FIGURE 7.

Co-occupation of the H19 ICR by CTCF and Smads requires Smad4. A–D, MDA-MB-468 cells that lack Smad4 were infected with adenoviruses expressing control, LacZ (left bars), or wild type Smad4 (right bars) and were stimulated with TGFβ1 for 4 h (+) or left untreated (−) prior to ChIP with specific antibodies for CTCF (A), Smad2 (B), Smad3 (C), and Smad4 (D). Immunoprecipitated chromatin was amplified with primers specific for the H19 ICR. E and F, input chromatin controls (E) and nonspecific IgG controls (F) are also shown after PCR amplification for the same samples analyzed in A–D.