Part:BBa_K2913009

PfnrF8

This is a hypoxia-inducible promoter to restrict gene expression specifically in the hypoxic environment of tumors. The transcriptional activation promoted by the PfnrF8 needs a specific transcription factor called FNR, which can bind to oxygen. When the oxygen level is at a normal range in the internal environment, the transcription factor FNR will associate with oxygen, leading to its impeded binding to the PfnrF8 promoter, and reduce the transcription of its downstream gene. However, in the hypoxic environment of tumors, FNR will disassociate with oxygen and activate its downstream gene.

result

Written by iGEM19_NEFU_China

We use this part to feel the hypoxia environment in our case.

The series of concentrations of sodium sulfite (0, 0.25, 0.5, 0.75 and 1 g/l Na₂SO₃) can make hypoxia environment (Fig.a). Under the PfnrF8 promoter, the activity of lacZ can be seen to rise markedly from 0 g/l to 1 g/l Na₂SO₃ (Fig.b). This promoter can respond our hypoxia environment regularly.See more information on iGEM19_NEFU_China's Result PAGE

Fig.(a) Dissolved oxygen change curve under a series of concentrations of sodium sulfite (0, 0.25, 0.5, 0.75 and 1 g/l Na₂SO₃). Fig.(b) Hypoxic inductions of PfnrF8 promoter in E. coli Nissle 1917. Expression of lacZ shows the Na₂SO₃ concentration dependence in increasing sodium sulfite concentrations (0, 0.25, 0.5, 0.75 and 1g/l Na₂SO₃). β-gal activity was measured as above. Values are expressed as percentage of promoter activity at positive (The mutant of PfnrF8, with strong expressing and not induced by hypoxia).

References

[1] Ryan, R.M., et al., Bacterial delivery of a novel cytolysin to hypoxic areas of solid tumors. Gene Ther, 2009. 16(3): p. 329-39.

[2] Bell, A. and S. Busby, Location and orientation of an activating region in the Escherichia coli transcription factor, FNR. Mol Microbiol, 1994. 11(2): p. 383-90.

[3] Moser, F., et al., Dynamic control of endogenous metabolism with combinatorial logic circuits. Mol Syst Biol, 2018. 14(11): p. e8605.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal NheI site found at 21
  Illegal NheI site found at 44
  
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]