Replication Pausing and Imprinting Figure 7. Characterization of the cis-acting region required for replication pausing. (A) DNA sequence of the abc region, aligned to the corresponding sequence in the P cassette, is given. The borders of a, b, and c regions are indicated by double arrows above the sequence. The sequence was divided into 10 segments and each segment was substituted by a random DNA sequence and denominated as substitution 1 to 10 (Sub1-10). (B) 2D-gel analysis of plasmids that carry different substitutions within the abc region. Top left, line drawing of the parent plasmid. The PLoS Genetics | www.plosgenetics.org 11 March 2011 | Volume 7 | Issue 3 | e1001328