Figure 1.

Conditional guide RNA with a two-hairpin mediated strand displacement as an RNA processing joint. (A) The concept for introducing a computing element as a joint between trigger and target RNA. (B) Schematics of the two-hairpin mediated nucleic acid computation in programming CRISPR/Cas9 function. The sequence-related strands are depicted by the same colour, and different colours indicate independent sequences of RNA strands. RNA X is sequence-independent of gRNA-Y and gene Y. After the two-hairpin processing, RNA X can activate the self-inhibitory gRNA-Y (SI-gRNA-Y) to regulate the gene Y.