638 bp encoding 545 amino acids.
SaNramp6′s expression can be induced by cadmium (Cd) stress, and, after treatment, it peaked at one week and 12 h in the roots and leaves, respectively. SaNramp6 localized to the plasma membrane in protoplasts isolated from A. thaliana, Nicotiana benthamiana lower leaf and onion (Allium cepa) epidermal cells. The heterologous expression of SaNramp6 in the Δycf1 yeast mutant increased the Cd content in yeast cells.
SaNramp6 also rescued the low Cd accumulation of the A. thaliana nramp1 mutant. Transgenic A. thaliana expressing SaNramp6 exhibited high Cd accumulation levels, as determined by a statistical analysis of the Cd concentration, translocation factors and net Cd2+ fluxes under Cd stress.
Thus, SaNramp6 may play a significant role in improving Cd accumulation, and the gene may be useful for the biotechnological development of transgenic plants for phytoremediation.
中文摘要（谷歌机翻）
植物天然抗性相关的巨噬细胞蛋白（Nramp）家族在重金属胁迫耐受性中起重要作用。然而，在重金属富集植物景天草中，很少有Nramps在功能上有特征。
在此，从苜蓿链球菌克隆并鉴定了Nramp6，并在转基因拟南芥中分析了其功能。 SaNramp6 cDNA包含一个1，638 bp的开放阅读框，编码545个氨基酸。
SaNramp6的表达可以通过镉（Cd）胁迫诱导，处理后，其在根和叶中分别在1周和12µh达到峰值。 SaNramp6定位于原生质体中的质膜，该原生质体是从拟南芥，本氏烟草下部叶片和洋葱（洋葱）表皮细胞中分离出来的。 SaNramp6在Δycf1酵母突变体中的异源表达增加了酵母细胞中Cd的含量。
SaNramp6还挽救了拟南芥nramp1突变体的低Cd积累。表达SaNramp6的转基因拟南芥表现出高Cd积累水平，这是通过对Cd胁迫下Cd浓度，易位因子和Cd2 +净通量的统计分析确定的。
因此，SaNramp6可能在改善Cd积累中起重要作用，该基因可能对转基因植物进行植物修复的生物技术开发有用。
Figure 8. Comparison of Cd concentrations and net Cd2+ -influx rates in four lines - WT (wild type); OE 2 and OE 3 (overexpression lines); Atnr (mutant line); Atnr-N24 and Atnr-N28 (rescue lines). (a,c) Cd2+ flux rateswith Cd treatment for 24 h. (b,d) Mean flow rates of Cd2+. Bars indicate means ± standard deviations (SDs) of at least three independent biological experiments. One or two asterisks indicate a significant difference at P < 0.05 or P < 0.01 from wild type.