The market of recording devices may undergo a significant change in the nearest future. Scientists have used CRISPS-Cas9 - a popular tool for gene-editing - and transformed the DNA of a cell in a way enabling it to record both the duration and sequence of events occuring within the cell.
Many similar CRISPR-based recorders have appeared there in the recent years. Hopefully, the global-scale use of inventions of this kind will take place in the future to enable tracing the individual lineage of a cell or changes in gene expression.
"The recording capacity of the genome is tremendous. Thanks to CRISPS, we finally have a tool enabling us to use these capabilities", says Jan Philipp Junker, a biologist at Max Delbrück Center for Molecular Medicine in Berlin.
The inspiration to create the cellular recorder has turned out to be trivial. It was provided by the flight data recorder that can be found on each aircraft. Similarly to how the device monitors the data collected by the aircraft, the biological recorder is capable of "recording" stimuli that the cell is subject to, or even erase the information previously collected to record the new one anew and within the same genome.
The CRISPR-Cas9 method used for changing the DNA sequence relies on the use of Cas9 enzyme in order to cut a fragment of the DNA. The inventors of the biological recorder have used plasmids, also creating the bacterium capable of expressing Cas9 in the presence of a specific antibiotic. The entire system was named CAMERA1. Bacterial cells are not equipped in certain repair mechanisms that are present within mammalian cells - therefore, the plasmid being a target of Cas9 would previously be subject to degradation after which a new one was supposed to take its place. Scientists could read out the information on the basis of measurements of the ratio of degraded plasmids to normal ones, thus reflecting the processes occuring within the cell. After its refinement, the invention is to serve the tracking of a developmental path of individual cells of the zebrafish.