Loop Entropy Assists Tertiary Order: Loopy Stabilization of Stacking Motifs
نویسنده
چکیده
The free energy of an RNA fold is a combination of favorable base pairing and stacking interactions competing with entropic costs of forming loops. Here we show how loop entropy, surprisingly, can promote tertiary order. A general formula for the free energy of forming multibranch and other RNA loops is derived with a polymer-physics based theory. We also derive a formula for the free energy of coaxial stacking in the context of a loop. Simulations support the analytic formulas. The effects of stacking of unpaired bases are also studied with simulations.
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عنوان ژورنال:
دوره 13 شماره
صفحات -
تاریخ انتشار 2011