A log phase culture of PtK2 epithelial cells was labeled with MitoTracker Red CMXRos to target the mitochondrial network and Alexa Fluor 488 conjugated to phalloidin, which binds to the filamentous actin cytoskeleton. In addition, the cells were treated with TO-PRO-3, which exhibits affinity for DNA, in order to counterstain the nucleus. Images were recorded with a 60x oil immersion objective using a zoom factor of 3.5 and sequential scanning with the 488-nanometer spectral line of an argon-ion laser, the 543-nanometer line from a green helium-neon laser, and the 633-nanometer line of a red helium-neon laser. During the processing stage, the Alexa Fluor 488 image channel was pseudocolored blue, while the MitoTracker Red CMXRos image channel was pseudocolored red and the TO-PRO-3 channel was pseudocolored green.