Patent ID: 8158595

Claim:
An aptamer-regulated ribozyme, comprising: (a) a cis-acting hammerhead ribozyme comprising a catalytic core and stem I, stem II and stem III duplex regions extending therefrom, said stem I having a loop I single-stranded loop region opposite to said catalytic core, and said stem II having a loop II single-stranded loop region opposite to said catalytic core; (b) an information transmission domain (ITD) having a first end and a second end, which information transmission domain is directly coupled to said loop I or loop II through said first end; and (c) an aptamer coupled to said information transmission domain through said second end, said aptamer binds to a ligand, wherein said ITD is between the cis-acting hammerhead ribozyme and the aptamer, and comprises: (i) a general transmission region, (ii) a switching strand that hybridizes with the general transmission region in the absence of the ligand, and, (iii) a competing strand that hybridizes with the general transmission region in the presence of the ligand, wherein the switching strand and the competing strand compete to bind to the general transmission region through hybridization interactions, wherein binding of said ligand to said aptamer favors a conformation change in the aptamer, wherein said conformation change causes the ITD to favor the binding of the general transmission region to said competing strand via a strand-displacement mechanism; and, wherein hybridization between the general transmission region and the competing strand causes, via the interaction of said information transmission domain with one or more of said loop, said stem or said catalytic core, said ribozyme to undergo self-cleavage of a backbone phosphodiester bond at a rate dependent upon the presence or absence of said ligand.