Ribozymes in the nucleolus
Rossi, J.J.
Science 285(5434): 1685
1999
ISSN/ISBN: 0036-8075 PMID: 10523186 Document Number: 501797
Scientists report in The Proceedings of the National Academy of Sciences that a family of small RNAs in the nucleolus (snoRNAs) can promptly transport ribozymes into this subcellular organelle. Ribozymes are RNA molecules that act as enzymes, cutting other RNAs at specific sites into smaller pieces, and they may be important therapeutic tools for repairing cellular RNAs transcribed from mutated genes or for destroying undesirable viral RNA transcripts in the cell. For their experiments, D. A. Samarsky and colleagues selected yeast because the requirements for transporting a specific snoRNA, called U3, are well understood in this organism. They appended a test ribozyme to the 5' end of U3 and inserted its RNA target sequence into the same site in a separate U3 construct. The snoRNA-ribozyme molecule, called a snorbozyme, and its U3-linked target were transported into the nucleolus, where the ribozyme cleaved its target RNA with almost total efficiency.