(f) Wild-type (Fkbp38+/+) and Fkbp38 knockout (Fkbp38−/−) MEFs stably expressing FLAG-Parkin and either EGFP or EGFP-FKBP38 were incubated in the absence or presence of CCCP (30 μM) for 24 h and then stained with allophycocyanin (APC)-labelled annexin V and propidium iodide (PI) for flow cytometric analysis of the percentage of apoptotic cells (annexin V+ and PI+ cells). Data are means±s.d., from three independent experiments. 