Fig. 4: Molecular interactions among MG53, zinc, and ADH/ALDH2 in alcohol metabolism.

A Molecular docking analysis of MG53 binding to ADH and ALDH2. MG53 binds to ADH at residues 87, 100, and 101 (left), and binds ALDH2 at residue 103 (right). B Molecular dynamic simulation of MG53-ADH and MG53-ALDH2 complexes for 100 ns. Left: Gibbs free energy landscape of the MG53-ADH complex, with principal component 1 (PC1) ranging from 0.0 to 1.13, and PC2 between 2.97 and 3.23. Right: Gibbs free energy landscape of the MG53-ALDH2 complex, with PC1 values from 0.0 to 1.05, and PC2 values between 2.71 and 3.03. C Root Mean Square Deviation (RMSD) trends of MG53-ADH (blue) and MG53-ALDH2 (red) complexes, showing a rapid increase from 0 to 20 ns, followed by stabilization from 20 to 100 ns. D Binding affinity of rhMG53 to ADH (left) and ALDH2 (right) measured at various concentrations of MG53. ADH/ALDH2 were immobilized on streptavidin (SA) biosensors, and binding was detected by bio-layer interferometry. E Binding process of rhMG53 protein (10 μg/ml) and rhMG53-ADH-binding mutant (rhMG53-3A) to ADH, analyzed by bio-layer interferometry. ADH was immobilized on SA biosensors. rhMG53-3A protein represents MG53 mutations at ADH-binding residues 87, 100, and 101. (F) ADH enzyme activity in AML12 cells co-cultured with 400 mM EtOH and treated with 10 μg/m lrhMG53 or rhMG53-3A (n = 8 per group). G Binding process of rhMG53 and rhMG53-ALDH2-binding mutant (rhMG53-1A) to ALDH2, analyzed by bio-layer interferometry. ALDH2 was immobilized on SA biosensors. rhMG53-1A represents MG53 mutation at the ALDH2-binding residue 103. H ALDH2 enzyme activity in AML12 cells co-cultured with 400 mM EtOH and treated with 10 μg/ml rhMG53 or rhMG53-1A (n = 8 per group). ADH enzyme activities (I) ALDH2 enzyme activities (J) cell viability (K) and intracellular LDH release (L) in AML12 cells co-cultured with 400 mM EtOH and treated with 10 μg/ml rhMG53 or rhMG53-zinc-binding mutant (rhMG53-C29L/C105S), representing mutations in MG53-zinc-binding domains at residues 29 and 105 (n = 8 per group). Data were presented as mean ± SD. P-value was determined by one-way ANOVA with Tukey’s test. Source data are provided as a Source Data file.