A phosphate transporter expressed in arbuscule-containing cells in potato

Nature. 2001 Nov 22;414(6862):462-70. doi: 10.1038/35106601.


Arbuscular mycorrhizas are the most common non-pathogenic symbioses in the roots of plants. It is generally assumed that this symbiosis facilitated the colonization of land by plants. In arbuscular mycorrhizas, fungal hyphae often extend between the root cells and tuft-like branched structures (arbuscules) form within the cell lumina that act as the functional interface for nutrient exchange. In the mutualistic arbuscular-mycorrhizal symbiosis the host plant derives mainly phosphorus from the fungus, which in turn benefits from plant-based glucose. The molecular basis of the establishment and functioning of the arbuscular-mycorrhizal symbiosis is largely not understood. Here we identify the phosphate transporter gene StPT3 in potato (Solanum tuberosum). Functionality of the encoded protein was confirmed by yeast complementation. RNA localization and reporter gene expression indicated expression of StPT3 in root sectors where mycorrhizal structures are formed. A sequence motif in the StPT3 promoter is similar to transposon-like elements, suggesting that the mutualistic symbiosis evolved by genetic rearrangements in the StPT3 promoter.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cloning, Molecular
  • Fungal Proteins / genetics
  • Fungi / genetics*
  • Genetic Complementation Test
  • Molecular Sequence Data
  • Phosphate Transport Proteins / classification
  • Phosphate Transport Proteins / genetics*
  • Phosphate Transport Proteins / metabolism
  • Phylogeny
  • Plant Proteins / classification
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plant Roots / microbiology
  • Promoter Regions, Genetic
  • RNA, Messenger / metabolism
  • RNA, Plant / metabolism
  • Solanum tuberosum / genetics*
  • Solanum tuberosum / microbiology
  • Symbiosis


  • Fungal Proteins
  • PT3 protein, Solanum tuberosum
  • Phosphate Transport Proteins
  • Plant Proteins
  • RNA, Messenger
  • RNA, Plant

Associated data

  • GENBANK/AJ318822