Overexpressed aurora B is colocalized with cortical actin filaments but not stress fibers in interphase NRK cells. An NRK cell overexpressing aurora B-GFP was stained with rhodamine-labelled phalloidin and then examined the subcelluar localization of aurora B-GFP (a) and actin filaments (c) by confocal laser microscopy. Corresponding phase and merged images (green; aurora B-GFP, red; actin filaments) are shown in panels b and d, respectively. Cortical aurora B-GFP is well colocalized with the short fragments of actin filaments around the cortex (a and d, arrows). However, overexpressed aurora B-GFP appeared not to colocalize with the thick stress actin filaments in the peripheral region of the cortical area (c and d, arrowheads). Bar, 10 μm.