From 2007.igem.org

Abstract　　Concept & Model　　Requirements　　Genetic_circuit　　Works　　About_our_team

Genetic Circuit

Fig1 is an outline of our genetic circuit, designed for realizing our Concept&Model.

All the cells (Wokers and Idlers) have the same genetic circuit. (Just as the 'society' members have practically the same genetic backgrounds)

Workers (State-A)

(Fig2) In the A-state cell, promoter Pa is "on", and the cell expresses repressor Ra, luxI, and RFP. Repressor Ra put the promoter Pb into "off", and prohibits to change the state. This cell also expresses luxI, which makes AHL (cell-cell communication molecule). And in the downstream of these genes, there is an RFP gene. So we can detect state A cell using FACS.

Idler (State-B)

(Fig3) In the B-state cell, with the exsistence of AHL, promoter Pb is "on". And repressor Rb and GFP are expressed. Repressor Rb inhibits the expression of promoter Pa, and GFP is used to detect state-B cells.

If Workers are removed...

(Fig 4)If A-state cells are removed, B-state cells recognizes the absense of A-cells. That is, they respond to the decrease of AHL, not to produce repressor Rb. In this condition, repressions of Pa by Rb, and Pb by Ra are declined. This puts the toggle-like circuit into "reset".