Functional gene discovery using hybrid ribozyme libraries

Hybrid ribozymes that couple the cleavage activity of hammerhead ribozymes with the unwinding activity of RNA helicases are powerful tools in the study of cell genetics and pharmaceutical drug development. They are useful for targeting a specific gene as well as screening functional genes to show phenotypic alterations. By randomizing the binding arms within the ribozymes, we can create a library of ribozymes that are capable of cleaving any mRNA. After introducing the library into cells and recovering the sequence information of ribozymes that alter the cell phenotype of interest, genes that are responsible for the specific phenotype can be identified. This chapter describes a method known as the gene-discovery system to identify novel functional genes related to a specific phenotype. Our gene-discovery system should be a powerful tool for post-genome research.