# How dsDNA breathing enhances its flexibility and instability on short length scales 

O-chul Lee, ∗ Jae-Hyung Jeon, † and Wokyung Sung ‡ 

Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea 

(Dated: October 30, 2018) 

## Abstract 

We study the unexpected high flexibility of short dsDNA which recently has been reported by a number of experiments. Via the Langevin dynamics simulation of our Breathing DNA model, first we observe the formation of bubbles within the duplex and also forks at the ends, with the size distributions independent of the contour length. We find that these local denaturations at a physiological temperature, despite their rare and transient presence, can lower the persistence length drastically for a short DNA segment in agreement with experiment. 

PACS numbers: 87.14.gk, 87.15.A-, 87.15.hg 

