However, research is increasingly showing that these so-called synonymous codons are not truly equal. Some codons make mRNA molecules more stable and easier for cells to translate into proteins, making them more efficient. Others, considered non-optimal, lead to weaker translation and are more likely to be broken down. Until now, scientists have not fully understood how human cells recognize and respond to these less efficient codons.

Scientists Search for the Cell’s “Quality Control” System

To investigate this question, a research team from Kyoto University and RIKEN, led by Osamu Takeuchi and Takuhiro Ito, carried out a series of experiments aimed at uncovering how cells handle codon efficiency.