title: A putative high affinity phosphate transporter, CmPT1, enhances tolerance to Pi deficiency of chrysanthemum.
abstract: BACKGROUND
  Inorganic phosphate (Pi) is essential for plant growth, and phosphorus deficiency is a main limiting factor in plant development. Its acquisition is largely mediated by Pht1 transporters, a family of plasma membrane-located proteins. Chrysanthemum is one of the most important ornamental plants, its productivity is usually compromised when grown in phosphate deficient soils, but the study of phosphate transporters in chrysanthemum is limited.
  
  
  RESULTS
  We described the isolation from chrysanthemum of a homolog of the Phosphate Transporter 1 (PT1) family. Its predicted product is a protein with 12 transmembrane domains, highly homologous with other high affinity plant Pi transporters. Real-time quantitative PCR analysis revealed that the gene was transcribed strongly in the root, weakly in the stem and below the level of detection in the leaf of chrysanthemum plants growing in either sufficient or deficient Pi conditions. Transcript abundance was greatly enhanced in Pi-starved roots. A complementation assay in yeast showed that CmPT1 partially compensated for the absence of phosphate transporter activity in yeast strain MB192. The estimated Km of CmPT1 was 35.2 μM. Under both Pi sufficient and deficient conditions, transgenic plants constitutively expressing CmPT1 grew taller than the non-transformed wild type, produced a greater volume of roots, accumulated more biomass and took up more phosphate.
  
  
  CONCLUSIONS
  CmPT1 encodes a typical, root-expressed, high affinity phosphate transporter, plays an important role in coping Pi deficiency of chrysanthemum plants.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.forename: Sumei
authors.initials: S
authors.lastname: Chen
authors.forename: Aiping
authors.initials: A
authors.lastname: Song
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhao
authors.forename: Weimin
authors.initials: W
authors.lastname: Fang
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Guan
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liao
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. jiangjiafu@njau.edu.cn.
authors.forename: Jiafu
authors.initials: J
authors.lastname: Jiang
authors.forename: Fadi
authors.initials: F
authors.lastname: Chen
mesh_terms: D031202:Chrysanthemum / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D028061:Phosphate Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010710:Phosphates / Q000172:deficiency / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D028061:Phosphate Transport Proteins; D010710:Phosphates; D010940:Plant Proteins