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arXiv · 1810.02633

Cold denaturation of RNA secondary structures with loop entropy and quenched disorder

Flavio Iannelli·Yevgeni Mamasakhlisov·Roland R. Netz
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Abstract

We study the folding of RNA secondary structures with quenched sequence randomness by means of the constrained annealing method. A thermodynamic phase transition is induced by including the conformational weight of loop structures. In addition to the expected melting at high temperature, a cold melting transition appears. Our results suggest that the cold denaturation of RNA found experimentally is, in fact, a continuous phase transition triggered by quenched sequence disorder. We calculate both hot and cold melting critical temperatures for the competing energy scenario between favorable and unfavorable base pairs and present a phase diagram as a function of the loop exponent and temperature.

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Flavio Iannelli, Yevgeni Mamasakhlisov, Roland R. Netz. 2018-10-05. Cold denaturation of RNA secondary structures with loop entropy and quenched disorder. https://doi.org/10.1103/physreve.101.012502

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