DNA — Now in 3D!

Researchers have been looking for a way to find out how proteins bind to DNA packets, but so far have only been able to speculate, writes Katherine Harmon in Scientific American's Observations blog. But now, researchers at Penn State use x-ray crystallography to visualize the protein binding for the first time in 3D. The group used the RCC1 enzyme, which helps separate chromosomes when a cell divides, to bind to fruit fly DNA, Harmon says, and their results (which were published in Nature) showed that RCC1 binds to opposite sides of the nucleosome. The researchers say this puts us a step closer to knowing how cells read DNA and regulate genes.