Fluorescence images of control and Si-RNA transfected HeLa cells treated with Taxol for 5 min. Mitotic cells were stained for alpha-tubulin (top row, green)or NuMA (center row, red). Cohesin depletion inhibits Taxol-induced spindle asters in vivo. Cells were observed with an Olympus IX70 microscope and recorded with a Magnaview CCD camera. See Fig 4D in Kong et al., 2009, Mol Biol Cell 20:1289-1301.