Purification and functional inactivation of the fission yeast MCMMCM-BP complex

► Fission yeast MCMMCM-BP complex comprises Mcb1 and the Mcm3-Mcm7 proteins. ► Mcm2 is not a component of the MCMMCM-BP complex. ► Mcb1 inactivation leads to accumulation of Rad22 DNA repair foci. ► Mcb1 inactivation leads to Chk1-dependent checkpoint activation and cell cycle arrest. ► Mcb1 is required for successful meiosis.