FIG. 5.
Methylation restricts replication initiation events to sequences within or immediately adjacent to the myc origin. Neutral/neutral 2-D gel electrophoresis of unmethylated or methylated replication intermediates after restriction digestion to generate region A (green), region B (blue), and region C (red). Three typical replication intermediates are depicted: the Y arc, the double Y arc, and the bubble arc (8, 27). Arrowheads indicate the positions of predicted bubble arcs.