Oak Ridge National Laboratory in Oak Ridge, Tenn., in conjunction with the Lawrence Berkeley National Laboratory in Berkeley, Calif., is currently conducting research on RPA, a replication protein that prevents a single strand of DNA (ssDNA) from getting damaged when being unwound from the DNA double helix.
The double helix is essential to DNA as it stores all of the information coding for our genes. Unwinding the double helix is performed so as to read the coding of each strand one base at a time.
Dr. Walter Chazin of Vanderbilt University first suggested conducting research on the protein, and the majority of the data going into the research has been performed in Chazin's own lab at Vanderbilt. Chazin is a Chancellor's Professor of Biochemistry and Chemistry and directs the Center for Structural Biology and the Molecular Biophysics graduate student training program at the university. His research is based on "understanding the structure and movements of proteins and the manner in which they interact with other proteins, DNA and drugs and is funded by multiple grants from the National Institutes of Health."
"RPA was first discovered many years ago and has beed studied for a long time," Chazin said. "But because it is a very complicated protein, knowledge of exactly how it works has been missing all this time. Our study has provided some critical new insights to how RPA works."
Researchers are using a High Flux Isotope Reactor, which uses powerful neutron beams to perform small angle neutron scattering (SANS) experiments using a CG-3 Bio SANS instrument. These experiments give scientists more information on RPA's structure. Chazin's graduate student Chris Brosey and beamline scientist Dr. William Heller collected and analyzed much of the data gathered from the SANS experiments, and Chazin said both were instrumental to the research's current success.
First discovered 30 to 40 years ago, RPA research continues to be conducted, as there is still much to learn about its function and structure.
"This is an ongoing project," Chazin said. "In order to get the whole picture, many different techniques are being used to study RPA, with important roles for x-ray crystallography, Nuclear Magnetic Resonance spectroscopy, small angle x-ray scattering and computer modeling. I brought the problem to RPA."
Chazin said research done on RPA has given new insight into how the protein works, including looking into ways the protein could be used for cancer chemotherapy, an exploratory process currently being conducted at Vanderbilt along with other researchers.
Elizabeth Seydell, junior in zoology at Kent State University, relates the importance of RPA to what she is learning in her major.
“RPAs are important to any organism’s survival,” Seydell said. “Without them, cells wouldn’t be able to replicate. It keeps genetic material moving through generations.”
Julie Kolson, senior transfer student in biomedical engineering at UT, says that the research being conducted is significant for a lot of reasons.
“I know that this research could help cure diseases, because if there was a certain gene of mutation in the DNA you could synthesize new proteins to code for the production of healthy DNA without any defect,” Kolson said. “I didn’t know of any specific research being conducted, but I know that the findings from any research done on RPA are capable of big things.”
Chazin said the research being conducted on RPA will further scientists’ understanding of the way the protein functions and hopes that the data collected can be used for other other medical processes in the future.
“RPA is a member of a class of proteins that cannot be fully understood by standard methods,” Chazin said. “The experiments performed at ORNL and at LBNL represent a new approach to studying how RPA molecules perform.”