High-affinity H(+)/sulfate cotransporter that mediates the uptake of the environmental sulfate by plant roots under low-sulfur conditions. Plays a central role in the regulation of sulfate assimilation. Interacts with OASA1 through its STAS domain. Expressed in lateral root cap, root hairs, epidermal and cortical cells of roots. In roots by sulfate starvation or after selenate treatment. Belongs to the SLC26A/SulP transporter (TC 2.A.53) family.