In protein expression, there is a reduction of GOT2 and GPT2 enzyme proteins in CKD3/4 versus control in the cortex (both P < 0.05, Supplementary Fig. 5D, E), and GPT2 protein in both CKD groups versus control in the medulla (P < 0.05, Supplementary Fig. 5F). The gene discussed is GPT2; the disease is chronic kidney disease.