Expression of Functional Ribozymes in Bacteria

A trans-acting hammerhead ribozyme, designed to cleave mRNA from the human immunodeficiency virus-1 integrase gene, was expressed in Escherichia coli from a plasmid-borne gene. Expression of the ribozyme at the same time as expression of integrase led to the disappearance of integrase mRNA and prevention of integrase production. A comparable antisense RNA was much less effective. The elements of the ribozyme gene are described to facilitate construction of ribozymes directed at other targets. Procedures for modeling ribozyme secondary structure, testing ribozyme activity, and inserting ribozyme genes into expression vectors are discussed.