Botany: Programmable Plants by Colorado State University Scientists.
Colorado State University scientists are creating Programmable Plants by designing gene “circuits” that control specific plant characteristics like colour, size, resistance to drought, you name it. The relatively new, interdisciplinary field is synthetic biology – the design of genetic circuits, just like in electronics, that control different functions and can be easily placed in one organism or the next. Most of today’s synthetic biologists work with simple microorganisms, like E. coli or yeast.
A CSU team led by June Medford, professor of biology, and Ashok Prasad, associate professor of chemical and biological engineering, is doing the same thing, but in the much more complex biological world of plants.
“We are quantitatively analysing the gene parts so we can make predictable functions,” Medford said. Using the cell phone analogy, “Apple didn’t go and reinvent a circuit to build the new iPhone; they took an existing circuit and tweaked it,” she said. “Once you have the quantification, and the device physics of the parts characterized, you can use a computer to tell you how to put them together.”
Plants in particular pose a special problem, Prasad added. “Not only is the biology much more complicated than single-celled microorganisms, they are also slow to grow and develop. As a consequence, just testing different genetic circuits becomes a major undertaking.”
Tackling this problem, they’ve invented a method of characterizing not one or two, but hundreds of genetic circuits at a time that control plant functions. They first had to create a blueprint for part construction – the cell parts that make up the eventual circuits. For the testing, they used protoplasts, which are plant cells whose walls have been removed, so they’re little blobs of cytoplasm.
Protoplasts are delicate, though, so the engineers employed mathematical modelling that accounted for all the special properties of each protoplast. Carrying out intensive data analysis and simulations led them to isolate properties of single protoplasts – a major achievement.