General laboratory chemicals were obtained from Sigma-Aldrich and Thermo Fisher Scientific. Antibodies to Cep55 (1–222 aa), Cep55 pS436 (peptide antigen, ALNEpSLVE; sheep only), MKlp1 (24–146 aa), Vps4 (1–129 aa), and MKlp2 (63–193 aa) were raised in sheep and rabbit using peptides or hexahistidine-tagged human proteins expressed in and purified from bacteria. Specific antibodies were purified using the antigens conjugated to Affigel-15, eluted with 0.2 M glycine, pH 2.8, then dialyzed against PBS before storage at −80°C. Rabbit antibodies to Plk1, astrin, PRC1, PRC1 pT602, and MKlp1 pS911 have been described previously (Neef et al., 2003 (link), 2006 (link), 2007 (link); Thein et al., 2007 (link)). Commercially available antibodies were used to α-tubulin (mouse DM1A; Sigma-Aldrich), Plk1 (mouse SC-17783; Santa Cruz Biotechnology, Inc.), aurora B (mouse AIM1; BD), and cyclin B1 (mouse GNS3; Millipore). Kinase inhibitors were obtained from Sigma-Aldrich (5 mM flavopiridol 1,000× stock and 1 mM GW843862 1,000× stock), Tocris Bioscience (100 mM ZM447439 10,000× stock), and Axon Medchem (1 mM BI2536 1,000× stock).