Template:Leanna newesttoggle

From 2010.igem.org

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Revision as of 03:24, 10 October 2010

MIT iGEM 2010

toggle by parts

toggle abstraction

the bacterial uv toggle

In the beginning, there was a UV Toggle (Collins, 2000).
The 2010 MIT iGEM team saw that it was good, and decided to implement the Collins toggle in E.coli to create cells with bistable phenotypes. The team planned for the toggle to control fluorescence and phage polymerization. At first there was a pattern of fluorescence induced by UV exposure -- the first image.

Then the team decided to make the signal amplify itself, and record a movie to see its propogation. And it was so.

But the team noticed a circle of cell death where the UV exposure had killed some of the cells in the lawn. They decided to make a pLPTa, a low power toggle that still provided bistability, but required less UV power to induce a toggle switch. By site-directed mutagenesis, the team changed the lambda repressor (cI) gene in the Collins pTSMa to a cI that is more sensitive to cleavage by Rec-A, the enzyme activated by UV light exposure.

Here we see cells controlled by the Low Power Toggle. The cells fluoresce red with UV induction, but at higher UV levels cell death can be seen in the green field.

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-But the team noticed a circle of cell death where the UV exposure had killed some of the cells in the lawn. They decided to make a pLPTa, a low power toggle that still provided bistability, but required less UV power to induce a toggle switch.
+But the team noticed a circle of cell death where the UV exposure had killed some of the cells in the lawn. They decided to make a pLPTa, a low power toggle that still provided bistability, but required less UV power to induce a toggle switch. By site-directed mutagenesis, the team changed the lambda repressor (cI) gene in the Collins pTSMa to a cI that is more sensitive to cleavage by Rec-A, the enzyme activated by UV light exposure.
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