FIG. 5.

In vivo interaction of CTCF with the recognition site within the chicken α-globin gene domain upstream CpG island. DNA was recovered from the immunoprecipitate after ChIP using chicken CTCF-specific antibodies (44) or preimmune serum (PI). (A) PCR amplification of the 200-bp region with the CTCF-binding site using DNA from ChIP with PI or with CTCF-specific antibodies (CTCF) from 6C2, HD3, and DT40 cells. (B) PCR amplification of the β^A/ɛ enhancer using DNA from ChIP with PI or with CTCF from HD3 and DT40 cells. (C) Linear dependence of PCR product on the quantity of template used. All data are representative of two independent experiments and at least three independent PCR amplifications in the linear range.