title: Fine characterization of OsPHO2 knockout mutants reveals its key role in Pi utilization in rice.
abstract: Previous research using forward genetics approaches demonstrated that OsPHO2 regulates multiple phosphate-starvation responses in rice. In this work, we finely characterized two independent OsPHO2 knockout rice mutants under inorganic phosphate (Pi)-sufficient conditions. The ospho2 mutants exhibited defects in growth and reproductive development in the whole growing period. The cells in the elongation zone of ospho2 seedling roots were much shorter than those of the wild type. The phosphorus concentration in the blades of ospho2 mutants was 5.8-fold higher than those of wild-type plants, whereas it was only slightly higher in the sheaths, culms, spikelets, and seeds. Furthermore, Pi levels in the ospho2 mutants were highest in the oldest leaf and lowest in the youngest leaf, whereas there was no significant difference in the corresponding leaves of wild-type plants. These results suggest that ospho2 mutant phenotype results from a partial defect in Pi translocation and remobilization in the shoot of rice. This study thus provides evidence that OsPHO2, which functions at the downstream of OsPHF1, modulates Pi utilization by regulating the expression of Pht1 transporters in rice.
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Cao
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Hua-dun
authors.initials: HD
authors.lastname: Wang
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Mian
authors.initials: M
authors.lastname: Gu
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Xue-neng
authors.initials: XN
authors.lastname: Wu
authors.affiliation: 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, Nanjing 210095, China. Electronic address: sunshubin@njau.edu.cn.
authors.forename: Shu-bin
authors.initials: SB
authors.lastname: Sun
authors.affiliation: 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, Nanjing 210095, China.
authors.forename: Guo-hua
authors.initials: GH
authors.lastname: Xu
mesh_terms: D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D012275:Oryza / Q000378:metabolism*; D010710:Phosphates; D010940:Plant Proteins / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000378:metabolism
chemical_list: D010710:Phosphates; D010940:Plant Proteins
keywords: Mutation; OsPHO2; Phosphate; Rice; Utilization