Genomically Encoded Memory

Applications

This technology is a method of encoding cellular memory through DNA editing and has potential applications in cellular or environmental sensing.

Problem Addressed

Electronic sensor devices are limited by size and energy requirements. Cells are intrinsically able to sense their surroundings, operate close to the physical limits of energy consumption, and hold large amounts of data stably in the form of DNA. These cellular characteristics have led engineers to propose cells as nanoscale computing devices. However, using cells to stably store data requires cellular circuitry to make changes to the DNA sequence of the cells. These inventors have engineered cellular circuitry to encode memory of cellular signals in DNA.

Technology

The endonuclease Cas9 allows site-specific double stranded cutting of DNA directed by sequence-specific guide RNAs. This technology puts Cas9 and guide RNAs under the control of inducible promoters controlled by extracellular or intracellular signals. When that signal, or combination of signals, is sensed the guide RNAs direct Cas9 to a target sequence, where a double stranded cut is made in the DNA. Mutations are induced at the site of the double stranded cut as the cell attempts to repair the break. This DNA editing in response to an input signal results in long-term recording in the cell and its progeny, and the signal memory can be ready by harvesting cells and sequencing the target loci. This technology could be used to record the events happening within an individual cell. Alternatively, this technology could be used as a way of cheaply distributing many environmental sensors over large areas of land or water.

Advantages

  • Cellular memory recorded in DNA
  • Recording of intracellular or extracellular events through choice of inducible promoter