Protein-mediated loops and phase transition in nonthermal denaturation of DNA

نویسندگان

  • Karen G Petrosyan
  • Chin-Kun Hu
چکیده

We use a statistical mechanical model to study nonthermal denaturation of DNA in the presence of protein-mediated loops. We find that looping proteins which randomly link DNA bases located at a distance along the chain could cause a first-order phase transition. We estimate the denaturation transition time near the phase transition, which can be compared with experimental data. The model describes the formation of multiple loops via dynamical (fluctuational) linking between looping proteins, which is essential in many cellular biological processes.

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تاریخ انتشار 2011