Sensor Project

From 2011.igem.org

(Difference between revisions)
Line 3: Line 3:
<center>
<center>
[[RecA Project]]
[[RecA Project]]
-
[[Reporter Project]]
 
[[Sensor Project]]
[[Sensor Project]]
 +
[[Reporter Project]]
</center>
</center>

Revision as of 17:48, 13 September 2011

RecA Project Sensor Project Reporter Project

The Sensor

The design of our sensor was based on the lambda phage lysogenic vs lytic switch. Optimally, the system would be activated in the presence of DNA damage due to radiation. For that reason, we utilized the lambda phage switch, which transitions from the lysogenic cycle to the lytic cycle when DNA damage is detected. The genetic circuit we designed focuses on the DNA damage-sensitive lambda phage lytic-lysogenic cycle switch followed by a rapid response reporter similar to the immobilized fusion enzyme system pioneered by the Imperial College of London 2010 iGEM team. An initial design of our sensor circuit is illustrated below.


Sensor1.jpg


Under normal conditions, PRM is active, which transcribes the lambda repressor, cI + RBS. The lambda repressor binds to OR1 and OR2, repressing PR, which in turn inhibits the transcribtion of Cro and TEV.

Sensor2.jpg

Once DNA damaged occurs, the ssDNA binds to RecA. RecA becomes activated and cleaves the cI repressor, allowing for PR to turn on. Cro then binds to OR3, which represses PRM and inhibits the transcription of the cI repressor. Now that PR is active, the transcription of the TEV protease occurs, which is used in the reporter structure of the circuit.