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bioRxiv · 10.1101/2024.03.22.586224

Universal Cold RNA Phase Transitions

Rissone, P.·Severino, A.·Pastor del Campo, I.·Ritort Farran, F.
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Abstract

RNAs diversity of structures and functions impacts all life forms since primordia. We use calorimetric force spectroscopy to investigate RNA folding landscapes in previously unexplored low-temperature conditions. We find that Watson-Crick RNA hairpins, the most basic secondary structure elements, undergo a glass-like transition below TG [~] 20{degrees}C where the heat capacity abruptly changes and the RNA folds into a diversity of misfolded structures. We hypothesize that an altered RNA biochemistry, determined by sequence-independent ribose-water interactions, outweighs sequence-dependent base pairing. The ubiquitous ribose-water interactions lead to universal RNA phase transitions below TG, such as maximum stability at TS [~] 5{degrees}C where water density is maximum, and cold denaturation at TC [~] -50{degrees}C. RNA cold biochemistry may have a profound impact on RNA function and evolution.

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Rissone, P., Severino, A., Pastor del Campo, I., Ritort Farran, F.. 2024-03-25. Universal Cold RNA Phase Transitions. https://doi.org/10.1101/2024.03.22.586224

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