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Part:BBa_K4169030
Cre-reverse loxP system:working when you need to express genes in the other direction
In the presence of theophylline, expression of subsequent Cre recombinase is induced.In addition, the promoter and RBS between the two loxP will be flipped, making it express genes in the other direction.
Usage and Biology
When our engineered bacteria sense theophylline, it expresses Cre, which recognizes the reverse repeat sequence at both ends of the loxP site and binds to form a dimer, which then binds to a dimer at another loxP site to form a tetramer. In this way, Cre mediates sequence flips between reverse loxPs.
Functional Parameters
To verify the functionality of our part, we had the upstream gene of the promoter replaced with red fluorescence,and then transferred our plasmid into Escherichia coli DH5α and measured the intensity of red fluorescence with a microplate reader. Unfortunately, our bacteria did not produce red fluorescence, and upon analysis, it was conjectured that the transcriptional loxP formed a strong secondary structure and could not translate the red fluorescence protein behind it.
Sequence and Features
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12INCOMPATIBLE WITH RFC[12]Illegal NheI site found at 7
Illegal NheI site found at 30
Illegal NheI site found at 1292
Illegal NheI site found at 1315 - 21INCOMPATIBLE WITH RFC[21]Illegal BamHI site found at 454
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal AgeI site found at 39
Illegal AgeI site found at 140 - 1000COMPATIBLE WITH RFC[1000]
None |