In vitro cell cycle arrest induced by using artificial DNA templates.
In cell extracts of Xenopus eggs which oscillate between S and M phases of the cell cycle, the onset of mitosis is blocked by the presence of incompletely replicated DNA. In this report, we show that several artificial DNA templates (M13 single-stranded DNA and double-stranded plasmid DNA) can trigger this feedback pathway, which inhibits mitosis. Single-stranded M13 DNA is much more effective than double-stranded plasmid DNA at inhibiting the onset of mitosis. Furthermore, we have shown that low levels of M13 single-stranded DNA and high levels of double-stranded plasmid DNA can elevate the tyrosine kinase activity responsible for phosphorylating p34cdc2, thereby inactivating maturation-promoting factor and inhibiting entry into mitosis. This constitutes a simplified system with which to study the signal transduction pathway from the DNA template to the tyrosine kinase responsible for inhibiting p34cdc2 activity.
Kornbluth
S
S
Department of Biology, University of California, San Diego, La Jolla 92093.
Smythe
C
C
Newport
J W
JW
D000818:Animals; D002110:Caffeine / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects / Q000502:physiology*; D016213:Cyclins / Q000494:pharmacology; D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004789:Enzyme Activation; D016200:Maturation-Promoting Factor / Q000378:metabolism; D008938:Mitosis; D010766:Phosphorylation; D010957:Plasmids; D006656:Protamine Kinase / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism*; D015398:Signal Transduction; D014981:Xenopus
D016213:Cyclins; D004277:DNA, Single-Stranded; D002110:Caffeine; D011494:Protein Kinases; D006656:Protamine Kinase; D016200:Maturation-Promoting Factor