Sun Dan, Zhang Wen, Feng Huayuan, Li Xinyuan, Han Ran, Turner Benjamin L, Qiu Rongliang, Cao Yue, Ma Lena Q
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China.
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China; State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China.
J Hazard Mater. 2022 Feb 5;423(Pt B):127106. doi: 10.1016/j.jhazmat.2021.127106. Epub 2021 Sep 6.
Developing P-efficient plants helps improve P uptake from soils with low-available P and reduce environmental damage by P runoff. Here, we investigated a novel root-specific phytase PvPHY1 from As-hyperaccumulator Pteris vittata, which can efficiently utilize phytate, a recalcitrant organic phosphorus in soil. Unlike other plants, expression of PvPHY1 in P. vittata was greater in the roots than the fronds. A pure phytase with considerable activity was obtained via prokaryotic expression. Expressing PvPHY1 in tobacco (PvPHY1-Ex) enhanced its growth (2.8 to 3.5-3.9 g per plant) and increased its P accumulation by 10-50% under low- and adequate-P conditions. Further, PvPHY1-Ex tobacco showed 25-32% lower intracellular phytate and 30-56% higher inorganic P in the roots, likely due to phytase-mediated hydrolysis of phytate. Decrease of phytate levels up-regulated phosphate transporter genes (NbPht1;1, NbPht1;2 and NbPht1;6), leading to greater P and As uptake. However, As translocation to the shoots was low, probably due to competition from increased inorganic P via phytate hydrolysis. As such, PvPHY1 facilitated P uptake from soils and phytate hydrolysis in plants, thereby promoting tobacco growth. Overall, PvPHY1 from P. vittata helps better understand the novel phytase to increase soil P utilization efficiency, thereby reducing P fertilizer requirements for crop production.
培育磷高效植物有助于提高从有效磷含量低的土壤中吸收磷的能力，并减少磷径流对环境的破坏。在此，我们研究了一种来自砷超富集植物蜈蚣草的新型根系特异性植酸酶PvPHY1，它能够有效利用植酸盐，这是土壤中一种难降解的有机磷。与其他植物不同，PvPHY1在蜈蚣草根部的表达高于叶部。通过原核表达获得了具有相当活性的纯植酸酶。在烟草中表达PvPHY1（PvPHY1-Ex）可促进其生长（每株植物2.8至3.5 - 3.9克），并在低磷和适磷条件下使其磷积累增加10% - 50%。此外，PvPHY1-Ex烟草根部的细胞内植酸盐含量降低了25% - 32%，无机磷含量提高了30% - 56%，这可能是由于植酸酶介导的植酸盐水解所致。植酸盐水平的降低上调了磷酸盐转运蛋白基因（NbPht1;1、NbPht1;2和NbPht1;6），导致更多的磷和砷吸收。然而，砷向地上部的转运较低，这可能是由于植酸盐水解增加的无机磷产生的竞争作用。因此，PvPHY1促进了植物从土壤中吸收磷以及植物体内的植酸盐水解，从而促进了烟草生长。总体而言，蜈蚣草中的PvPHY1有助于更好地理解这种新型植酸酶，以提高土壤磷利用效率，从而减少作物生产对磷肥的需求。
