Guangdong Provincial Key Lab for Environmental Pollution Control and Remediation Technology, Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil Remediation, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China.
Environ Sci Technol. 2022 Oct 4;56(19):14178-14187. doi: 10.1021/acs.est.2c04367. Epub 2022 Sep 13.
Arsenic (As) is toxic and ubiquitous in the environment, posing a growing threat to human health. As-hyperaccumulator has been used for phytoremediation of As-contaminated soil. Symbiosis with arbuscular mycorrhizal fungi (AMF) enhances As accumulation by , which is different from As inhibition in typical plants. In this study, seedlings inoculated with or without AMF were cultivated in As-contaminated soils for 2 months. AMF-root symbiosis enhanced plant growth, with 64.5% greater As contents in the fronds. After exposure to AsV for 2 h, the arsenate (AsV) and arsenite (AsIII) contents in AMF-roots increased by 1.8- and 3.6-fold, suggesting more efficient As uptake by with AMF-roots. Plants take up and transport AsV via phosphate transporters (Phts). Here, for the first time, we identified a novel mycorrhiza-specific Pht transporter, PvPht1;6, from . The transcripts of were strongly induced in AMF-roots, which were localized to the plasma membrane of arbuscule-containing cells. By complementing a yeast mutant lacking 5-Phts, we confirmed PvPht1;6's transport activity for both P and AsV. In contrast to typical AMF-inducible phosphate transporter LePT4 from tomato, PvPht1;6 showed greater AsV transport capacity. The results suggest that PvPht1;6 is probably critical for AsV transport at the periarbuscular membrane of root cells, revealing the underlying mechanism of efficient As accumulation in with AMF-roots.
砷（As）在环境中具有毒性和普遍性，对人类健康构成了日益严重的威胁。砷超积累植物已被用于修复砷污染土壤。与丛枝菌根真菌（AMF）共生会增强砷的积累，这与典型植物中的砷抑制作用不同。在这项研究中，将接种或不接种 AMF 的 幼苗在砷污染的土壤中培养 2 个月。AMF-根共生促进了植物的生长，叶片中的砷含量增加了 64.5%。暴露于砷 V（AsV） 2 小时后，AMF-根中的砷酸盐（AsV）和亚砷酸盐（AsIII）含量分别增加了 1.8 倍和 3.6 倍，表明 AMF-根中 对砷的吸收效率更高。植物通过磷酸盐转运蛋白（Phts）摄取和转运 AsV。在这里，我们首次从 中鉴定出一种新型的菌根特异 Pht 转运蛋白 PvPht1;6。 的转录物在 AMF-根中强烈诱导，定位于含有丛枝的细胞的质膜上。通过互补缺乏 5-Phts 的酵母突变体，我们证实了 PvPht1;6 对 P 和 AsV 的转运活性。与番茄中典型的 AMF 诱导型磷酸盐转运蛋白 LePT4 不同，PvPht1;6 对 AsV 的转运能力更强。结果表明，PvPht1;6 可能对 根细胞周丛膜上的 AsV 转运至关重要，揭示了 AMF-根中 高效积累砷的潜在机制。
