image: In previous research, Rice synthetic biologist Jeff Tabor and colleagues created colonies of light-sensitive bacteria that exhibited complex patterns when exposed to images, like this portrait of Albert Einstein. In coming research, Tabor and colleagues at Rice and University of Washington plan to insert genes that will allow the bacteria to grow into complex shapes on their own. view more
Credit: Matt Good and Jeff Tabor
HOUSTON -- (Sept. 12, 2011) -- Sometimes it's good to start with a clean slate.
That's the idea behind a new four-year, $2 million research program at Rice University and the University of Washington that aims to push the boundaries of synthetic biology by modifying run-of-the-mill bacteria with sophisticated genetic circuits. Researchers say their plan to create bacteria that form geometrical patterns could help scientists better understand the behavior of stem cells.
"In complex creatures like humans and animals, cells cooperate to form extraordinary patterns and structures from the earliest stages of embryonic development," said Rice bioengineer Jeff Tabor, the principal investigator for the new project. "We want to understand the genetic programming that makes this possible, but these cells are so complex -- and there is so much going on biochemically -- that it's hard to focus on just the piece we want."
Tabor said Escherichia coli (E. coli) provides the researchers with a "blank slate" because colonies of the bacteria don't normally exhibit patterned growth. "By inserting specific genetic circuits into E. coli -- for example, genes that cause them to grow in star patterns -- we can focus on just one piece of a much larger genetic picture."
Rice bioengineer Oleg Igoshin, who specializes in computational bioengineering, said, "The question is really about how much we can control. Can we create a genetic program that forces the overall system into a given geometric pattern?"
Igoshin and Tabor said the feedback between experiment and computational modeling is crucial to the success of the four-year project.
"Accomplishing simple patterns may be possible with intuition, but we will need computational models that are grounded in underlying theory to achieve the kind of complexity that we're aiming for," said Igoshin, assistant professor of bioengineering.
Tabor's co-principal investigators on the four-year program, which was recently awarded a competitive grant from the National Science Foundation, are Igoshin and University of Washington researchers Eric Klavins, Ben Kerr and Georg Seelig. The five come from disciplines as diverse as electrical engineering and evolutionary biology. Tabor said such diversity can be beneficial in synthetic biology, a new field of study that centers upon engineering biological functions not found in nature.
"Synthetic biology has come a long way in the past decade," said Tabor, assistant professor in bioengineering. "There have been significant advances in engineering cells that can sense and react to one another or to external stimuli like light.
"The next big challenge is to build upon those techniques to program cells that can cooperate with one another in complex, coordinated tasks."
Igoshin and Tabor are each faculty investigators at Rice's BioScience Research Collaborative (BRC), and BRC Scientific Director Cindy Farach-Carson said the grant award highlights Rice's growing prominence in synthetic biology.
"Understanding how living systems form patterns in nature can have a huge payoff in the development of new technologies that will improve our world," said Farach-Carson, Rice's vice provost for translational bioscience. "Imagine a world where we can control how living cells behave. Departments in Rice's schools of Natural Science and Engineering have been working together to recruit the best and brightest scientists to work toward this goal, and this award highlights the success of this recruiting effort."
A copy of the NSF grant abstract is available at: http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=1137266