The iGEM Valencia Lighting Cell Display (iLCD) is our project for the present iGEM competition. We are developing BioElectronics, a combination of Electronics and Biology. We hereby prove that cell behaviour is controlled by electrical pulses. In order to demonstrate this, we are making a “bio-screen” of voltage-activated cells, where every “cellular pixel” produces light. It is just like a bacterial photographic system, but it's digital. Within seconds, instead of hours, you can get an image formed of living cells.
It is known that for instance neurons, cardiomyocites or muscle cells are able to sense and respond to electrical signals. These cells use a common second messenger system, calcium ion, which promotes a defined response when an electrical pulse is supplied to them. Nevertheless, these cultures present several disadvantages in order to use them from the technological point of view:
- Get easily contaminated.
- Genetic manipulation is complicated and expensive.
- To be very sensible to external conditions.
Valencia Team uses this electricity sensibility of calcium channel to produce yeast luminescence as a response to electrical estimulous. This project constitutes the FIRST TIME in which the electrical response of Saccharomyces and its potential applications have been tested building the first LEC (Light Emitting Cell). The obtained device will be used to build the first iLCD in history.
Therefore, the project is divided in several stages from the fabrication of the first LEC up to the cooperative integration of various LECs in the first iLCD. The global scheme of the project is summarized in the following scheme:
Three main parts can be appreciated:
- LEC Construction.
- LEC Characterization.
- iLCD: LEC Integration Device.
The main advantages of using electrical signals instead of chemical stimulation, as in the Coliroid project (Levskaya et al, Synthetic biology: Engineering Escherichia coli to see light. Nature 438, 441-442), are reversibility and high frequency: the system goes back to the resting state and it take seconds (down to 12 seconds) to refresh an image, actually showing animated pictures!. For that reason, we chose the calcium signaling because it is the fastest known modality of signaling in biology, and will allow for a fast refreshing rate of the screen.
iLCD will be a major advance in Synthetic Biology, opening the field of BioElectronics, integrating electrical signals with cell behaviours. This will reduce the response time of the cells to the activation signal by up to two orders of magnitude, as well as foster the combination of Electronics and Biology. Thus, our engineered yeast are a state-of-art bioelectronic device.