Structural insights into a citrate transporter that mediates aluminum tolerance in barley.

ABSTRACT: HvAACT1 is a major aluminum (Al)-tolerance gene in barley, encoding a citrate transporter that belongs to the multidrug and toxic compound extrusion (MATE) family. This transporter facilitates citrate secretion from the roots, thereby detoxifying external Al ions-a major constraint of crop production on acidic soils. In this study, we present the outward-facing crystal structure of HvAACT1, providing insights into a citrate transport mechanism. The putative citrate binding site consists of three basic residues-K126 in transmembrane helix 2 (TM2), R358 in TM7, and R535 in TM12-creating substantial positive charges in the C-lobe cavity. Proton coupling for substrate transport may involve two pairs of aspartate residues in the N-lobe cavity, one of which corresponds to the essential As

SUBMITTER: Nguyen Thao T 

PROVIDER: S-EPMC12358922 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature