What If Cells Kept Receipts of Their Gene Expression?

The first and second genes were activated by the same chemical for 24 hours. In theory, we should turn on all the recording proteins at the same time, but only for the first half and the second half.

To double-check their work, they reversed the conditions and added the chemical. The Retro-Cascorder recorded the expression of both genes.

While other recording systems store information in DNA, the one made by Shipman's group has an additional degree of specificity. Timothy Lu is a synthetic Biologist at the Massachusetts Institute of Technology who was not involved in the study.

Harris Wang is a Biologist at Columbia University He says that the work pushes us into a new area of how we are able to glean information about the inner workings of the cell. Wang is curious to see if the recording systems can keep a record of the degree to which a gene is turned on or off. Epigenetic regulation can be used to change genes to be expressed at different levels rather than simply on or off.

Shipman and his team share Lu's interest in seeing this system implemented in a mammal. The long-term goal is to record complex events that occur over weeks and months in mammals. Scientists might be able to understand how different genes are turned on and off as Parkinson's progresses.

Scientists think the Retro-Cascorder could be used to turn a bacterium into a biosensor. Thesebacteria could be used to study the human gut. A lot of things that we would normally care about on a very sensitive level are affected by the actions ofbacteria. We can put them to work in a place that is difficult to monitor if we could just get them to store that information. The bacterium has a DNA receipt book that can be used to identify which compounds are present and when.

He is grateful that the order works. Cell parts can be jerry-rigged. He says evolution gets us to something useful and then we cherry-pick it.