Cells in a population can have varied responses to a stimulus but are able to coordinate their responses through communication motifs. Chemical signaling to neighbors in a community can allow populations to make more robust and effective decisions as a collective whole. T cells, for instance, need to know whether or not to proliferate to attack a given antigen. If too many proliferate, an autoimmune disorder is generated. If too few proliferate, the antigen continues to attack the body. By sensing the antigen at varying levels and communicating with the population, each T cell knows whether or not it should activate and what level to activate at, in order to carry on their function properly.

Nevertheless, how do these cells communicate and how do they understand their role as part of the collective? How do these genetically identical cells in the same population differentiate themselves from others? What motifs are necessary to elicit a bimodal response, in which high activating cells stay ON and low activating cells stay OFF? Our goal this year is to understand these questions and to take advantage of the natural variation found within cells of the same population in order to amplify that difference and create two divergent responses.

Our genetic circuit will utilize a stimulus that activates a fluorescent readout for individual response (GFP) and the secretion of a communication signal that is sensed and secreted by all members of the community. This community signal will in turn activate a fluorescent readout for community response (RFP).

General Circuit Diagram


Basic Circuit Button Sense Circuit Button Degradation Circuit Button Hotspots Circuit Button Hotspots Circuit Button Synthetic Circuit Diagram

Click on the part of our circuit you are interested in learning about in the image above.


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