Becquer Adeline, Garcia Kevin, Plassard Claude
a Eco&Sols , University Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro , Montpellier , France .
b Department of Crop and Soil Sciences , North Carolina State University , Raleigh , NC , USA .
Plant Signal Behav. 2018;13(10):e1525997. doi: 10.1080/15592324.2018.1525997. Epub 2018 Oct 5.
Ectomycorrhizal fungi improve tree phosphorus nutrition through transporters specifically localized at soil-hyphae and symbiotic interfaces. In the model symbiosis between the fungus Hebeloma cylindrosporum and the maritime pine (Pinus pinaster), several transporters possibly involved in phosphate fluxes were identified, including three H:Pi transporters. Among these three, we recently unraveled the function of one of them, named HcPT2, in both pure culture and symbiotic interaction with P. pinaster. Here we investigated the transporter named HcPT1.2, by analyzing inorganic phosphate transport ability in a yeast complementation assay, assessing its expression in the fungus associated or not with the plant, and immunolocalizing the proteins in ectomycorrhizas. We also evaluated the effect of external Pi concentration on expression and localization of HcPT1.2. Our results revealed that HcPT1.2 is involved in Pi acquisition by H. cylindrosporum mycelium, irrespective of the external Pi concentrations.
外生菌根真菌通过特异性定位于土壤-菌丝和共生界面的转运蛋白来改善树木的磷营养状况。在真菌圆柱齿杯伞（Hebeloma cylindrosporum）与海岸松（Pinus pinaster）的模式共生关系中，鉴定出了几种可能参与磷酸盐通量的转运蛋白，其中包括三种H⁺/Pi转运蛋白。在这三种转运蛋白中，我们最近揭示了其中一种名为HcPT2的转运蛋白在纯培养以及与海岸松的共生相互作用中的功能。在此，我们通过酵母互补试验分析无机磷酸盐转运能力、评估其在与植物相关或不相关的真菌中的表达情况以及对外生菌根中的蛋白质进行免疫定位，对名为HcPT1.2的转运蛋白展开了研究。我们还评估了外部Pi浓度对HcPT1.2表达和定位的影响。我们的结果表明，无论外部Pi浓度如何，HcPT1.2都参与了圆柱齿杯伞菌丝体对Pi的获取。
