Key message

Twelve HbPHT1s were identified in Hevea and most of them were induced by phosphate starvation. HbPHT1;5 complemented the defective yeast mutant strain EY917 and HbPHT1;7 only partly complemented it.

Abstract

Phosphorus is an important element of the latex of rubber tree, and its content affects the quality and yield of latex. However, with the outflow of latex, a large amount of phosphorus is lost. The phosphate transporter 1 (PHT1) family proteins regulate the phosphorus acquisition and translocation in the plants, but their expression and roles in Hevea brasiliensis remain unclear. In this work, we identified twelve HbPHT1s (HbPHT1;1 to HbPHT1;12). Evolutionary analyses suggested two duplication events: HbPHT1;5/HbPHT1;6 and HbPHT1;7/HbPHT1;8. In the promoter region of some HbPHT1s, there existed P1BS, W-box, MYB, and ethylene response cis-elements. All the HbPHT1s, except for HbPHT1;4, were expressed in the roots, and most of them were also expressed in the stems and leaves. HbPHT1;7 had the highest expression level in the roots, stems, and leaves. HbPHT1;5 and HbPHT1;6 had a relatively higher expression levels than other genes in latex. HbPHT1;5, HbPHT1;7, and HbPHT1;11 were induced by ethylene treatment. Most HbPHT1s were induced under phosphate starvation conditions in the seedling leaves, and the expression of HbPHT1;9 was 20-fold higher than the control. HbPHT1;5 complemented the deficiency of the yeast mutant strain EY917 in phosphate transportation under low- and high-phosphate conditions, and HbPHT1;7 restored the deficiency when 10 mM phosphate was supplied. These results suggested that the increased expression of PHT1s may improve the phosphate uptake, transport, and utilization in Hevea. It also provides the basis to sudy the phosphorus metabolism network and mine the gene resources for the genetic breeding of Hevea.

中文翻译：

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巴西橡胶树磷酸转运蛋白1基因家族的鉴定与表达分析

关键信息

在橡胶树中鉴定出十二个HbPHT1，其中大多数是由磷酸盐饥饿诱导的。HbPHT1; 5补充了缺陷型酵母突变株EY917，而HbPHT1; 7仅部分补充了它。

抽象

磷是橡胶树胶乳的重要元素，其含量影响胶乳的质量和产量。但是，随着胶乳的流出，大量的磷损失了。磷酸盐转运蛋白1（PHT1）家族蛋白调节植物中磷的吸收和转运，但它们在巴西橡胶树中的表达和作用仍不清楚。在这项工作中，我们确定了十二个HbPHT1（HbPHT1; 1至HbPHT1; 12）。进化分析提示了两个重复事件：HbPHT1; 5 / HbPHT1; 6和HbPHT1; 7 / HbPHT1; 8。在某些HbPHT1s的启动子区域，存在P1BS，W-box，MYB和乙烯反应顺式元素。除HbPHT1; 4以外，所有HbPHT1s均在根部表达，其中大多数也在茎和叶中表达。HbPHT1; 7在根，茎和叶中的表达水平最高。HbPHT1; 5和HbPHT1; 6在乳胶中的表达水平高于其他基因。HbPHT1; 5，HbPHT1; 7和HbPHT1; 11通过乙烯处理诱导。多数HbPHT1s是在磷酸盐饥饿条件下诱导幼苗叶片中的，并且HbPHT1; 9的表达比对照高20倍 在低磷酸盐和高磷酸盐条件下，HbPHT1; 5补充了酵母突变菌株EY917在磷酸盐运输中的缺陷，当提供10 mM磷酸盐时，HbPHT1; 7恢复了该缺陷。这些结果表明，PHT1s表达的增加可能会改善橡胶树中磷酸盐的吸收，转运和利用。这也为研究磷代谢网络和挖掘橡胶树遗传育种的基因资源提供了基础。