Figure 4From: DNA fragments binding CTCF in vitro and in vivo are capable of blocking enhancer activityRelative DNA content of three constructs: pPNT/E-CTCF7-mP that contains the CTCF7 fragment between the promoter and enhancer, pPNT/EmpS-CTCF7 that contains the CTCF7 fragment outside the promoter-enhancer pair, and pPNT/E-l-mp--the control construct with a lambda DNA fragment inserted between the promoter and enhancer in genomic DNA of CHO cells after positive-negative selection. The relative content was estimated by real-time PCR based on the difference between the number of PCR cycles required to detect the target (for detail, see Methods).Back to article page