Fig. 1. Visualisation of _m loss in non-irradiated mitochondria following partial irradiation of cells with filamentous and discrete punctate morphology of mitochondria. (A) Confocal imaging of two human osteosarcoma 143B cells before (0 seconds) and at end of partial irradiation (128 seconds) either treated without or with CCCP (20 µM for 60 minutes followed by 60 minutes recovery in the absence of CCCP), which induces punctate morphology. Both cells were loaded with _m indicator Rh123 (10 µM) and photosensitiser CMXRos (200 nM) prior to irradiation. The area of irradiation is indicated by the dashed box. Loss of _m in filamentous and punctate mitochondria is representative of that in 18 of 21 cells without CCCP and 8 of 9 cells after CCCP treatment and recovery. (B) Confocal images of a 143B cell stably expressing MtGFP before (left) and after (right) treatment with CCCP followed by recovery. Bars, 10 µm.