When the Wright brothers launched themselves into the history books, they used a plane that was made up of perhaps 2,000 parts. And it was quite susceptible to the vagaries of wind, light, and weather, unlike the robust commercial airplanes of today, which are constructed on a scale that is several orders of magnitude greater.
And so it is with biological systems, Hiroaki Kitano, a leader in the growing field of systems biology, argues — at least among the lower orders. Mycoplasma genitalium, with fewer than 500 genes, does not have nearly the adaptability of Escherichia coli, with 4,000. This element of robustness, he said — the degree to which an organism is adaptable and flexible within its environment — is “one of the most essential features of biosystems,” and of our understanding of how they work.
Speaking at the CHI Drug Discovery conference held in Tokyo, Japan, January 28-30, Kitano discussed his efforts at developing systems biology as a field, including organizing an annual conference and the Kitano ERATO Symbiotic Systems Project, conducted in collaboration with the California Institute of Technology.
Unlocking the mysteries of how entire biological systems function has been a recurring theme of science, but it is only now, Kitano said, that “we have sufficient knowledge to ground knowledge down to the cell level.”
Images of his work elucidated the point. Kitano showed video of a single C. elegans cell dividing, the data from which was further used to build an animated simulation. One goal is to create an image library of cell lineage — tracing the varied development of cells with genes knocked out. The group aims to record 500 such lineages per year.
Kitano is also looking forward to the day when microscopic imaging of the development process will be fully automated.
Mapping, whether for understanding development or maintenance, can also provide an important tool, Kitano said, and may lead to new drug design techniques or reveal ways to minimize side effects. Current maps may outline pathways and structure, but what systems biology is attempting to do, Kitano said, is to delineate the “traffic flow” and other dynamics. “If you’re in the delivery business,” he said, “you need to plan your routes.”
There is enormous potential for modeling, he concluded, as well as enormous challenges — it is not simply a matter of collecting data, building the model, and creating something new. Analysis methods and sensitive measuring devices remain significant hurdles, but the greatest progress, he suggested, will come from uncovering the right theories to govern the growing field.
— Sara Harris, Tokyo