Difference between revisions of "Part:BBa K2066122"

Latest revision as of 05:27, 29 October 2016

Synthetic Enhancer Project: 3X TetO Binding Cassette(52S) + NRII + TetR + sfGFP on UNS

The synthetic enhancer, first characterized by Amit et. al. 2011, allows for a multistate transfer function by modulating the rigidity of the spacer region between the enhancer promoter region, thus affecting the DNA rigidity and hence the kinetic capability of the two components to loop together and initiate transcription. For more information on the mechanism, please refer to: http://2016.igem.org/Team:William_and_Mary/Synthetic_Enhancer.

This part takes the synthetic enhancer circuit with a three TetO binding cassette as, the promoter and coding region of NRII from the helper plasmid of Amit et. al. 2011 circuits as well as constitutively expressed TetR (Bba_I739001) and puts it onto a single BioBrick backbone flanked by the UNS regions. This part allows for a four step output response due to the three TetO binding cassette in the spacer region between the enhancer and promoter. Combining NRII, TetR, and the synthetic enhancer circuit reduces metabolic strain, decouples the system from LacI/IPTG dependence, and allows for an ease of cloning due to the UNS sequences. The number of filled TetO sites influences the rigidity and the thermodynamics of the looping. Furthermore, we included an sfGFP reporter for more pronounced fluorescent signals.

aTc induction should be used to obtain a multistate response curve.

Source: The enhancer, tet cassette, glnAp2 synthetic promoter, and NRI coding region sequences were derived from the synthetic enhancer circuits from Amit, R., Garcia, H. G., Phillips, R. & Fraser, S. E. Building enhancers from the ground up: a synthetic biology approach. Cell146, 105–118 (2011). The NRII2302 coding region and the promoter that it is controlled by is derived from the helper plasmid pACT tet from Amit et. al 2011. The sequence for the TetR controlled by J23105 promoter is from Biobrick part Bba_I739001. The TetR is inserted between the UNS2 sequence and is added to the same plasmid as the synthetic enhancer suite and NRII2302 to reduce the interference with other genetic circuitry in the bacteria and thus decrease overall metabolic strain. The sfGFP flourescent reporter design is inspired by C. Lou, B. Stanton, Y.-J. Chen, B. Munsky, C. A. Voigt, Ribozyme-based insulator parts buffer synthetic circuits from genetic context. Nat. Biotechnol. 30, 1137 (2012). doi:10.1038/nbt.2401 pmid:23034349. The UNS sequences at the ends of the insert are derived from Torella, J. P., Boehm, C. R., Lienert, F., Chen, J. H., Way, J. C., & Silver, P. A. (2013). Rapid construction of insulated genetic circuits via synthetic sequence-guided isothermal assembly. Nucleic acids research, gkt860. A huge thanks to all the researchers involved in its original creation!

Sequence and Features