Small Self-cleaving Ribozymes
- 1Howard Hughes Medical Institute and Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 8109-1024
- 2The Center for the Molecular Biology of RNA and The Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, California 95064
- Correspondence: aferre{at}fhcrc.org and wgscott{at}ucsc.edu
Summary
The hammerhead, hairpin, hepatitis delta virus (HDV), Varkud Satellite (VS), and glmS ribozymes catalyze sequence-specific intramolecular cleavage of RNA. They range between 50 and 150 nucleotides in length, and are known as the “small self-cleaving ribozymes.” Except for the glmS ribozyme that functions as a riboswitch in Gram-positive bacteria, they were originally discovered as domains of satellite RNAs. However, recent studies show that several of them are broadly distributed in genomes of organisms from many phyla. Each of these ribozymes has a unique overall architecture and active site organization. Crystal structures have revealed how RNA active sites can bind preferentially to the transition state of a reaction, whereas mechanistic studies have shown that nucleobases can efficiently perform general acid–base and electrostatic catalysis. This versatility explains the abundance of ribozymes in contemporary organisms and also supports a role for catalytic RNAs early in evolution.
- Copyright © 2010 Cold Spring Harbor Laboratory Press; all rights reserved
