The auxin-inducible phosphate transporter AsPT5 mediates phosphate transport and is indispensable for arbuscule formation in Chinese milk vetch at moderately high phosphate supply
The auxin-inducible phosphate transporter AsPT5 mediates phosphate transport and is indispensable for arbuscule formation in Chinese milk vetch at moderately high phosphate supply
复制标题
生长素诱导的磷酸盐转运蛋白 AsPT5 介导磷酸盐转运，对于中等高磷酸盐供应下紫云英的丛枝形成是不可或缺的
DOI：
10.1111/1462-2920.14952
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发表时间：
2020-06-01
影响因子：
5.1
通讯作者：
Xie, Xianan
中科院分区：
文献类型：
--
作者：
Fan, Xiaoning;Che, Xianrong;Xie, Xianan
磷是植物生存所必需的大量营养物质。大多数陆地植物已经进化出与丛枝菌根（AM）真菌形成互惠共生的能力，这增强了磷酸盐（Pi）的获取。调节π转运体系统是菌根植物适应环境π浓度的主要策略。然而，磷酸盐转运蛋白1 （PHT1）基因的具体功能在很大程度上是未知的，PHT1基因是对高Pi可用性有反应的Pi转运蛋白。在这里，我们报道了AsPT5是黄芪PHT1基因家族的成员，在双子叶中保守，并在广泛的组织中独立表达，不依赖于Pi的供应，但在中等高Pi条件下，吲哚-3-乙酸（生长素）处理显著诱导。亚细胞定位实验表明，AsPT5定位于植物细胞的质膜上。通过反向遗传学研究，我们发现AsPT5不仅介导π的转运和重塑根系结构，而且在中等高浓度的π条件下对紫杉树丛枝的形成至关重要。总的来说，我们的研究揭示了AsPT5在菌根植物Pi转运、AM发育以及Pi营养与生长素信号传导之间的串扰中的功能。
Phosphorus is a macronutrient that is essential for plant survival. Most land plants have evolved the ability to form a mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, which enhances phosphate (Pi) acquisition. Modulation of Pi transporter systems is the master strategy used by mycorrhizal plants to adapt to ambient Pi concentrations. However, the specific functions of PHOSPHATE TRANSPORTER 1 (PHT1) genes, which are Pi transporters that are responsive to high Pi availability, are largely unknown. Here, we report that AsPT5, an Astragalus sinicus (Chinese milk vetch) member of the PHT1 gene family, is conserved across dicotyledons and is constitutively expressed in a broad range of tissues independently of Pi supply, but is remarkably induced by indole-3-acetic acid (auxin) treatment under moderately high Pi conditions. Subcellular localization experiments indicated that AsPT5 localizes to the plasma membrane of plant cells. Using reverse genetics, we showed that AsPT5 not only mediates Pi transport and remodels root system architecture but is also essential for arbuscule formation in A. sinicus under moderately high Pi concentrations. Overall, our study provides insight into the function of AsPT5 in Pi transport, AM development and the cross-talk between Pi nutrition and auxin signalling in mycorrhizal plants.