Short film recorded in bacterial DNA
Image credit: Harvard Medical School
Scientists at Harvard Medical School have successfully encoded a short film into the DNA of living cells, and replayed it with 90 per cent accuracy. They hope this could allow for the comprehensive study of neurological development and modelling of disease.
“We want to turn cells into historians,” said Dr Seth Shipman, a neuroscientist at Harvard Medical School, Boston. “We envision a biological memory system that’s much smaller and more versatile than today’s technologies, which will track many events non-intrusively over time.”
Dr Shipman and his colleagues had previously made use of CRISPR technology – which allows for cheap, precise and permanent DNA editing – in order to store sequences of DNA in bacteria. By encoding an image of a human hand in bacterial DNA, they were able to demonstrate that a genome is not capable of storing only genetic information, but general sequences of information too. The images are recorded in the cell as a ‘memory’ in order to prepare for a future ‘invasion’.
“The sequential nature of CRISPR makes it an appealing system for recording events over time,” said Dr Shipman.
Having successfully stored a still image in the DNA, the researchers went on to encode and reconstruct a sequence of five frames – pixel by pixel – taken from Eadweard Muybridge’s famous 1878 ‘race horse’ series of photographs using E. coli bacteria.
By sequencing the DNA, they were able to reconstruct the short film with 90 per cent accuracy.
The ability to record events in a sequence – like frames of a film – at a molecular level could reinvent the concept of recording in molecular engineering by allowing cells to record molecular events in their own genomes, the researchers suggest in their Nature report. This ‘Molecular Recorder’ could allow investigators to study, for instance, changes in gene expression by simply sequencing the genomes of the cells.
In particular, the researchers hope to be able to use their technique to study the ‘molecular history of the brain’, collecting read-outs on the changing internal state of neurons and other cells without the need to observe the cells directly, which is a highly disruptive and time-consuming process.