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Team:Tokyo-NoKoGen/Project
From 2013.igem.org
Abstract
-Fast cycle! Fast response!-
This year, we will create Twinkle.coli! Twinkle.coli blinks luminescence like a firefly. To construct it, we need a circuit that oscillates at a short cycle and a fast responsive system. To make oscillating circuit of a short cycle, we designed RNA based oscillator. Some genetic oscillator circuits have been already created and reported. In such common circuits, the oscillation is generated by the expression of inducer and repressor proteins, creating positive and negative feedbacks. As The problem with these oscillators is that because they use proteins to move the oscillation, it takes time for proteins to be transcribed to mRNA, which then needs to be translated to amino acid, and folded into protein, we have to shorten the cycle to make Twinkle coli. To accomplish it, avoid such problem, we chose RNA as a repressor.
The key point in our RNA oscillator is the use of RNA responsible self-cleavage ribozyme, which can control and be controlled by other RNA. To make a fast responsive system, we use the concept of RNA scaffold. When RNA is transcribed as an output from the oscillator, the already translated and existing luciferase and GFP in the cytoplasm bind the transcribed RNA, and BRET occurs which is a shift in luminescence.
