Hwa Terence, Marinari Enzo, Sneppen Kim, Tang Lei-han
Department of Physics and Center for Theoretical Biological Physics, University of California at San Diego, La Jolla, CA 92093-0319, USA.
Proc Natl Acad Sci U S A. 2003 Apr 15;100(8):4411-6. doi: 10.1073/pnas.0736291100. Epub 2003 Apr 2.
We study the thermodynamic and dynamic behaviors of twist-induced denaturation bubbles in a long, stretched random sequence of DNA. The small bubbles associated with weak twist are delocalized. Above a threshold torque, the bubbles of several tens of bases or larger become preferentially localized to AT-rich segments. In the localized regime, the bubbles exhibit "aging" and move around subdiffusively with continuously varying dynamic exponents. These properties are derived by using results of large-deviation theory together with scaling arguments and are verified by Monte Carlo simulations.
我们研究了在长而伸展的随机DNA序列中,扭曲诱导的变性气泡的热力学和动力学行为。与弱扭曲相关的小气泡是离域的。超过阈值扭矩后,几十个碱基或更大的气泡优先定位于富含AT的片段。在局部化区域,气泡表现出“老化”,并以连续变化的动力学指数进行亚扩散移动。这些性质是通过使用大偏差理论的结果以及标度论证推导出来的,并通过蒙特卡罗模拟得到验证。