Fig. 1. Cytoskeleton interactions in unfixed samples. Triple-label confocal micrograph showing interactions of microtubules (red), F-actin (green), and cytokeratin (blue) in an unfixed aster. All three systems could be found in close proximity to each other (arrows). Microtubule—F-actin associations could be observed in the absence of cytokeratin (arrowheads), and microtubule-cytokeratin interactions in the absence of F-actin (chevrons).