Nanocircles
Nanocircles are small circular single-stranded DNA that can be transcribed by phage and bacterial RNA polymerases. These plasmid-like structures were originally developed by Eric T. Kool's lab. The new technology uses a method called rolling circle transcription (RCT) to encode hammerhead, hairpin and hepatitis delta ribozymes.
Rolling Circle Animation Click on Rolling Circles & Artificial Telomeres
Goals
- Synthesize efficient self-processing ribozymes
- Regulatation of genes using ribozymes
- Change ribozymes while retaining randomized domain to emphasize universality
- Interchange genes for utility
- Reinforce importance of secondary structure in cleaving properties
Experimental Design
Figure 1. Structrure of single-stranded DNA nanocircle composed of 63 nucleotides encoding a hammerhead ribozyme and 41 nucleotides of randomized sequences
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Figure 2. Schematic of artificial ribozymes using error prone reverse transcripase PCR
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Results
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Figure 3. Rolling circle transcription can produce much more RNA than can transcription of linear, unligated DNA. Ligation is essential for RCT because it allows for the nanocircles that are best able to produce the most RNA to amplify these selective advantages to subsequent generations.
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Applications of Ribozymes in Synthetic Systems - Danielle Jordan
