A DNA Twist Diffuses and Hops

摘要

Perhaps the reader can remember the good old days of wired phones, their cords so prone to the absent-minded twisting that eventually produced a multitude of small coiled coils. Wired phones are a thing of the past, but their cords still serve as inspiration to those interested in the coiling process of DNA. The striking beauty of DNA coiling (aptly named supercoiling) was first illustrated when Vinograd et al. (1) discovered multiple intertwined loops in their electron microscope images of a circular DNA from the polyoma virus. These loops, also called plectonemes, can play an important role in gene regulation by bringing together distant DNA elements, such as enhancers and promoters (2). On page 94 of this issue, van Loenhout et al. (3) use single-molecule techniques to uncover the rich dynamics of plec-toneme formation and movement.