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Model for Folding and Aggregation in RNA Secondary Structures

Vishwesha Guttal·Ralf Bundschuh
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Abstract

We study the statistical mechanics of RNA secondary structures designed to have an attraction between two different types of structures as a model system for heteropolymer aggregation. The competition between the branching entropy of the secondary structure and the energy gained by pairing drives the RNA to undergo a `temperature independent' second order phase transition from a molten to an aggregated phase'. The aggregated phase thus obtained has a macroscopically large number of contacts between different RNAs. The partition function scaling exponent for this phase is θ~ 1/2 and the crossover exponent of the phase transition is ν~ 5/3. The relevance of these calculations to the aggregation of biological molecules is discussed.

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Vishwesha Guttal, Ralf Bundschuh. 2006-01-12. Model for Folding and Aggregation in RNA Secondary Structures. https://doi.org/10.1103/physrevlett.96.018105

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