We transfected HCC cells with overexpression plasmids for the DAP3S185A mutant (OE-S185A) and the DAP3S31A mutant (OE-S31A) and then performed a western blot analysis of MT-ND5 expression to clarify the key sites of DAP3 involved in regulating MT-ND5 translation and expression. The gene discussed is DAP3; the disease is hepatocellular carcinoma.