Scientists are one step closer to learning how to program cells the way other people program computers.
Researchers led by Christina Smolke, a biochemical engineer at Stanford University, report the accomplishment in the Nov. 26 Science.
Smolke and her colleagues created RNA devices that could rewire cells to sense certain conditions and respond by making particular proteins. Such technology might be harnessed for creating cell-based therapies and cancer-fighting treatments. Someday, scientists might also be able to flip an RNA switch to make plants more tolerant to drought or coax yeast to produce industrial chemicals.
Other researchers have reported building RNA-programming components before, but Smolke’s group is the first to integrate all the pieces into a fully functional system, says Adam P. Arkin, a systems and synthetic biologist at Lawrence Berkeley National Laboratory and the University of California, Berkeley. “It’s sort of like building the first functional car,” says Arkin, who was not involved in the study. “Yeah, combustion was around and there were things that rolled, but actually putting them together” was the real breakthrough.
The new invention is based on eons-old genetic material, RNA molecules. Smolke and her team rigged up RNA molecules that work a bit like a security system that is tuned to be triggered by only one type of intruder. In this case, the RNA molecules detect particular proteins and then turn on or off production of another protein in response.
The team’s first device made human kidney cells glow with a fluorescent protein when the RNA detected a protein from a virus that infects bacteria. Then the researchers got fancier and configured the system so that the cells would kill themselves if the RNA program detected high levels of proteins involved in promoting cancer. These feats, and others, are described in the new study.
These simple programs are just examples of what researchers might be able to make cells do in the future, Smolke says. She envisions that such RNA devices might be used to program animal, plant and fungal cells to do a wide variety of tricks. And the technology could be configured so that multiple conditions need to be met before initiating a program — say, turning on a cholesterol-lowering drug in the liver only after a high-fat meal.
“My sense is that it’s not going to work for everything,” Smolke says, “but it’s going to work for a large subset of things.”