Defining Thermodynamic and Structural Features of ROSE-like RNA Thermometer

Abstract

RNA thermometers (RNATs) are temperature-sensitive structural elements found in the 5′ untranslated regions (UTRs) of mRNAs that regulate translation in response to heat. Previous studies have characterized RNA thermometers across diverse bacterial systems to showcase how conformational changes in these structures expose the ribosome binding site (RBS) to modulate translation. To better understand this process, we focus on the thermodynamic and structural features of the ROSE-like class of RNA thermometers to define the parameters regulating their temperature responsiveness. We analyzed the average ΔG at different temperatures, base-pair content, and secondary structural motif features to establish trends that demonstrate how fluctuations in temperature influence changes in RNA secondary structure. Based on our analysis, weak hydrogen bonding from A–U/G•U-rich base pairing plays a significant role in thermal sensitivity. Additionally, our findings indicate that absolute thermodynamic stability, rather than ΔG shifts, plays a more decisive role in thermoregulation.