To evaluate TEC loss and regeneration after AKI, we applied a lineage tracing approach using conditional Pax8.rtTA;TetO.Cre;R26.Confetti (Pax8/Confetti) mice11, enabling a doxycycline-induced random labeling of all TECs by permanent recombination of a single-color-encoding gene (red, yellow, green, or blue fluorescent proteins, RFP, YFP, GFP, and CFP; Supplementary Fig. 1a)12. The gene discussed is CFP; the disease is acute kidney injury.