Types | DnaRegion
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Roles | engineered_region
Composite
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Description
This is an oscillator that is based on the self-regulation of LacI. pLac is initially on, which causes LacI to be expressed. The LacI then binds to the pLac promoter, shutting it down. After LacI degrades, the pLac promoter is then naturally turned on, thus expressing LacI once again. This cycle continues, causing oscillations to occur. The oscillations of LacI in turn regulate the oscillations of pLac+TetR/RFP, which again regulate the oscillations of pTet+GFP. This oscillator can be used to oscillate proteins.
There are numerous benefits that this oscillator embodies:
BENEFITS OF THE TWO COMPONENT OSCILLATOR
This two component oscillatory design has numerous benefits, which are not included in the three component repressilator:
1. Only one promoter is used, so promoter strength differences do not dampen oscillation.
2. Only one repressor is used, so repressor half-life differences do dampen oscillation.
3. The oscillator can be tuned using Isopropyl-beta-D-Thiogalactopyranoside (IPTG), which prevents LacI from binding to pLac and hence maximizes pLac activity.
Notes
The TetR/RFP and GFP allows for physical observation of the oscillatory peaks and troughs. IPTG can be used to tune the oscillator. Promoter strength differences and repressor half-life differences do not dampen oscillation.
Source
This part was made using the BioBrick parts from the 2013 Spring Distribution kit.