Pyrophosphate Stimulates the Phosphate-Sodium Symporter of Trypanosoma brucei Acidocalcisomes and Saccharomyces cerevisiae Vacuoles.

ABSTRACT: Inorganic pyrophosphate (PPi) is a by-product of biosynthetic reactions and has bioenergetic and regulatory roles in a variety of cells. Here we show that PPi and other pyrophosphate-containing compounds, including polyphosphate (polyP), can stimulate sodium-dependent depolarization of the membrane potential and Pi conductance in Xenopus oocytes expressing a Saccharomyces cerevisiae or Trypanosoma brucei Na+/Pi symporter. PPi is not taken up by Xenopus oocytes, and deletion of the TbPho91 SPX domain abolished its depolarizing effect. PPi generated outward currents in Na+/Pi-loaded giant vacuoles prepared from wild-type or pho91Δ yeast strains expressing TbPHO91 but not from the pho91Δ strains. Our results suggest that PPi, at physiological concentrations, can function as a signaling molecu

SUBMITTER: Potapenko E 

PROVIDER: S-EPMC6449605 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature