Figure 2. Synthesis and execution of RNA CHA circuit Figure 2. Synthesis and execution of RNA CHA circuit. (a) LHRz and RHRz-mediated cotranscriptional RNA cleavage releases the internal circuit components H1, H2 and C1. Fifity nanograms of PCR-generated transcription templates for H1, H2 and C1 was transcribed in 50 µl of reactions by T7 RNA polymerase for 2 h at 42°C. Two microliters of the resulting transcripts was analyzed by electrophoresis on a 10% denaturing polyacrylamide gel. Single-stranded DNA oligonucleotides were used as size markers. (b) RNA hairpins undergo catalyzed assembly into RNA duplexes. Gel-purified RNA catalyst C1 and the hairpins H1 and H2 were combined as indicated and incubated in 1× TNaK buffer containing 20 U of RNaseOUT for 150 min at 42°C (lanes 1–4), 52°C (lanes 5–8) or 62°C (lanes 9–12). The reactions were then analyzed on a 10% native polyacrylamide gel. Fifteen nanograms of C1 RNA was included in lane 13 as a control. Single-stranded DNA oligonucleotides were used as size markers. From: Design and application of cotranscriptional non-enzymatic RNA circuits and signal transducers Nucleic Acids Res. 2014;42(7):e58. doi:10.1093/nar/gku074 Nucleic Acids Res | © The Author(s) 2014. Published by Oxford University Press.This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com 1