Just when you though DNA couldn’t get any weirder (we’ve touched on it’s weirdness before), researchers at the Gladstone Institutes have discovered that it bursts proteins from its innards in rapid fire succession, rather than lazily churning it out as previously thought.
First, a bit of background. DNA, located at the center of every cell, is an incredibly large and complex spiral molecule. Pieces of the DNA, called genes, can be switched on by molecular signals. It was previously thought that the genes just stayed turned on, but recent experiments suggested otherwise, leading to the current experiment.
Once the DNA opens up, the code is transcribed to a new strand of genetic material, called RNA, which is then transported “protein factories” in the cell, called ribosomes. Here, relatively small molecules, called amino acids, latch onto the strand of RNA, connect to one another, and transform into a protein.
The proteins, in turn, go on to become messengers, building blocks, molecular machines, and various other amazing things that are the envy of nanotechnology the world over.
In the meantime, we have also discovered that DNA sends signals back and forth to itself, constructing elaborate networks, and genes can even jump up and down the strand. Furthermore, proteins themselves are “smart” on some level, and can even regulate access to the genetic code.
Leor Weinberger and his colleagues wanted to respond to recent research that suggested the process of gene activation occurs in short bursts, rather than over extended periods.
To accomplish this, they inserted a florescent green protein into white blood cells’ genetic code. These proteins latched onto the cell’s DNA, so that they would glow green whenever that piece of the genetic code was activated.
The DNA lit up and flickered like a strobe light, firing off strands of RNA in rapid fire succession. This bursting increased in frequency for as long as protein was needed, until a threshold was met. If still more protein was needed, the the bursts would go on for longer, then shut off when no more proteins were needed.
This bursting process apparently allows the cell to regulate how rapidly proteins are introduced, which likely influences the role that those proteins will play as well.