Correlative analysis of CREB and CREM binding site occupancy. A. Association of CREB, pol II and H3K4me3 in GC1-spg cells. Comparison of pol II and H3K4me3 tag density in the region of +/- 5 kb around the CREB-occupied loci. Clustering analysis identifies 3 classes, A; CREB loci with low or no pol II and H3K4me3, B-C; CREB loci with high pol II and H3K4me3 corresponding to transcription on the sense and anti-sense strands, respectively. B. Comparison of CREM tag density in the region of +/- 5 kb around the CREB-occupied loci. Clustering identifies 2 groups A; CREB loci with low or no CREM and B; CREB loci with high CREM. C. Venn diagramme comparing common and cell-specific CREB/CREM occupancy of binding sites using the CREB data in panel B and the equivalent analysis of the CREM occupied loci (data not shown).