Functional CTCF sequence motifs at the intronic region of the IGF2BP1 gene. (A) UCSC Genome Browser display of relative positions of high- and low-confidence CTCF target motifs, ChIP-chip, ChIP sequencing (ChIP-seq) and ChIP self-organizing maps results. (B) Ywt 105-bp and YwtZwt 125-bp templates employed in the immobilized template assay. Detailed sequences of the templates are shown in Figure S9 in Additional file 2. (C) Western blot analysis of CTCF recruitment to Ywt 105-bp and YwtZwt 125-bp templates containing combinations of wild-type and mutated CTCF target sequences. Motif Y is sufficient for recruitment of CTCF.