Dr. Leroy Hood talks with participants at the conference. (photo by Dana Johnson)
Keynote speaker strives to unlock mystery of life
In his keynote address on the opening night of the Vanderbilt Conference on Proteomics, Dr. Leroy Hood put into context the current state of biomedical research and projected a vision of how he believes it will be changing in the future.
Hood, considered by some a maverick and by most one of the world’s leading scientists in molecular biotechnology and genomics, believes that the sequencing of the human genome, along with the subsequent efforts to identify and understand the function of the proteins encoded by the genome, will profoundly alter scientists’ view of biology and how biological research is practiced.
“If there is any real frontier facing us in the future,” he said, “it is going to be the ability to acquire diverse types of biological information and integrate them in systems approaches.”
Moving from “discovery science” in which researchers’ findings typically define discrete biological events to “systems biology” where research findings are considered in a dynamic and integrated context, he believes, is necessary to fully understand the complexity of the human body. The payoff of this shift, Hood says, will be a fundamental transformation in predictive and preventive medicine.
Trying to comprehend human biology from a static enumeration of genes and proteins can be likened to trying to build a car from a list of parts. Though a list of the individual components is necessary, it is not by itself sufficient to understand the complexity underlying the engineered object.
Enormous complexity is built into the regulatory systems that control how and when genes are expressed and translated into proteins. The set of proteins found in cells — known as the proteome — is subject to environmental influences, with both predictable and unpredictable outcomes. Scientists can begin to decipher the complexity, Hood says, by carrying out perturbations in model biological systems and testing the nature of the altered “circuit’s” response.
The practice of systems biology requires the application of not just biological experimentation, but also mathematics, engineering, physics, and computer science, to succeed as a whole: to identify the elements of a model; cause perturbations; capture information at the DNA, RNA, protein, protein interaction, and information pathway and network levels; integrate and graphically display that information; and develop mathematical models that will describe the structure and behavior of the system.
Once a system is understood at this level, Hood says, it might be possible to identify critical points in the information network to intervene, or circumvent the limitations of defective genes, with the use of pharmaceuticals.
Hood’s vision of what systems biology can reveal extends beyond what happens in the cell.
“Systems biology will allow us to not only unite the various networks of information at the level of the cell,” he said, “but perhaps to also go on to the level of the individual, the population, and, ultimately, the ecology.”
Hood submits that through the comparative evolutionary information gleaned through studying different organisms, a systems biology approach may yield clues to help “decipher and compare the logic of life.”