Composite

Part:BBa_K2244009

Designed by: Chen Hong   Group: iGEM17_SSTi-SZGD   (2017-10-25)
Revision as of 16:51, 25 October 2017 by Qiucheng (Talk | contribs)

ColE promoter+mCherry gene+T1 terminator+Constitutive promoter+Lev1 gene+T1terminator


The device is a functional plasmid containing a light repressor LEV1 (BBa_K2244005), which undergoes conformational change upon light irradiation and dimerized to bind regulatory sequence on ColE promoter (BBa_K2244006), thus inhibits target gene expression. While in darkness, dimerization does not occur thus gene expression proceeds. This device is a light repressing system with high induction efficiency and low leakage. mCherry ((BBa_K2244008)) is reporter gene used in this system to prove its function as well as help to characterize it. mCherry gene can be replaced by any gene sequence in light-regulated studies

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ColE promoter sequence is derived from the promoter region of colicin E gene located in the ColE1 plasmid of E.coli. ColE promoter contains a ‘SOS’ operator region that allows the binding of LexA protein to repress transcription. mCherry is a red fluorescent protein used as a reporter. It is based on a fluorescent protein that was originally isolated from Discosoma sp.mCherry sequence is codon optimized for E. coli expressionm and can be replaced by any gene sequence in light-regulated studies.

LEV1 repressor is a fusion protein of VVD and LexA, LexA repressor is a transcriptional repressor of SOS regulon in E.coli. It’s form chromosome of Escherichia coli str. K-12 substr. MG1655 (strain: K-12, substrain: MG1655) LexA autocleavage, stimulated by RecA, of the first 84 aa of LexA removes the DNA binding region and is required to activate the SOS response. LexA is a protein that belongs to the LexA family .

Blue light sensor VIVID was derived from the chromosome of Neurospora crassa. The LOV domain of the protein VVD has the capacity to self-dimerize upon light stimulation, Based on this property, the VVD LOV domain was fused with a smaller version of the Gal4 DNA binding domain and the p65 transactivation domain. A common feature of several blue light photoreceptors is the presence of LOV domains, which are able to bind a molecule of flavin mononucleotide (FMN) or flavin adenine dinucleotide (FAD) as chromophore, forming upon light stimulation a cysteinyl flavin C4a adduct.

T1 terminator is the most commonly used terminator in E. coli.


Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal NheI site found at 1015
    Illegal NheI site found at 1038
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal AgeI site found at 845
    Illegal AgeI site found at 1753
  • 1000
    COMPATIBLE WITH RFC[1000]


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Categories
Parameters
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