Minnesota/24 June 2009

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Patrick
After discovering the error in the program I wished to submit many of the same programs to try and get back up to speed. First was smad_base which was the simple base model. smad_k2u/d changed the kinetic constant for the release of tetO1 by the tetR2:tetO1:2aTc complex (reaction 20, normally k = 100000 1/s). smad_k1u/d changed the kinetic constant for the release of tetO1 by the tetR2:tetO1:aTc complex (reaction 18, normally k = 1 1/s). smad_k12u/d did both at the same time. The results are expected tomorrow.

Ben
Since there are several problems with the first TNN model, we are deciding to focus on them one at a time. The first thing to work on is the leakiness problem. In order to deal with this issue, we are including a reaction that allows for the binding of the RNA polymerase to the operator site even if the site is occupied by a tetR. This will allow for some expression at an aTc concentration of 0, because at this point tetR is almost always bound to the tetO operator.

Here is the model we are working on:

Reaction Forward Kinetic Constant Reverse Kinetic Constant
RNAp + lacP + lacI4:lacO1 -> RNAp:lacP6.23E+05
RNAp + lacP + lacO1 ↔ RNAp:lacP1E+07 1
RNA:lacP -> RNAp:lacP* .01
RNAp:lacP* -> lacP + lacO1 + RNAp:DNAgfp30
RNAp:DNAgfp -> RNAp + gfp_mRNA30
gfp_mRNA + rib -> rib:gfp_mRNA100000
rib:gfp_mRNA -> rib:gfp_mRNA_1 + gfp_mRNA33
rib:gfp_mRNA_1 -> rib + gfp33
tetR2 + aTc ↔ tetR2:aTc2E+094E-04
tetR2:aTc + aTc ↔ tetR2:aTc21E+081E-03
tetR2:aTc + tetO1 ↔ tetR2:tetO1:aTc1E+081
tetR2:aTc2 + tetO1 ↔ tetR2:tetO1:aTc21E+081E+05
tetR2:tetO1 + aTc ↔ tetR2:tetO1:aTc1E+081E-03
tetR2:tetO1:aTc + aTc ↔ tetR2:tetO1:aTc21E+081E-03
tetR2 -> Ø2.89E-04
tetR2:aTc -> aTc2.89E-04
tetR2:aTc2 -> 2 aTc2.89E-04
tetR2 + nsDNA ↔ tetR2:nsDNA10003.2409
tetR2:aTc + nsDNA ↔ tetR2:aTc:nsDNA10003.2409
tetR2:aTc:nsDNA -> aTc + nsDNA1.93E-04
tetR2:nsDNA -> nsDNA1.93E-04
Ø -> tetR21E-11
aTc_ext -> aTc3.3E-04
gfp_mRNA -> Ø1.16E-03
gfp -> Ø3.21E-05
RNAp + tetO1:tetR2 + lacP -> RNAp:lacP + tetR2311000
RNAp + tetO1:aTc:tetR2 + lacP -> RNAp:lacP + tetR2311000
RNAp + tetO1:aTc2:tetR2 + lacP -> RNAp:lacP + tetR2311000


Tnnatcvariesleaky3.jpgTnnexperiment.jpg

As you can see from the above graph, this model shows no response to aTc concentration. The gfp output is the same whether there are 0 or 260 molecules of aTc in the cell. Essentially this system is completely leaky, which is not what is needed. Also, the model still peaks and decreases, instead of plateauing.