FIG. 9.

In vivo footprinting of the M-MuLV LTR minus strand. Infected 43-D fibroblasts and thymic tumor cells treated in vivo or in vitro with DMS were analyzed by cleavage and LMPCR by using the minus-strand-specific primers shown in Fig. 8A. Arrows indicate bases hypersensitive to in vivo DMS methylation in each respective cell type. DNA templates were the same as those used for the sense-strand analysis.