NMT歷史上的今天
2017年10月17日，中國林科院亞熱帶林業(yè)研究所卓仁英、陳雙雙利用NMT在Scientific Reports上發(fā)表了標(biāo)題為Sedum alfredii SaNramp6 Metal Transporter Contributes to Cadmium Accumulation in Transgenic Arabidopsis thaliana的研究成果。
期刊：Scientific Reports
主題：東南景天金屬轉(zhuǎn)運蛋白有助于轉(zhuǎn)基因擬南芥中鎘的積累
標(biāo)題：Sedum alfredii SaNramp6 Metal Transporter Contributes to Cadmium Accumulation in Transgenic Arabidopsis thaliana
影響因子：4.259
檢測指標(biāo)：Cd2+流速
檢測部位：擬南芥根部（距離根尖120μm）
Cd2+流實驗處理方法：
30日齡的擬南芥幼苗，在0/50μM CdCl2中處理24 h
Cd2+流實驗測試液成份：
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：中國林科院亞熱帶林業(yè)研究所卓仁英、陳雙雙
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（谷歌機翻）
植物天然抗性相關(guān)的巨噬細胞蛋白（Nramp）家族在重金屬脅迫耐受性中起重要作用。然而，在重金屬富集植物景天草中，很少有Nramps在功能上有特征。
在此，從苜蓿鏈球菌克隆并鑒定了Nramp6，并在轉(zhuǎn)基因擬南芥中分析了其功能。 SaNramp6 cDNA包含一個1，638 bp的開放閱讀框，編碼545個氨基酸。
SaNramp6的表達可以通過鎘（Cd）脅迫誘導(dǎo)，處理后，其在根和葉中分別在1周和12μh達到峰值。 SaNramp6定位于原生質(zhì)體中的質(zhì)膜，該原生質(zhì)體是從擬南芥，本氏煙草下部葉片和洋蔥（洋蔥）表皮細胞中分離出來的。 SaNramp6在Δycf1酵母突變體中的異源表達增加了酵母細胞中Cd的含量。
SaNramp6還挽救了擬南芥nramp1突變體的低Cd積累。表達SaNramp6的轉(zhuǎn)基因擬南芥表現(xiàn)出高Cd積累水平，這是通過對Cd脅迫下Cd濃度，易位因子和Cd2 +凈通量的統(tǒng)計分析確定的。
因此，SaNramp6可能在改善Cd積累中起重要作用，該基因可能對轉(zhuǎn)基因植物進行植物修復(fù)的生物技術(shù)開發(fā)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.