Figure 5. Cohesin and CTCF colocalize and separate the active chromatin region from the repressive chromatin region.

The cohesin site at this position is lost in CdLS, thus the silencing epigenetic signal from region 3 is able to migrate into region 2, which harbors ATP11A and downregulates its transcription. (A) Screen shot of ENCODE ENr132 region from the UCSC genome browser is displaying histone methylation and acetylation status, CTCF binding sites, and DNaseI sensitivity sites on this region in GM06990 cells (from Sanger Institute and University of Washington databases, respectively). hSCC1-Control and hSCC1-CdLS are custom tracks. hSCC1-Control track indicates the results of whole genome cohesin binding analysis in LCLs from controls, whereas hSCC1-CdLS track indicates the results of whole genome cohesin binding analysis in LCLs from the CdLS proband; data on CTCF_Bcell2_8 track are adapted from Wendt et al. [10]. (B) Schematic of ENr132 locus as in (A). Five genes located in three regions are displayed. Two cohesin and six CTCF binding sites are shown. Cohesin and CTCF colocalize at Chromosome 13: 112,645,000–112,645,600, which separates region 2 from region 3. Cohesin binding at this position was lost in CdLS proband. (C) ChIP-qPCR validation in three different healthy controls “Normal,” “N6,” and “N12” and three additional CdLS probands “PT2,” “PT12,” and “CDL-017.” Cohesin bound to this locus was dramatically reduced among CdLS probands including a proband with an SMC1A mutation (CDL-017). Sites 1 and 2 are positive controls, site 8 spans Chromosome 13: 112,645,000–112,645,600.