RNA from the origins of life to today’s lives
The origin of life is almost impossible to track. Chemical conditions on early earth were harsh and complex and are very difficult to reconstruct. Thus, it is challenging to understand how a system of biomolecules that supports Darwinian evolution could evolve out of organic molecules of prebiotic origin. In recent years, theoretical and experimental chemistry combined with analysis of extreme chemical environments on earth and on extraterrestrial missions have helped our understanding of early life’s chemistry.
Today, we assume that the earliest moment in molecular evolution that allowed for heredity is represented by an “RNA world”. This term describes a scenario, where the genetic information was passed on in the form of RNA, which also acted as the key catalyst. Nowadays, RNA has lost the function of information storage to DNA and the function of catalysis to proteins. Nevertheless, it is still critical for all cellular functions. It acts on multiple steps in the translation of DNA sequences into proteins. Furthermore, RNA can act as a ribozyme and through a plethora of small and long non-coding RNA (ncRNA) regulates gene expression and protein translation.
Thus, it is not surprising that RNA has reentered the central stage of biomedical research in recent years. The use of small interfering RNA has revolutionized experimental research and drug discovery allowing for genome-wide screens for virtually every cellular process. New classes of ncRNA have opened new avenues for our understanding of gene regulation and may provide new mechanisms and targets for medical interventions. Therefore, RNA research is experiencing an extremely exciting period of new discoveries that will not only change our view about how life came to place but may also affect our daily lives in the future.