Researchers have captured supercoiled DNA with unprecedented detail.
A new three-dimensional structure of a supercoiled DNA that goes into incredible detail is helping researchers see just how dynamic this building block of life is.
The shape is much more dynamic than the traditional double helix we’ve come to know as representative of DNA, and they were recently imaged using a powerful microscopy technique, according to a Phys.org.
Researchers at Baylor College of Medicine, who used supercomputer simulations at the University of Leeds, published a study in the journal Nature Communications about simulations that show just how dynamic DNA is, wiggling and changing its shape, rather than simply acting as a static double helix strand.
It’s important for scientists to understand this as it can lead to designing better medicines or more effective cancer treatments. Why? Because drug molecules often rely on recognizing molecular shapes, like a key fits into a lock.
The double helix shape is how DNA is typically presented, but DNA is much more complicated than any static representation. Its structure was first defined by James Watson and Francis Crick in 1953, leading to the popular image we are familiar with when we hear the term DNA, but the two men were actually describing just a tiny part of the genome, and just one turn of the double helix. Their research covered about a dozen “base pairs,” forming the famous twisting ladder shape, but this latest study looks at hundreds of base pairs, and by doing so the shape begins to change dramatically.
Of course, even these researchers aren’t going far enough. Scientists estimate that there are a whopping 3 billion base pairs that complete a set of DNA, which measures about three feet in length, a massive string that must be coiled up so tightly that it can be squeezed into a cell’s nucleus. To study this DNA structure, scientists must replicate this coiling.
Researchers basically wound and unwound tiny DNA circles just a single turn at a time, then devised a test to make sure they acted in the same way as full-length DNA strands.