Team:Chiba/System 1/Result

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(Difference between revisions)
(T7/CI-OR1 hybrid promoter)
(Requirement of realizing genetic double click system)
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1. T7 RNAP pulse in response to 1st and 2nd input<br>
1. T7 RNAP pulse in response to 1st and 2nd input<br>
-
In response to 1st and 2nd input, T7 RNAP has to make pulse like expression.<br>
+
In response to 1st and 2nd input, T7 RNAP has to express as pulse.<br>
-
1-1. Lux/CI434 hybrid promoter has to be activated/repressed stringently.
+
To accomplish this, Lux/CI434 hybrid promoter should be activated or repressed stringently.<br>
 +
So, we checked this part (Data shown below)<br>
-
2. CI repression
+
2. CI repression<br>
CI needs to work as a repressor of T7/CI-OR1 hybrid promoter at 1st input and needs to
CI needs to work as a repressor of T7/CI-OR1 hybrid promoter at 1st input and needs to
have degradated before 2nd input not to work as a repressor at 2nd input.
have degradated before 2nd input not to work as a repressor at 2nd input.
-
2-1. CI has to remain undegradated until the time T7 RNAP pulse have disappeared.
+
To accomplish this, T7/CI-OR1 hybrid promoter should be activated or repressed stringently.<br>
 +
So, we checked this part (Data shown below)<br>
-
3. Setting the limited time
+
3. Setting the fixed time<br>
-
There is the limited time between 1st and 2nd input.
+
There is the fixed time between 1st and 2nd input.
 +
To accomplish this, CI has to re-express after washout. (Data not shown)
===<font size="5">T7/CI-OR1 hybrid promoter <Favorite Part></font>===
===<font size="5">T7/CI-OR1 hybrid promoter <Favorite Part></font>===

Revision as of 21:51, 27 October 2010




 

 

 








Contents

Requirement of realizing genetic double click system


1. T7 RNAP pulse in response to 1st and 2nd input
In response to 1st and 2nd input, T7 RNAP has to express as pulse.
To accomplish this, Lux/CI434 hybrid promoter should be activated or repressed stringently.
So, we checked this part (Data shown below)

2. CI repression
CI needs to work as a repressor of T7/CI-OR1 hybrid promoter at 1st input and needs to have degradated before 2nd input not to work as a repressor at 2nd input. To accomplish this, T7/CI-OR1 hybrid promoter should be activated or repressed stringently.
So, we checked this part (Data shown below)

3. Setting the fixed time
There is the fixed time between 1st and 2nd input. To accomplish this, CI has to re-express after washout. (Data not shown)

T7/CI-OR1 hybrid promoter <Favorite Part>


T7/CI-OR1 hybrid promoter <Favorite Part>


  • [http://partsregistry.org/wiki/index.php?title=Part:BBa_K396000 BBa_K396000]

T7/CI-OR1 hybrid promoter was designed to be activated by T7 RNA Polymerase and repressed by lambda CI protein. In sequence design, lambda CI operator site 1 (OR1, Part of BBa_R1051) was directly attached to the downstream of T7 promoter sequence (BBa_I719005). This characterization was implemented to validate the promoter function. In results, the activation and repression was actually observed.


Checking the parts


Fig. Checking the parts




Results and Conclusion


Under the situation of CI non-expressed , T7 RNAP causes GFP expression by activating T7/CI hybrid promoter (Fig.1). On the other hand, under the situation of CI expressed, T7 RNAP does not cause GFP expression (Fig.2). The reason of this is considered as following. Under the situation of CI expressed, even though T7 RNAP tries to activate T7/CI promoter, the promoter Is repressed by CI because the ability of CI repression is superior to the one of T7 activation for this promoter. So it is concluded that T7/CI hybrid promoter is to be activated by T7 RNA Polymerase and repressed by lambda CI protein, following the rules of CI repression > T7 activation.

Fig. B Results




Reference


Dubendorf, J.W. & Studier, F.W. Controlling basal expression in an inducible T7 expression system by blocking the target T7 promoter with lac repressor. Journal of Molecular Biology 219, 45-59 (1991).