The Impact of RNA Folding at Low Temperatures on the Evolution of Life

Ribonucleic acid (RNA) is a crucial biological molecule that plays an essential role in the genetics of organisms and the evolution of life on Earth. A recent study published in the Proceedings of the National Academy of Sciences sheds light on how the process of RNA folding at low temperatures can offer new insights into primordial biochemistry and the development of life on our planet.

RNA is composed of ribose, a monosaccharide, and phosphate groups linked to four nitrogenous bases: adenine (A), guanine (G), cytosine (C), and uracil (U). The sequence of bases and the three-dimensional structure of RNA are critical determinants of its biological functions and versatility. Understanding how RNA molecules fold in on themselves is essential for decoding their functions and mechanisms.

The study conducted by Professor Fèlix Ritort and his team at the University of Barcelona reveals that RNA sequences forming hairpin structures adopt new compact configurations at temperatures below 20°C. These novel structures are a result of ribose-water interactions, with RNA stability peaking at +5°C due to the maximal density of water. This phenomenon of RNA stability is influenced by environmental factors such as salt concentration and acidity levels.

The researchers hypothesize that the temperature range for RNA stability observed in the study is universal and applicable to all RNA molecules. The formation of hydrogen bonds between ribose and water plays a significant role in stabilizing RNA structures at low temperatures. This altered biochemistry challenges traditional assumptions about RNA stability based on base pairing rules.

The study suggests the existence of a primitive biochemistry termed the “sweet-RNA world,” characterized by ribose-water interactions that predate known base pairing mechanisms in RNA. This primitive biochemistry may have originated in cold environments on Earth and in outer space, on celestial bodies exposed to extreme temperature fluctuations.

The research on RNA folding at low temperatures opens up new avenues for understanding the evolution of life and the role of RNA in primordial biochemistry. The discovery of novel RNA structures and the impact of ribose-water interactions provide valuable insights into the origins of life on Earth and the potential for life elsewhere in the universe. Further studies in this field could uncover additional secrets of RNA folding and its implications for the development of life forms.