ABT-737 and NIX differ in their requirement for BAX or BAK. (Left panels) Flow cytometry of reticulocyte-enriched blood from phlebotomized Bax^−/−;Bak^−/−, Atg7^+/+, Atg7^−/−, and Nix^−/− mice cultured for 3 days and doubly stained with MTR and TO. Genotypes are indicated on the left. (Right panels) Flow cytometry of the same blood samples, cultured for 1 day in the presence (shaded area) or absence (black line) of ABT-737, and stained with MTR.