Arp3 localisation during mitosis and cytokinesis. HeLa cells were enriched in mitosis after thymidine and RO3306 blocks (see Methods for details). Two hours after release from RO3306 block cells were permeabilised and fixed. Cells were treated for indirect Alexa 555 localisation of Arp3 (a, e, and i) and Alexa 350 localisation of β-tubulin (c, g and k) with specific antibodies. F-actin was visualised with FITC-coupled phalloidin (b, f, and j). Merged images are presented (d, h and l). Images are representative of the different stages of mitosis: anaphase (a-d), late telophase (e-h) and cytokinesis (i-l). Bars, 10 μm.