Ribozymes and siRnas: from structure to preclinical applications

M Sioud1

  • 1Institute for Cancer Research, Department of Immunology, Molecular Medicine Group, The Norwegian Radium Hospital, Montebello, 0310 Oslo, Norway. mosioud@ulrik.uio.no

Summary

Nucleic acids like small interfering RNAs (siRNAs) can inhibit gene expression for research and therapeutics. Chemical modifications are crucial for their stability and efficacy as drugs, but must not impede their RNA interference (RNAi) function.

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The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
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