State Key Lab of Pollution Control and Resource Reuse, School of the Environment , Nanjing University , Nanjing , Jiangsu 210023 , China.
State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture , Nanjing Agricultural University , Nanjing , Jiangsu 210095 , China.
Environ Sci Technol. 2018 Apr 3;52(7):3975-3981. doi: 10.1021/acs.est.7b06674. Epub 2018 Mar 22.
Phosphorus is an important macronutrient for plant growth and is acquired by plants mainly as phosphate (P). Phosphate transporters (Phts) are responsible for P and arsenate (AsV) uptake in plants including arsenic-hyperaccumulator Pteris vittata. P. vittata is efficient in AsV uptake and P utilization, but the molecular mechanism of its P uptake is largely unknown. In this study, a P. vittata Pht, PvPht1;2, was cloned and transformed into tobacco ( Nicotiana tabacum). In hydroponic experiments, all transgenic lines displayed markedly higher P content and better growth than wild type, suggesting that PvPht1;2 mediated P uptake in plants. In addition, expressing PvPht1;2 also increased the shoot/root P ratio by 69-92% and enhanced xylem sap P by 46-62%, indicating that PvPht1;2 also mediated P translocation in plants. Unlike many Phts permeable to AsV, PvPht1;2 showed little ability to transport AsV. In soil experiments, PvPht1;2 also significantly increased shoot biomass without elevating As accumulation in PvPht1;2 transgenic tobacco. Taken together, our results demonstrated that PvPht1;2 is a specific P transporter responsible for P acquisition and translocation in plants. We envisioned that PvPht1;2 can enhance crop P acquisition without impacting AsV uptake, thereby increasing crop production without compromising food safety.
磷是植物生长的重要大量营养素，主要通过磷酸盐（P）被植物吸收。磷酸盐转运蛋白（Phts）负责植物中的 P 和砷酸盐（AsV）的摄取，包括砷超积累植物凤尾蕨。凤尾蕨在 AsV 摄取和 P 利用方面效率很高，但 P 摄取的分子机制在很大程度上尚不清楚。在这项研究中，克隆并转化了凤尾蕨的一个 Pht，PvPht1;2 到烟草（Nicotiana tabacum）中。在水培实验中，所有转基因系的 P 含量明显高于野生型，生长状况明显好于野生型，表明 PvPht1;2 介导了植物中的 P 摄取。此外，表达 PvPht1;2 还使 shoot/root P 比增加了 69-92%，木质部汁液 P 增加了 46-62%，表明 PvPht1;2 还介导了植物中的 P 转运。与许多可通透 AsV 的 Phts 不同，PvPht1;2 对 AsV 的转运能力很小。在土壤实验中，PvPht1;2 也显著增加了 shoot 生物量，而没有提高 PvPht1;2 转基因烟草中的 As 积累。总之，我们的结果表明 PvPht1;2 是一种特异性 P 转运蛋白，负责植物中的 P 摄取和转运。我们设想 PvPht1;2 可以增强作物对 P 的获取，而不影响 AsV 的摄取，从而在不影响食品安全的情况下提高作物产量。
