Figure 2.

Possible relationships between DNA replication and the nuclear matrix (NM). (A) DNA is thought to be periodically attached to the NM at S/MARs forming intervening chromatin loops. (B) Refined model illustrating variable loop sizes and complex S/MAR usage including utilized S/MARs and function-related alternative potential S/MARs. (C) Our preferred model showing attachment to the NM via nonorigin S/MARs, and recruitment of DNA replication origins at G1/S-phase with possible impact on loop size. (D) Alternative representation of chromatin loops showing replication origin clustering within a DNA replication factory, with no representation of NM attachments.