Plasmids bearing mammalian DNA-replication origin-enriched (ors) fragments initiate semiconservative replication in a cell-free system.

Four plasmids containing monkey (CV-1) origin-enriched sequences (ors), which we have previously shown to replicate autonomously in CV-1, COS-7 and HeLa cells (Frappier and Zannis-Hadjopoulos (1987) Proc. Natl. Acad. Sci. USA 84, 6668-6672), were found to replicate in an in vitro replication system using HeLa cell extracts. De novo site-specific initiation… CONTINUE READING