State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Silviculture of the National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.
Forest, Range and Watershed Management Department, Agriculture and Natural Resources Faculty, Yasouj University, Yasuj 75919-63179, Iran.
Int J Mol Sci. 2022 Jul 8;23(14):7593. doi: 10.3390/ijms23147593.
Poplars are proposed for the phytoremediation of heavy metal (HM) polluted soil. Characterization of genes involved in HM uptake and accumulation in poplars is crucial for improving the phytoremediation efficiency. Here, 1 () encoding a transporter involved in cadmium (Cd) uptake and transport was functionally characterized in × . Eight putative were identified in the poplar genome and most of them were primarily expressed in the roots. The expression of was induced in Cd-exposed roots and it encoded a plasma membrane-localized protein. PcNRAMP1 showed transport activity for Cd when expressed in yeast. The -overexpressed poplars enhanced net Cd influxes by 39-52% in the roots and Cd accumulation by 25-29% in aerial parts compared to the wildtype (WT). However, Cd-induced biomass decreases were similar between the transgenics and WT. Further analysis displayed that the two amino acid residues of PcNRAMP1, i.e., M236 and P405, play pivotal roles in regulating its transport activity for Cd. These results suggest that PcNRAMP1 is a plasma membrane-localized transporter involved in Cd uptake and transporting Cd from the roots to aerial tissues, and that the conserved residues in PcNRAMP1 are essential for its Cd transport activity in poplars.
杨树被提议用于修复重金属（HM）污染土壤。鉴定参与杨树 HM 吸收和积累的基因对于提高植物修复效率至关重要。在这里，功能表征了拟南芥中编码 Cd 摄取和转运的转运蛋白 1（）。在杨树种鉴定到 8 个推定的，它们主要在根部表达。在 Cd 暴露的根中诱导表达，它编码一种质膜定位的蛋白。PcNRAMP1 在酵母中表达时表现出对 Cd 的转运活性。与野生型（WT）相比，过表达的杨树增加了根中的 Cd 净流入 39-52%，地上部分的 Cd 积累增加了 25-29%。然而，Cd 诱导的生物量减少在转基因和 WT 之间相似。进一步的分析表明，PcNRAMP1 的两个氨基酸残基，即 M236 和 P405，在调节其 Cd 转运活性方面起着关键作用。这些结果表明，PcNRAMP1 是一种质膜定位的转运蛋白，参与 Cd 的摄取和从根部向地上组织的转运，并且 PcNRAMP1 中的保守残基对于其在杨树中的 Cd 转运活性是必需的。
