Fig. 2: Structural basis for urate recognition by GLUT9.

a The cut-open representation of the surface electrostatic potential of GLUT9-UA complex. b Coordination of UA, shown as pink ball and sticks, by central cavity residues. The residues in direct contact with UA are shown as sticks. c Plane diagram of residues constituting the binding pocket within the cut-off distance from UA of 5 Å. The direct H-bonds are indicated by red dashed lines in (b, c). And this is applied in all the figures for interaction analysis. d H-bond and π–π interactions between GLUT9 and urate were maintained for more than 30% throughout the simulation. e Whole-cell patch clamp recordings were performed to validate the residues involved in urate binding. n is the number of experimental cells from which recordings were obtained. And n = 6, 10, 8, 8, 7, 9, 8, 8, 7, 4 for wildtype (WT), W336A, Y327A, I209A, L332A, V213A, E364A, C210A, N462A, F426A, respectively. Data are mean ± SEM. ***p = 0.0001 versus WT, ****p < 0.0001 versus WT. Statistical significance was assessed using one-way ANOVA analysis. f Microscale thermophoresis (MST) measurement about the binding affinities of GLUT9 variations with urate. n represents the replicates number of the experiment, and n = 6, 6, 5, 3, 4 for WT, N333A, E364A, Y327A, W336A, respectively. Data represent mean ± SEM.