Testing Models For DNA Elasticity on Short Length Scales by Simulating DNA Supercoiling under Tension
نویسندگان
چکیده
منابع مشابه
Probing the elasticity of DNA on short length scales by modeling supercoiling under tension.
The wormlike-chain (WLC) model is widely used to describe the energetics of DNA bending. Motivated by recent experiments, alternative, so-called subelastic chain models were proposed that predict a lower elastic energy of highly bent DNA conformations. Until now, no unambiguous verification of these models has been obtained because probing the elasticity of DNA on short length scales remains ch...
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Protein-mediated DNA looping is ubiquitous in chromatin organization and gene regulation, but to what extent supercoiling or nucleoid associated proteins promote looping is poorly understood. Using the lac repressor (LacI), a paradigmatic loop-mediating protein, we measured LacI-induced looping as a function of either supercoiling or the concentration of the HU protein, an abundant nucleoid pro...
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2012
ISSN: 0006-3495
DOI: 10.1016/j.bpj.2011.11.1517