title: OsPHF1 regulates the plasma membrane localization of low- and high-affinity inorganic phosphate transporters and determines inorganic phosphate uptake and translocation in rice.
abstract: PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR1 (PHF1) is known to regulate the plasma membrane localization of PHT1;1, a high-affinity inorganic phosphate (Pi) transporter in Arabidopsis (Arabidopsis thaliana). OsPHF1, a rice (Oryza sativa) gene homologous to AtPHF1, was isolated and found to regulate the localization of both low- and high-affinity Pi transporters to the plasma membrane. Three OsPHF1 allelic mutants carrying one-point mutations at the fifth WD-repeat motif and two at the transmembrane helix, respectively, showed arsenate resistance and severely reduced Pi accumulation. The data indicate that mutation of OsPHF1 results in the endoplasmic reticulum retention of the low-affinity Pi transporter OsPT2 and high-affinity Pi transporter OsPT8. Mutation of OsPHF1 also reduced Pi accumulation in plants exhibiting excessive shoot Pi accumulation due to the overexpression of OsPHR2. However, the transcript level of OsPHF1 itself is not controlled by OsPHR2. Overexpression of OsPHF1 increased Pi accumulation in both roots and shoots in a solution culture with Pi-supplied condition. These results indicate that the role of OsPHF1 is unique in the localization of both low- and high-affinity Pi transporters on the plasma membrane in rice and determines Pi uptake and translocation in rice. The similar function of PHF1 required to facilitate PHT1 transit through the endoplasmic reticulum between Arabidopsis and rice provides an example of expectations from what one would deduce from sequence comparisons to extend knowledge from Arabidopsis to crops.
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou 310058, People's Republic of China.
authors.forename: Jieyu
authors.initials: J
authors.lastname: Chen
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Ni
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Youhuang
authors.initials: Y
authors.lastname: Bai
authors.forename: Jing
authors.initials: J
authors.lastname: Shi
authors.forename: Jian
authors.initials: J
authors.lastname: Gan
authors.forename: Zhongchang
authors.initials: Z
authors.lastname: Wu
authors.forename: Ping
authors.initials: P
authors.lastname: Wu
mesh_terms: D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D017343:Genes, Plant; D017136:Ion Transport; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D028061:Phosphate Transport Proteins / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010940:Plant Proteins / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D028061:Phosphate Transport Proteins; D010710:Phosphates; D010940:Plant Proteins