Anti-Mcm7 (yN-19, sc-6688, Santa Cruz), anti-Orc6 (SB49). Psf2- FLAG was visualized with ANTI-FLAG M2-peroxidase (Sigma), Mcm10 was detected using the T7-tag antibody (69522, Novagen), Dbf4 was visualized with an anti-CBP tag antibody (07-482 Merck Millipore) and Rpa1 was detected with anti-scRPA (AS07 214, Agrisera). Psf1 antibodies were a gift from K. Labib. Polyclonal antibodies against Sld3, Sld7, Sld2, Cdc45 and Dpb11 were described previously6 (link). Polyclonal antibodies against the Dpb2 subunit of pol ε were raised against full-length protein, and their specificity was confirmed using purified pol ε.