5-Diphosphoinositol pentakisphosphate (5-IP₇) regulates phosphate release from acidocalcisomes and yeast vacuoles.

ABSTRACT: Acidocalcisomes of Trypanosoma brucei and the acidocalcisome-like vacuoles of Saccharomyces cerevisiae are acidic calcium compartments that store polyphosphate (polyP). Both organelles possess a phosphate-sodium symporter (TbPho91 and Pho91p in T. brucei and yeast, respectively), but the roles of these transporters in growth and orthophosphate (P_i) transport are unclear. We found here that Tbpho91 ^-/- trypanosomes have a lower growth rate under phosphate starvation and contain larger acidocalcisomes that have increased P_i content. Heterologous expression of TbPHO91 in Xenopus oocytes followed by two-electrode voltage clamp recordings disclosed that myo-inositol polyphosphates stimulate both sodium-dependent d

SUBMITTER: Potapenko E 

PROVIDER: S-EPMC6295732 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature