Lipid membranes modulate the activity of RNA through sequence-specific interactions

Czerniak, T.; Saenz, J. P.

doi:10.1101/2021.03.25.437010

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bioRxiv · 10.1101/2021.03.25.437010

Lipid membranes modulate the activity of RNA through sequence-specific interactions

Czerniak, T.·Saenz, J. P.

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Abstract

RNA is a ubiquitous biomolecule that can serve as both catalyst and information carrier. Understanding how RNA bioactivity is controlled is crucial for elucidating its physiological roles and potential applications in synthetic biology. Here we show that lipid membranes can act as RNA organization platforms, introducing a novel mechanism for ribo-regulation. The activity of R3C ribozyme can be modified by the presence of lipid membranes, with direct RNA-lipid interactions dependent on RNA nucleotide content, base pairing and length. In particular, the presence of guanine in short RNAs is crucial for RNA-lipid interactions, and G-quadruplex formation further promotes lipid binding. Lastly, by artificially modifying the R3C substrate sequence to enhance membrane binding we generated a lipid-sensitive ribozyme reaction with riboswitch-like behavior. These findings introduce RNA-lipid interactions as a tool for developing synthetic riboswitches and novel RNA-based lipid biosensors, and bear significant implications for RNA World scenarios for the origin of life.

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Czerniak, T., Saenz, J. P.. 2021-03-25. Lipid membranes modulate the activity of RNA through sequence-specific interactions. https://doi.org/10.1101/2021.03.25.437010

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