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Paper Review #2

"Synthetic Gene Networks that Count"

Friedland, et al., 2009




This paper shows a clear, clean experimental design along with clear figures that demonstrate the data and the data compared to mathematical models. Because of the high modularity and temporal range of the two synthetic counter designs, their constructions seem to have the capacity for broad implications and applications. They demonstrate the ability of the two counter designs to enable the programming and generation of specific desired output expression levels of various protein species of interest up to three. The design of the counters, however, imply the ability to reach higher numbers, using different recombinases and polymerases. The novel cellular behavior programming that the paper discusses implies impressive applications in terms of medicine, biosensing, and bioremediation. Other applications include the analysis of sequential events and circuits. The broad applications of these synthetic circuits and models and the specificity these applications can have are very impressive and seem highly promising. I found the possible ability to specificaly program cell death particularly interesting, as it could apply to cancer treatment/therapy. I would have liked to have seen an example of a higher number counter, a different protein species of interest, and different recombinases and polymerases such a cascade would require. One must take into account the limited space for such articles, though, and a lot of interesting information appears in the supplemental information.





Friedland AE, Lu TK, Wang X, Shi D, Church G, and Collins JJ. Synthetic Gene Networks that Count. Science [Internet]. 2009 May 29 [cited 2011 April 20];324(5931): 1199-1202. Available from: 


*Note: All citable information was taken from this original paper.


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