A log phase culture of fox lung fibroblast cells was labeled for F-actin and the intracellular mitochondrial network with Alexa Fluor 488 conjugated to phalloidin and MitoTracker Red CMXRos, respectively. DRAQ5 (pseudocolored cyan), a far-red fluorescent DNA probe, was employed as a nuclear counterstain. Images were recorded with a 60x oil immersion objective using a zoom factor of 4.5 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, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles unless otherwise noted above.