Living species’ genes encode their complexity, but where do these genes come from? The University of Helsinki researchers have found answers to this long-standing question, shedding light on the formation of tiny regulatory genes. They have outlined a method that generates DNA palindromes which, under the right conditions, can evolve into microRNA genes.
MicroRNAs are small molecules that play a crucial role in coordinating the actions of genes. While the number of genes in a species remains relatively constant, new genes can emerge during evolution, sparking fascination among scientists. The origin of these new genes has remained a mystery until now.
Researchers at the Institute of Biotechnology at the University of Helsinki have discovered a mechanism that can generate complete DNA palindromes, leading to the creation of new microRNA genes from previously noncoding DNA sequences. The team compared DNA replication to typing on a keyboard, with DNA being copied one base at a time. They found that certain replication errors could create larger errors, such as copy-pasting text from another context, resulting in the formation of palindromic sequences.
These palindromic runs are crucial for the functioning of RNA molecules, facilitating the folding of the microRNA genes into a hairpin structure. The researchers focused on microRNA genes due to their simple structure and found that whole palindromes could be created by single mutation events during the evolutionary process.
By studying humans and other primates, the researchers demonstrated that this mechanism could explain at least a quarter of the novel microRNA genes. They believe that the results can be generalized to other RNA genes and molecules, suggesting the potential for the emergence of new genes and their impact on human health.
The study, published in the Proceedings of the National Academy of Sciences (PNAS), provides an elegant model for understanding the evolution of RNA genes. It also has broader implications for understanding the fundamental principles of biological life.
With this groundbreaking research, the University of Helsinki researchers have unlocked some of the mysteries surrounding gene formation and provided valuable insights into the origin of new genes. Their findings may have significant implications for our understanding of evolution and the complex mechanisms of life.
