CONTACT: JENNIFER CRONIN
2130 Medical Laboratories
Iowa City IA 52242
(319) 335-5661; fax (319) 335-9917
Release: March 31, 1999
UI laboratory develops procedure to study mechanism
of DNA replication
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
"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
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's work appeared in a recent issue of the journal
of Nucleic Acids Research.