Difference between revisions of "Part:BBa K1132005"

Latest revision as of 14:32, 25 September 2013

R0 riboregulator switch with pTET and pLuxRCI

The R0 riboregulator sequence is designed based on the publication of Callura JM (http://www.ncbi.nlm.nih.gov/pubmed/22454498). The principle is to introduce short regulatory sequences that create RNA secondary structures to better control protein expression. The basic design is reported in the following scheme (red hexagonal boxes, terminators; green oval box, rbs; blue and red rectangles, riboregulator sequences; arrows, promoters). Promoters P1 and P2 are controlling the expression of a single gene X (not present in the biobrick). Two terminators are placed between P1 and P2.

Transcription occurring at P2 promoter stops at terminators placed after gene X. However, the red sequence can fold into a RNA secondary structure, blocking the RBS, preventing ribosome binding. The gene X immediately placed after the RBS is transcribed but not translated (no protein X).

The P1 promoter controls the expression of a small riboregulatory sequence capable of interacting with the one blocking RBS, but stronger in term of interaction. If transcription occurs at both sites P1 and P2, a small RNA is produced that destabilizes the loop created on the RBS and therefore releasing the riboregulator and enabling translation.

The part is released without any gene and can therefore be used to better control any protein expression. The P1 promoter is pTET (BBa_R0040) and the P2 promoter is pLuxR (BBA_R0065). pLuxR can be changed with Bam HI and Cla I restriction sites.

Sequence and Features