IOWA CITY, Iowa -- A University of Iowa research team has developed a way to isolate replicating deoxyribonucleic acid (DNA) molecules that scientists then can use to examine the replication process under controlled conditions. This advance will allow investigators to better understand DNA replication and may lead to improved therapies for treating diseases such as cancer.
"One of the difficulties with studying the DNA replication process is that there are multiple protein complexes involved, and it is difficult to experimentally dissect individual reactions that are occurring," said Marc Wold, Ph.D., UI associate professor of biochemistry and the project's principal investigator. "Our procedure will allow us to examine these reactions in more detail."
DNA is the genetic material that encodes all components in human cells. Each cell contains more than two meters of DNA. Every time a cell divides, it is necessary to duplicate all of its DNA.
Using DNA derived from the Simian Virus 40 from monkeys, Wold and members of his laboratory let DNA replication start in an extract from human cells. The researchers attach magnetic beads to the DNA molecules and use a magnet to isolate the molecules and associated replication proteins. The researchers can then manipulate the extracted DNA and add specific replication proteins in a controlled manner to understand the mechanics of DNA replication.
"This will mean we can start asking specific questions about the reactions during replication and learn more about the specific roles of replication proteins," Wold said.
The advantage of this system is that it allows separation of the DNA replication process from the synthetic reactions. This separation has been difficult to achieve in previous replication systems.
Using his technique, Wold hopes that his lab and others can begin to understand what causes some cells to mutate. DNA replication is a complex process that is very accurate and highly regulated. Errors in DNA replication can lead to cell mutations, which contribute to diseases such as cancer, and can cause cell death, Wold said.
"If we can use our system to look at how mutations occur, it gives us the potential to make more effective drugs for treating cancer," Wold said.
Wold's work appeared in a recent issue of the journal of Nucleic Acids Research.
Journal
Nucleic Acids Research