High-resolution structure of AKR1a4 in the apo form and its interaction with ligands

Aldo-keto reductase 1a4 (AKR1a4; EC 1.1.1.2) is the mouse orthologue of human aldehyde reductase (AKR1a1), the founding member of the AKR family. As an NADPH-dependent enzyme, AKR1a4 catalyses the conversion of D-glucuronate to L-gulonate. AKR1a4 is involved in ascorbate biosynthesis in mice, but has also recently been found to interact with SMAR1, providing a novel mechanism of ROS regulation by ATM. Here, the crystal structure of AKR1a4 in its apo form at 1.64 angstrom resolution as well as the characterization of the binding of AKR1a4 to NADPH and P44, a peptide derived from SMAR1, is presented.