Part:BBa_K174003

Heritable, Tunable, Stochastic Switch

This tunable switch is biased heads or tails. It can be tuned to control cell differention and fate stochastically.

As an indication of the decision, either Rfp on the left side of the switch or the downstream genes on the right side of the switch is expressed. An invertible region including sigA promoter and Hin CDS is inverted by Hin [1,2,3]. The expression of Hin can be controlled by IPTG and Xylose. As a third level control, with the modified version of ssrA tag on the C-terminus of the Hin protein, it can quickly be degraded (See Part:BBa_K174002 for arabinose controlled SspB adaptor protein for the degradation).

Expresion of Hin, hence the orientiation of the invertible region is affected by the concentration of IPTG, Xylose, Arabinose, the binding affinity of these inducers to LacI, XlyR, AraR respectively, these proteins' repression coefficients on pspac, xylA and araE promoters and the promoters' strengths.

Downstream genes on the left and right sides of the switch can be used to trigger cell fate decisions. Rather than synthesising the switch with Gfp, our switch was cloned into pGFP-rrnB[4] integration vector on NheI site and ended up with Gfp on the right side. However it was sent to the registry in pSB1AT3 since the pGFP-rrnB is not a Biobrick compatible vector.

For more information about this part go to Newcastle iGEM2009 [http://2009.igem.org/Team:Newcastle/Stochasticity Stochasticity] and [http://2009.igem.org/Team:Newcastle/Modelling Modelling] pages.

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 1791
  Illegal AgeI site found at 105
  Illegal AgeI site found at 217
  
• 1000
  COMPATIBLE WITH RFC[1000]

References

1. Ham, T.S., et al., Design and Construction of a Double Inversion Recombination Switch for Heritable Sequential Genetic Memory. PLoS ONE, 2008. 3(7): p. e2815.
2. Haynes, K., M. Broderick, et al. (2008). "Engineering bacteria to solve the Burnt Pancake Problem." Journal of Biological Engineering 2(1): 8.
3. Kutsukake, K., et al., Two DNA Invertases Contribute to Flagellar Phase Variation in Salmonella enterica Serovar Typhimurium Strain LT2. J. Bacteriol., 2006. 188(3): p. 950-957.
4. Veening, J.-W., H. Murray, and J. Errington, A mechanism for cell cycle regulation of sporulation initiation in Bacillus subtilis. Genes & Development, 2009. 23(16): p. 1959-1970.