Iris Hood

Unwinding the Mystery of DNA

By Stacy Kish on August 4, 2010

“All living cells must replicate their genetic material before cell division,” begins Iris Hood, a doctoral candidate at the University of California, Berkeley and a DOE Office of Science Graduate Fellow. “My work will highlight how an essential molecular interaction network helps to control the ability of a bacterial cell to grow and replicate.  Understanding the mechanisms that make this happen could have important implications for society in terms of bioremediation and biofuel production, technologies which both utilize bacteria.”

Hood is working to uncover the mechanisms that initiate DNA replication. “It all begins when proteins called helicases are deposited onto the DNA at a replication start site,” she begins. The helicase unwinds the DNA strands so other molecular machines can begin duplicating the genetic material. The mystery Hood is trying to solve is how helicases become deposited in the correct location and orientation onto DNA?

To tackle this problem Hood has purified E. coli proteins and modified a DNA substrate with a fluorescent substance that will ‘light up’ in response to helicase activity.  “My research will merge molecular-level structural details with a novel biochemical assay that is capable of probing the dynamics of this system.”

“My research utilizes tools that are necessary to understand how biomolecules interact with one another in space and time and to eventually develop means of controlling these interactions,” said Hood. This work has the potential to clarify helicase-loading mechanisms that can be applied to all cellular organisms.

Hood concludes, “The DOE Fellowship will make it possible to continue my graduate work at one of the best schools in the country and attend conferences where I can share my research with other experts in the field.”

Stacy Kish is a Science Writer with the Office of Science.