1.

DNase-chip detects cell-type-specific DHS 10 kb into the first intron of CFTR. (A) Shown are DHS tracks in four different cell types: CFTR- primary human skin fibroblasts, CFTR+ human bronchial epithelial cell line 16HBE14o- and CFTR+ human colon carcinoma cell lines Caco2 and HT29. Significant peaks representing DHS are apparent in the 5′ promoter region of CFTR+ cells, whereas Caco2 and HT29 cells display another significant DHS within the first intron. Peak height is a measurement of –log10 (P-value) between 0 and 16, as determined by ACME (see Methods). The sequence associated with the identified intronic DHS is shown in panel B. Highlighted sequence corresponds to previously identified positive regulatory element 7/8 [9]. Sequence is numbered based on GenBank reference sequence AC000111. (Sequence corresponds to bases 116916908–116918007 of human genome build 17.) (C) CFTR expression in cell types used in this study measured by RT-PCR analysis compared with a β-glucocerebrosidase housekeeping gene control.