Part:BBa_K4242003

FleN gene

This part sequence originated from Pseudomonas aeruginosa encodes FleN protein. FleN is an important synergistic protein working with FleQ protein, FleN alone does not bind to DNA but FleQ and FleN interact in a FleQ/FleN/DNA complex. FleN stimulates the bending of pel promoter DNA when FleQ and ATP or ADP are present. The DNA bending stimulated by FleN occurs only when ATP is present and disappears when c-di-GMP is added[1].

Usage and Biology

fleN plays an important role in P.aeruginosa, which exhibits antagonistic activity against FleQ. FleN and c-di-GMP cooperate to inhibit FleQ activity and, by extension, flagella synthesis in P. aeruginosa. FleN is a significant synergistic protein to work with FleQ. What’s more, In the presence of ATP, FleN forms dimers inducing a bending of the pelA promoter by bridging the bound FleQ proteins[1]. In this situation, we can use c-di-GMP to regulate DNA bending caused by FleN and FleQ cooperation to control flagella biosynthesis genes and exopolysaccharide genes[2]. We can use this function to explore medicine research.

FleN protein assist FleQ protein bend with DNA

* Baraquet C et al. Nucleic Acids Res, 2012. Figure 1: Model of pel regulation. FleQ binds to two FleQ boxes on the pel promoter (A). FleQ interacts with FleN in the absence of ATP (B) as well as in the presence of ATP, but in this case it induces adistortion of pel DNA (C). We propose that FleN forms a bridge between two FleQ bound to their binding sites. The binding of FleQ to FleQ box 2 is essential for repression. The binding of c-di-GMP to FleQ induces a conformational change of FleQ, probably propagated through FleN, which induces the relief of pel distortion and leads to pel expression (D). The binding of FleQ to FleQ box 1 is essential for activation[1].

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal NgoMIV site found at 765
  
• 1000
  COMPATIBLE WITH RFC[1000]

References

[1]Baraquet C, Harwood CS. Cyclic diguanosine monophosphate represses bacterial flagella synthesis by interacting with the Walker A motif of the enhancer-binding protein FleQ. Proc Natl Acad Sci U S A. 2013 Nov 12;110(46):18478-83.

[2]Baraquet C, Murakami K, Parsek MR, Harwood CS. The FleQ protein from Pseudomonas aeruginosa functions as both a repressor and an activator to control gene expression from the pel operon promoter in response to c-di-GMP. Nucleic Acids Res. 2012 Aug;40(15):7207-18.