Researchers at the Centre for Genomic Regulation (CRG) in Barcelona have developed a technique that analyses only the transfer RNAs (tRNAs) actively engaged in protein production on ribosomes. The method, described in „Nature Methods,“ could accelerate the development of a new class of medicines for genetic diseases (DOI: 10.1038/s41592-026-03277-6).
Cells hold millions of tRNAs, small molecules that read the genetic code three letters at a time and deliver matching amino acids to the ribosome, the cell’s protein-making machinery. Until now, scientists studied them by measuring all tRNAs in a cell at once, assuming this gave a fair picture of those actually doing the job. The new work shows that the tRNAs at work can differ from the cell’s overall stock, particularly under stress.
„The field has largely assumed that sequencing all the tRNAs in a cell gives a good picture of the ones working in protein production. Our work shows that this is not necessarily the case, particularly under stress,“ said Mie Monti, the study’s first author. When cells were starved of leucine, one of the building blocks of protein, the team saw tRNAs piling up on the ribosome, whereas the expectation would have been for them to disappear entirely.
The results suggest some changes inside cells may have gone unnoticed, including in cancer cells, which are known to use tRNAs differently from healthy cells but had only been studied by counting every tRNA. The approach could also show which tRNA molecule a virus relies on during infection, potentially pointing to new ways of blocking it.
According to the authors, the biggest implication is that the method might accelerate development of medicines for genetic diseases. About one in 10 genetic errors known to cause inherited disease are typos that tell the cell to stop making a protein too early. Specially designed tRNAs can read past the false stop sign and restore the full protein without changing a patient’s DNA. Experimental tRNA medicines have already restored missing proteins in cells and mice in studies of cystic fibrosis and Duchenne muscular dystrophy, and one was cleared this year for its first trial in people.
„A single tRNA medicine could, in principle, be used to treat multiple unrelated rare diseases. This would be transformative for rare disease patients, as these groups are otherwise too fragmented for conventional drug development,“ said ICREA Research Professor Eva Novoa, who led the study. The method could also help those designing such medicines. „One thing is to design a tRNA that works in a test tube. Another is to know that it will actually go to the ribosome in sufficient amounts to be used by the cell,“ Monti explained.
The authors expect their method, called tRIBO-seq, to become a routine tool for finding the most promising candidate medicines. It was co-developed with the Italian company IMMAGINA Biotechnology. The technique works by isolating ribosomes busy making proteins and then reading the tRNAs inside one by one, showing which are in use, which chemical tags they carry and whether any are damaged, all in a single experiment. Conventional methods require about a week of growing cells and specialist equipment; the CRG method needs a single dish of cells and about a day and a half.
