A memory for cells: ETH method shows which genes were active days earlier
Researchers at ETH Zurich get human cells to archive RNA molecules. This makes it possible to read out days later how a cell responded – for cancer research, for example. Study in Nature Biotechnology.
Archive image · Photo: Alessandro Della Bella / Wikimedia Commons, CC BY-SA 4.0 (cropped and resized)
Measuring a cell's gene activity normally gives only a snapshot. A team led by Randall Platt at ETH Zurich's Department of Biosystems Science and Engineering in Basel has developed a method in which human cells archive their RNA molecules over several days – making it possible to reconstruct afterwards which genes were active earlier. The study, “Recordanelles for transcriptome-wide single-cell RNA recording in human cells”, was published on 21 October in Nature Biotechnology.
The system consists of three optimised proteins, one of them derived from a stress granule protein. Their blueprints are introduced into the cells via plasmids, and the cells then build the archive themselves. It gathers RNA in a film around the mitochondria, where it is protected from degrading enzymes. Several thousand RNA molecules can be stored per cell. In cell cultures, the researchers showed how human cells respond to an immune signalling molecule.
“If you measure too late with the conventional method, you no longer see that the response has even taken place,” says co-first author Marcos Manero Carranza. The researchers have applied for a patent. Next, the technology is to be developed further for animal and cancer research – for example to study tumour cells that survive chemotherapy.