Fig. 6. Footprinting of the H-strand promoter region using different primers. The control region 5' to the 12S rRNA was footprinted using the primers HSP 3, HSP 4 and HSP 5 for panels A—C, respectively. With naked DNA as a reference, undermethylated residues are noted by unfilled squares and overmethylated residues are noted by filled squares. Lane assignments were as follows. Panels A and B: 1, in organello anoxia, pH 6.4; 1a, in organello anoxia, pH 6.4; 2, normoxia, pH 6.4; 3, in organello anoxia, pH 7.9; 4, in organello control (normoxia, pH 7.9); 5, naked DNA. Panel C: 1, normoxia, pH 6.4; 2, in organello anoxia, pH 6.4; 3, in organello control (normoxia, pH 7.9); 4, naked DNA. Genomic positions are indicated by arrows.