State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, China.
School of Environmental Science and Engineering, Guangdong Provincial Key Lab for Environmental Pollution Control and Remediation Technology,Sun Yat-sen University, Guangzhou, China.
J Exp Bot. 2020 Aug 6;71(16):4828-4842. doi: 10.1093/jxb/eraa211.
Members of the Low Phosphate Root (LPR) family have been identified in rice (Oryza sativa) and expression analyses have been conducted. Here, we investigated the functions of one of the five members in rice, LPR5. qRT-PCR and promoter-GUS reporter analyses indicated that under Pi-sufficient conditions OsLPR5 was highly expressed in the roots, and specific expression occurred in the leaf collars and nodes, and its expression was increased under Pi-deficient conditions. In vitro analysis of the purified OsLPR5 protein showed that it exhibited ferroxidase activity. Overexpression of OsLPR5 triggered higher ferroxidase activity, and elevated concentrations of Fe(III) in the xylem sap and of total Fe in the roots and shoots. Transient expression of OsLPR5 in Nicotiana benthamiana provided evidence of its subcellular localization to the cell wall and endoplasmic reticulum. Knockout mutation in OsLPR5 by means of CRISPR-Cas9 resulted in adverse effects on Pi translocation, on the relative expression of Cis-NATOsPHO1;2, and on several morphological traits, including root development and yield potential. Our results indicate that ferroxidase-dependent OsLPR5 has both a broad-spectrum influence on growth and development in rice as well as affecting a subset of physiological and molecular traits that govern Pi homeostasis.
在水稻（Oryza sativa）中已经鉴定出低磷酸盐根（LPR）家族的成员，并进行了表达分析。在这里，我们研究了水稻中五个成员之一的 LPR5 的功能。qRT-PCR 和启动子-GUS 报告分析表明，在磷充足条件下，OsLPR5 在根中高度表达，在叶鞘和节点中特异性表达，在磷缺乏条件下其表达增加。对纯化的 OsLPR5 蛋白的体外分析表明，它具有铁氧化酶活性。OsLPR5 的过表达触发了更高的铁氧化酶活性，导致木质部汁液中的 Fe(III)浓度和根和地上部分的总铁浓度升高。在 Nicotiana benthamiana 中的 OsLPR5 的瞬时表达提供了其定位于细胞壁和内质网的亚细胞定位的证据。通过 CRISPR-Cas9 对 OsLPR5 的敲除突变导致磷转运、 Cis-NATOsPHO1;2 的相对表达以及包括根系发育和产量潜力在内的几种形态特征受到不利影响。我们的结果表明，铁氧化酶依赖的 OsLPR5 对水稻的生长和发育具有广谱影响，并影响一组调节磷稳态的生理和分子特征。
