All life on Earth relies, ultimately, on the delicate coordination of switches. During development, these switches turn genes on—or keep them off—at precise intervals, controlling the complex processes that guide the growth of the embryo, cell by cell, as it matures from a collection of stem cells into a living, breathing organism.
If you control the switch, you could theoretically control some of life’s most fundamental processes.
Which is precisely what scientists at Cornell University are attempting to do.
Reporting in today’s issue of Nature Chemical Biology, synthetic biologists have developed a new method of directing these switches—a feat that could revolutionize the field of genetic engineering.
At the heart of the team’s discovery is a tiny molecule called RNA. A more simplified version of its cousin, DNA, RNA normally serves as a liaison—translating the genetic information housed in DNA into the proteins that together make up each and every cell in the body.
In nature, RNA does not have the ability to ‘turn on’ a gene at will. So the Cornell team, led by Julius Lucks, made a new kind of RNA that did.
They engineered a new type of RNA that they are calling Small Transcription Activating RNAs, or STARS, that can serve as a kind of artificial switch. In laboratory experiments, Lucks and his team showed that they could control how and when a gene was switched on by physically placing the STARS system in front of it. As Lucks explained in a news release:
“RNA is like a molecular puzzle, a crazy Rubik’s cube that has to be unlocked in order to do different things. We’ve figured out how to design another RNA that unlocks part of that puzzle. The STAR is the key to that lock.”
RNA is an attractive molecule to manipulate because it is so simple, says Lucks, much simpler than proteins. Many efforts aimed at protein manipulation have failed, due to the sheer complexity of these molecules. But by downshifting into the simpler, more manageable RNA molecules, Lucks argues that greater strides can be made in the field of synthetic biology and genetic engineering.
“This is going to open up a whole set of possibilities for us, because RNA molecules make decisions and compute information really well, and they detect things really well,” said Lucks.
In the future, Lucks envisions a system based solely on RNA that has the capability to manipulate genetic switches to better understand fundamental processes that guide the healthy development of a cell—and provide clues to what happens when those processes go awry.