Plectoneme formation in DNA

Overtwisted garden hoses, electrical wires, and ropes form plectonemes, supercoiling to lower their twist energy. In Michelle Wang's lab they overtwist DNA, to form the same plectonemes on a single-molecule basis.

Bryan Daniels aided in the interpretation of the experiment (PRL), generated a theory for the resulting jumps (PRE), and worked out the theory for the thermal nucleation of plectonemes under torque, (PRE).

Last Modified: February 15, 2013.

This work supported by the Division of Materials Research of the U.S. National Science Foundation, through grant DMR-070167 and DMR-1005479.

Statistical Mechanics: Entropy, Order Parameters, and Complexity, now available at Oxford University Press (USA, Europe).