Members of the MCM2-7 family co-localize with RNA Pol II at the loci of constitutively transcribed genes. A, map of the GAPDH gene and primers used for ChIP analysis against the 5′ region and the center (C) of the gene. B and C, 2fTGH cells were grown in 15-cm dishes to about 80–90% confluence. ChIP assays were performed using anti-MCM3, anti-MCM5, and anti-RNA Pol II antibodies. PCR reactions used primers against the 5′ region or the center of the GAPDH gene. C, results were quantitated using a PhosphorImager and expressed as ChIP/Input. D, ChIP assays were performed for 2fTGH cells with anti-Stat1, anti-MCM2, anti-MCM3, anti-MCM5, and anti-RNA Pol II antibodies. One 15-cm dish was used for the Stat1, MCM2, and MCM3 ChIP (lanes 1–3), and a second dish was used for the MCM5, RNA Pol II (lanes 4 and 5), and Stat1 ChIP. The result of one Stat1 IP (lane 1) is shown. Input A (lane 6) corresponds to the Stat1, MCM2, and MCM3 ChIP (lanes 1–3), and Input B (lane 7) corresponds to Mcm5 and RNA Pol II (lanes 4 and 5). Primers correspond to the centers of the β-actin, E2F4, and β-tubulin genes. E, signals in D were quantitated with a PhosphorImager, and values are expressed as ChIP/Input. Results represent at least three independent experiments.