Soliton-like base pair opening in a helicoidal DNA: An analogy with   helimagnet and cholesterics
  We propose a model for DNA dynamics by introducing the helical structure through twist deformation in analogy with the structure of helimagnet and cholesteric liquid crystal system. The dynamics in this case is found to be governed by the completely integrable sine-Gordon equation which admits kink-antikink solitons with increased width representing a wide base pair opening configuration in DNA. The results show that the helicity introduces a length scale variation and thus provides a better representation of the base pair opening in DNA. 
M. Daniel and V. Vasumathi