S u m m a r y :
A race horse movie has been encoded in DNA in living cells, and then replayed—thus has the new study, recently published in the journal Nature, brought into existence the ‘world’s first molecular recorder’.
Making a Molecular Recorder
DNA encodes genetic data—all about what makes you up, or so to say, the story of your (physical) life. Now, for the first time ever, an actual movie, albeit a primitive one, has been encoded in it, and to make matters even more interesting and unprecedented, this movie was quite accurately ‘RE-played’. A movie, a series of events occurring in sequences, recorded in DNA molecules means that someday, perhaps, we can make a molecular recorder by sequencing the genome of a developing cells to view its dynamic internal conditions.
The most wonderful feat has been achieved by a team of researchers from Harvard Medical School, Boston. Neuroscientist Seth Shipman says that their main aim is to transform cells into historians.
“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,” says Shipman.
Biological Cells Recording Their Own Show
Documenting sequential events into a movie down to the molecular level would revolutionise recording using molecular engineering, write the authors. Cells would be the main actors at play, or more appropriately, the cameramen: they would be induced to record molecular reactions happening in their own genomes. For instance, the changes—the movie—in gene expression would, thus, be recorded.
Using this information, researchers might understand how to engineer similar cells, explains Shipman. Furthermore, the steps recorded could be used to study disease and develop therapies.
Making the Movie Using Bacterial Defense Mechanism
Shipman and his colleagues wanted to show that DNA could encode data other than genetic information. They used gene editing technology CRISPR to encode, in DNA inserted into bacteria, an image depicting a human hand.
Why CRISPR? What is it, to begin with? CRISPR consists of proteins and DNA that constitute a defense system in some bacteria: responding to viral infections, the CRISPR in bacteria remove part of the viral DNA to store it in their own genome so that they are able to recognise (and combat) this virus in case it infects them again. This sequential characteristic of the CRISPR, thus, makes it ideal for the recording of events unfolding over time.
After the encoding of the image, the researchers demonstrated its retrieval. Thereafter, they encoded and reorganised a race horse in motion sequence of pictures (similar to moving pictures). Next step entailed the translation of 5 snaps of the horse in motion photo sequence into DNA. This frame of translated DNA was then sequentially fed to bacteria. The bacterial DNA was then sequenced to reconstruct the movie—this was successfully done, with an accuracy of 90%.
Means to an End: DNA Movie to Study Brain
The end goal of the researchers is to use this technique to study the brain.
“We want to use neurons to record a molecular history of the brain through development,” said Shipman. “Such a molecular recorder will allow us to eventually collect data from every cell in the brain at once, without the need to gain access, to observe the cells directly, or disrupt the system to extract genetic material or proteins.”