1. The Riboregulator Isaacs et al., Nature Biotechnology, 2004 Method of translational control of gene expression cis-repressive sequence (“lock”) upstream of a gene’s coding region forms a hairpin, sequestering the ribosome binding site trans-activating (“key”) mRNA strand binds and opens the hairpin thus allowing access to the RBS. Highly specific activation occurs. Very similar lock and key pair sequences do not exhibit crosstalk

2. Results with lock3/key3 StrainFluorescence no plasmids31 lock3RFP44 key3 + lock3RFP78 OnRFP6415 + key3 lock3-RFP

3. Improved locks and keys Distance from RBS Presence of hairpin Position of terminator Transcriptional fusion Position of promoter Degree of homology Length of spacer Frame of homology

4. New key architectures Increases effective key concentration Increases stability

5. This is where we’d have the best lock and key pair detailed with specific dimensions and good assay data (e.g., FACS, QPCR, OD/flourescense time couse, et cetera). And it’d be cool if we had multiple pairs built by then so we could show a table or some sort of graphic that shows orthogonality.