The Phosphate Transporter Gene OsPht1;8 Is Involved in Phosphate Homeostasis in Rice
The Phosphate Transporter Gene OsPht1;8 Is Involved in Phosphate Homeostasis in Rice
复制标题
磷酸盐转运蛋白基因 OsPht1;8 参与水稻磷酸盐稳态
DOI：
10.1104/pp.111.175240
复制
发表时间：
2011-07-01
期刊：
影响因子：
7.4
通讯作者：
Xu, Guohua
中科院分区：
文献类型：
--
作者：
Jia, Hongfang;Ren, Hongyan;Xu, Guohua
植物磷酸盐转运体（PTs）在从土壤吸收无机磷酸盐（Pi）及其在植物内的转运中很活跃。本文就OsPht1的生物学特性和生理作用作一综述；8 （OsPT8）是水稻（Oryza sativa）中属于Pht1家族的PTs之一。由OsPT8启动子驱动的β -葡萄糖醛酸酶和绿色荧光蛋白报告基因的表达表明，OsPT8在从根到种子的各个组织器官中均有表达，不依赖于Pi的供应。OsPT8能够补充酵母Pi摄取突变体，并在外源溶液中添加微摩尔（33）Pi浓度时增加非洲爪蟾卵母细胞的Pi积累，表明它对Pi运输具有高亲和力。OsPT8过表达导致根和芽中π超标，在高π供应条件下出现π中毒症状。相比之下，在高和低Pi条件下，通过RNA干扰敲低OsPT8会降低植物对Pi的吸收和生长。此外，抑制OsPT8导致穗轴磷含量增加，未灌浆谷壳磷含量降低，结实率降低。综上所述，我们的数据表明OsPT8参与水稻Pi稳态，对植物生长发育至关重要。
Plant phosphate transporters (PTs) are active in the uptake of inorganic phosphate (Pi) from the soil and its translocation within the plant. Here, we report on the biological properties and physiological roles of OsPht1;8 (OsPT8), one of the PTs belonging to the Pht1 family in rice (Oryza sativa). Expression of a beta-glucuronidase and green fluorescent protein reporter gene driven by the OsPT8 promoter showed that OsPT8 is expressed in various tissue organs from roots to seeds independent of Pi supply. OsPT8 was able to complement a yeast Pi-uptake mutant and increase Pi accumulation of Xenopus laevis oocytes when supplied with micromolar (33)Pi concentrations at their external solution, indicating that it has a high affinity for Pi transport. Overexpression of OsPT8 resulted in excessive Pi in both roots and shoots and Pi toxic symptoms under the high-Pi supply condition. In contrast, knockdown of OsPT8 by RNA interference decreased Pi uptake and plant growth under both high- and low-Pi conditions. Moreover, OsPT8 suppression resulted in an increase of phosphorus content in the panicle axis and in a decrease of phosphorus content in unfilled grain hulls, accompanied by lower seed-setting rate. Altogether, our data suggest that OsPT8 is involved in Pi homeostasis in rice and is critical for plant growth and development.