Fig. 6. Suppression of DNA replication by EcoRI-treatment. Demembranated
Xenopus sperm nuclei were incubated for 90 minutes at 23°C in the
extract with or without EcoRI, caffeine and geminin in the presence
of [
-32P]dCTP. The extent of DNA synthesis is represented as
a percentage of accumulative DNA synthesis after a 90 minute incubation in the
absence of DNA damaging agents. 100% DNA synthesis is estimated to be an
amount equivalent to the duplication of about 90% of input DNA.