Inorganic phosphate uptake in unicellular eukaryotes

• Pi uptake is the major point in Pi homeostasis.
• PiT family represents the Na+:Pi cotransporters, based in S. cerevisiae Pho89p.
• PHS family represents the H+:Pi cotransporters, based in S. cerevisiae Pho84p.
• PHS transporter could act as Pi sensor and downstream pathways.

BackgroundInorganic phosphate (Pi) is an essential nutrient for all organisms. The route of Pi utilization begins with Pi transport across the plasma membrane.Scope of reviewHere, we analyzed the gene sequences and compared the biochemical profiles, including kinetic and modulator parameters, of Pi transporters in unicellular eukaryotes. The objective of this review is to evaluate the recent findings regarding Pi uptake mechanisms in microorganisms, such as the fungi Neurospora crassa and Saccharomyces cerevisiae and the parasite protozoans Trypanosoma cruzi, Trypanosoma rangeli, Leishmania infantum and Plasmodium falciparum.Major conclusionPi uptake is the key step of Pi homeostasis and in the subsequent signaling event in eukaryotic microorganisms.General significanceBiochemical and structural studies are important for clarifying mechanisms of Pi homeostasis, as well as Pi sensor and downstream pathways, and raise possibilities for future studies in this field.