Fig. 2.
From: Identification of two novel elements involved in human MUC1 gene expression in vivo
DNase I hypersensitive sites at −750 bp and −250 bp with respect to the transcriptional start site of the human MUC1 gene in HPAF chromatin. (A) Map of region. Arrows above the line denote the DHS positions. Restriction sites shown below the line are B = BamH I, Bs = BsrG I, S = Sac I. Below the line are shown the probes (hatched) and the subfragments produced by DHS. (B) Southern blot of DNase I digested HPAF chromatin cleaved with BamH I and hybridised with 5′ MUC1 probe. Lanes 1 (0°C) and 2 (37°C) show DNA prepared from nuclei which had not been treated with DNase I. Lanes 3–5 show DNA prepared from nuclei treated with increasing amounts of DNase I; (Lane 3, 20 units; Lane 4, 40 units; Lane 5, 80 units DNase I). The detection of the DHS in lane 2 is probably due to endogenous DNase I activity at 37°C.